# "Nina", a Gauge 1, 0-4-0 live steamer.  Progress and updates



## xo18thfa (Feb 20, 2010)

This little steam loco project is a single cylinder oscillator, gear and chain driven, 0-4-0 in 7/8 = 1 foot scale. The engine is single acting with a 1/2" bore and 11/16 stroke. The transmission is by gear to an intermediate shaft and then ladder chain to the lead axle. Total gear reduction is 4.8 to 1. That should provide some power as well as speed. The boiler is a single flue, gas fired T boiler. The vertical leg of the boiler should provide a lot of water and steam space while the horizontal leg provides room for a larger than normal flue.

This one is called Nina.

The primary inspiration for the Nina project is Mr Earnest Glasers Cracker. This is Mr Glasers original Cracker.







Here is a link to Mr Glasers plan set for Cracker.

http://home.iae.nl/users/summer/16mmngm/Articles_htms/Cracker.htm

Cracker is a Gauge 0 engine in metric dimension. For this project I plan to use the motor unit with a scale of 1mm = 1/16 to make it larger.

The chassis comes from Idris, designed and built by Mr Dave Watkins. 






Mr Watkins original Idris is in 16mm = 1 foot scale. I scaled up the chassis by a factor of 1.4 to get it to 7/8 scale. The Idris chassis will give Nina a longer wheel-base then Cracker and more room for the boiler. Dave has a plan set for Idris and his other engine at his website

http://www.davewatkins.pwp.blueyonder.co.uk/steam.htm

The rest of it will get made-up as we go along.

First parts to make are the main frames. They are from 16 gauge (.0598) cold roll, bright finished, steel plate. Here is the frame drawing:

http://1stclass.mylargescale.com/xo18thfa/Nina%2001/frame%20drawing.jpg

To start, saw out two rectangles, slightly over sized. 16-gauge plate is easy to cut. Clamp the sheet over the edge of the workbench with a piece of wood strip on top to keep it from chattering. Use a new blade in the hacksaw with a good shot of oil. Dont push down too hard, let the blade do the cutting.  

Finish the frame blanks so the edges are flat, sharp and square all around. First, paint a line of blue Dykem layout fluid on one long edge. With a straight edge, scribe a line close to the rough-cut edge:






Use a bench grinder to off-hand grind the sawed edge, close to the line. 






Your eye is very precise for this kind of work. You will get within .002 to .003 of the line with the grinder. If the grinder starts to chatter, its because the wheel is getting clogged with steel bits. Use a dresser to clean the edge of the wheel. Dont let the steel get hot. If the Dykem blue gets hot, the line goes away. 

After grinding, polish the frame edge with a technique called draw filing. Clamp the frame between slabs of wood in the vise. Squirt oil on a clean sharp file and hold it by both ends. Gently rub the file forward and back. Heres my son Andy doing the draw filing. Hes standing to the left, just out of the picture.






Work the entire length of the edge to remove the grinder marks. Draw filing removes metal fast, so dont push too hard. Little curly hairs of metal come off the edge like butter. The file teeth will clog up, so clean the file frequently.

Check your progress with a straight edge, holding it to the light. When you see a thin even line of light, the frame edge is flat.






After draw filing, the frame edge is polished bright and razor sharp. Use a fine file to take the sharp edges off.

Use a square mark off one end. Just as before, grind and draw file the end. Use the square to check progress.






Grind and draw file the remaining edges. This takes a little more time because you have cut the frames to final length and width as you make sure the edges are flat and square.

Clean up the frame blanks. Paint one side of one frame blank with Dykem blue. Measure and layout all hole centers and the curved out areas on the bottom edge.

From this point one we will work on both frames simultaneously. In the area the eventually gets wasted out on the bottom edge, drill holes for some #4 x 40 machine screws. Bolt the two frame blanks together.






The photo above does not show all the scribed lines in the Dykem blue showing all the hole centers. They are all in there, however. Lightly center pop all the hole centers. 

Admittedly, four-squaring stock is not much fun, but its essential. Next time we will drill and shape the frames in prep for assembly.


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## 4156df (Feb 20, 2010)

Bob,
I'm looking forward to following along as you build this. Thanks for posting. Keep the photos coming, please.
Dennis


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## vlmarshall (Feb 21, 2010)

Nice step-by-step thread. :bow: My Crackers are using a few Idris components, as well.


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## ozzie46 (Feb 21, 2010)

As Vernon said, nice write up. Will be following this one too.

  Ron


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## zeeprogrammer (Feb 21, 2010)

Great post Bob.
I very much appreciate the tips and techniques.


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## Seanol (Feb 21, 2010)

Bob,
 You say here: "Cracker is a Gauge 0 engine in metric dimension. For this project I plan to use the motor unit with a scale of 1mm = 1/16 to make it larger."

How big a track will you need? 

Will it be a stock scale? or guage?

Will you just keep the width for the track you use?

Any source of common track widths against guage size?

I am really new at this and I have 2 crackers in the works for my 2 children. I am interested in building a third scaled up but I would like to run all of them on a track at some time.

Thanks,
Sean


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## xo18thfa (Feb 21, 2010)

Thanks for all the kind words. This engine is about 1/3 of the way along. Got the transmission parts in yesterday and she's rolling smooth.

Sean: Gauge 0 track is 32mm or 1.25" between the rails inside measure. It is a standard track, and very popular. In The U.S. we call it "O" gauge, 1;48 scale, 1/4" = 1 foot. If you Cracker is to Mr Glaser's plan, it will run on "O" gauge track just fine. 

Gauge 1 track is 45mm or 1.75" between the rails and is track used in the outdoor, garden railroad hobby. Nina is for Gauge 1 track. 

In the garden railroad hobby, model railroaders use the same standard Gauge 1 track and vary the scale of the engines and cars. Some models may represent standard mainline equipment, some narrow gauge and some even industrial gauge. 

Since Cracker is Gauge 0 and I run on Gauge 1, it needs to be bigger. Setting a scale of 1mm = 1/16" increases the size of the motor so it is almost proportional to Gauge 1. Plus, it becomes inch measurement rather then metric.

Thanks again. Bob


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## Seanol (Feb 21, 2010)

Bob,
Thanks for that.

I just started scaling up the Cracker using this method. Much easier than trying to make mm into in!

Do you know of any garden railways or groups in town?

Thanks,
Sean


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## GailInNM (Feb 21, 2010)

About all you have to do to get a Cracker that is scaled a 1/16 inch = 1mm to run on Gauge 1 track is to move the scaled wheels in about 3/32 inch on each side to get 40mm true distance for the back to back distance between the wheels. If you do everything else at your proposed scale, a short spacer between the frame and the wheel set will do the trick. You might have to move the gears in a little bit, but probably there is enough clearance.

I have seen several Crackers and its derivatives done in similar manner.

There used to be (5 years ago) quite an active group of live steamers in the LV area, but I have not keep up with who is where these days.

Gail in NM


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## xo18thfa (Feb 21, 2010)

Yes, we have a Gauge 1 live steam group in Vegas. Meet 1st Saturday of every month. I sent you a PM Sean with the point of contact.

Also have a Garden Railroad club, good sized club. They are all "sparkies" (electric), but they let us oil up the club track with live steam mess once in a while.


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## Seanol (Feb 21, 2010)

Gail,
Thanks for the info. I am going to try to scale the entire loco up to see what happens. I will be building 2 more to the original scale for the kids as well.

Bob,
Replied to your PM and I look forward to meeting you one of these days, hopefully at an event near by!

Thanks for your help,

Sean


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## xo18thfa (Feb 21, 2010)

GailInNM  said:
			
		

> About all you have to do to get a Cracker that is scaled a 1/16 inch = 1mm to run on Gauge 1 track is to move the scaled wheels in about 3/32 inch on each side to get 40mm true distance for the back to back distance between the wheels. If you do everything else at your proposed scale, a short spacer between the frame and the wheel set will do the trick. You might have to move the gears in a little bit, but probably there is enough clearance.
> 
> I have seen several Crackers and its derivatives done in similar manner.
> 
> ...



That's exactly what I was going to do. In fact, that's how it started. Change of plan to use an Idris chassis for a longer wheelbase.


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## Seanol (Feb 21, 2010)

Gail and Bob,

Just so I know (and can stop hijacking the thread : ) 40 mm from back to back of wheels would be 1.5748 in. Right?

I had the spacing at 1.625 with 1/16th space on the outside of the wheels to the frame. This is placing the wheels inside the frame. I guess I thought that 1.75 in was inside distance between tracks.

I also have a reference showing 1 17/32 or 1.53125 in.

How close does it have to be?

Thanks,
Sean


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## shred (Feb 21, 2010)

In theory, Crackers built to plan can be re-gauged by merely moving the wheels from inside the frames to outside the frames. You have to use 1/16" or so material for the frames however. The relative scale will of course be different. It's sort of a 16mm narrow-gauge as-built.

Anyway, looking forward to progress on Nina.


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## xo18thfa (Feb 21, 2010)

Seanol  said:
			
		

> Gail and Bob,
> 
> Just so I know (and can stop hijacking the thread : ) 40 mm from back to back of wheels would be 1.5748 in. Right?
> 
> ...



That's right, 40mm or 1.575" back-to-back on the wheels for Gauge 1. If you get too wide the wheels could climb out of a switch as you go thru. Too narrow and you could drop between the rails on a bad section of track. 

Another thing is that Mr Glasers' dimensions for the wheel flange thickness and height are correct as they are. Don't scale them. Covert metric to inch and use what he specifies.

He shows a flange thickness on the wheel of 1.5mm or .059". That is right on for Gauge 1 too. The flange depth he shows is 2mm or.079 which is also right on.

There is a garden railroad club in the U.K. called "Gauge 1 Model Railway Association" (G1MRA) They established a club standard for wheels and gauge about 40 years ago. It has since become a very widely accepted standard.


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## GailInNM (Feb 21, 2010)

Sean,
There is a lot of latitude in the wheel placement. The back-to-back distance is important if you ever run on any track that has switches or crossovers so the back side of the wheel does not catch the guard rail and cause problems. The taper on the wheel tread fairly well takes care of the rest as the wheel set will self align on the rail. I just mentioned the back-to-back because that is the way it is shown on the Cracker plans. Lots has been written on it, but most any thing close will work OK. 

Here is a drawing that shows the "standard" dimensions.
http://www.nmia.com/~vrbass/steam/castwheel.htm

Ignore the "IF" dimensions. It is for fine scale models and is not the best for running.

Just noticed posts by Shred and xo18thfa while I was writing: There posts are probably more helpful than mine. All are correct.

Gail in NM


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## Seanol (Feb 21, 2010)

Gail,
Thanks for the link. Exactly what I was looking for!

I guess there are 2 things to look at:

Resetting the wheels on the as drawn cracker to the outside for Gauge 1 or scaling up 1/16 for every mm.

I am going to try scaling up first and make the as drawn loco's second.

Thanks,

Sean


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## Maryak (Feb 22, 2010)

Hi Guys,

Back in the days of steam and still today at a State level Oz is plagued by 3 gauges of railways.

Queensland 3' 6"
New South Wales 4' 8 1/2"
Victoria 5' 3"
South Australia - All of the Above
Western Australia - 3' 6" and another for Hammersley Iron.

OK what am I getting at - This; in SA there was a bogey exchange system in operation before a national standard gauge line was built so in full size practice the rolling stock was fitted with a new set of wheels to travel over the next leg of its' journey. It seems to me that, within reason, where there are only minor differences between sizes such as mentioned in this thread, the engines could all be of one size per class with the wheels adjusted to suit the final track size.

If I have aptly demonstrated my complete ignorance of model railways, I'm sorry.

Best Regards
Bob


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## xo18thfa (Feb 22, 2010)

Ive been thinking about this build for a long time. Cracker and Idris are both great little machines. Dave Watkins also has a nice looking Bagnall named Frog on his website. I would like to do that too someday.

For more on the Cracker check out the fan club at:

http://groups.yahoo.com/group/Steammodelloco16mm/

I really like this shot. It just looks like King of the Road.






It is time to drill all the frame holes. Since the frames are clamped together, the drilled holes will end up identical in both frames. 

I drilled all the holes on the milling machine table, but a regular drill press will work too. Clamp the frames to the machine table with a piece of MDF board or clean plywood underneath. The MDF board provides good backing under the frames. Use a steel bar to distribute clamping pressure. A center point in the drill chuck helps locate the hole directly in line with the spindle.






Use a magnifying glass to ensure the center point and hole center is lined up. Your eye is very precise for this work too. Use a center drill first to start the hole. Dont rely on the drill bit alone, is may wander off center.

The larger holes for the bearing are a bit scary to drill. Set the drill to the lowest speed. Use clamps on both sides of the hole. 






Use plenty of oil on the bigger bit. Feed the drill at a steady slow pace. You will feel the cut and get a nice curly chip.

With all the holes drilled, insert #4 x 40 machine screws in each hole and remove the screws in the wasted area.






Now it is time to cut out the curved areas on the bottom edge of the frame. Do this with a technique called chain drilling. Chain drilling basically creates a perforation to remove the bulk of the material. 






Evenly space a series of center punches. Drill them thru with a small bit. Drill each hole again with a slightly larger bit. Repeat until the holes are just touching each other. Saw thru the holes with a fine coping saw and remove the waste material.

Using the bench grinder and files, clean up the cut out area. As a final step, wrap a piece of 220 or 320 grit wet/dry sand paper on a rod and put it in the drill chuck. Oil up the paper and use it to clean up the scratch marks on the cut out areas.






Disassemble the frames. Clean off sharp edges with a fine file and deburr the holes. Rub the frames down with lacquer thinner or some other solvent to remove the Dykem blue. If the Frame Gods smile upon you, they will be identical and look great.






Thats it for now. Next time we will do the spreaders and get the frame assembled.


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## zeeprogrammer (Feb 22, 2010)

Nice looking frames Bob. Nicely detailed post too.

I always struggle with scale...a coin or something (quiet you guys) would be helpful.


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## xo18thfa (Feb 23, 2010)

Now its time to do the frame spreaders and get the frame bolted together. Many Gauge 1 engines use square bar stock for the spreaders. The spreaders not only set the frame plates, but also secure the end beams and foot plates.  Heres a drawing of the spreaders. 

http://1stclass.mylargescale.com/xo18thfa/Nina%2001/Spreader.jpg

The spreaders need centered holes tapped on each end. To tap those holes we first need a split collet to secure the square stock in the lathe chuck. This is the split collet.







The split collet is a 3/4" length of 1/2" round steel bar with an 11/32 hole drilled thru. With a hacksaw, split lengthwise thru the tube.

11/32 is the diagonal measure of a 1/4" square bar. Cut slightly over sized length of 1/4" square bar. Slip one into the split collet. It should fit just fine






Chuck the assembly in the 3 jaw, self-centering chuck. The split collet centers the square stock perfectly. Face off the end of the spreader blank.






The spreaders require tapped holes, centered on the ends. Tap the holes while the square spreader stock is still in the lathe chuck. A special tap holding tool is needed to do this.






The special tap holder is essentially a drill chuck attached to a short piece of rod. I made this tap holder about 30 years ago from a chuck I got at Sears. 

First center drill and drill a pilot hole for a #4 x 40 machine screw. Drill the pilot hole 3/8 deep. Chuck a #4 x 40 machine screw tap into the tool and insert it into the tail stock chuck on the lathe.






The tap holder and lathe tail stock ensure the tap is aligned and going squarely into the pilot hole. Grip the lathe chuck with your left and the tap holder with the right. With a drop of oil on the tap, turn the tap holder about 1/3 turn. Turn it back about half a turn to free chips from the tap.






It takes a little practice to do this process. The first hole you tap will probably take about an hour. Then a minute thereafter. 

Reverse the spreader blank in the split collet and face it to the final length. Drill and tap as before.

The spreaders need several more tapped holes depending on their location. The top front/rear spreaders secure the end beans and the foot plate. The bottom spreader, just the end beam. To tap these holes, use the drill press with cross slide table to both drill the pilot hole and operate the tap holder. Here is the set-up.






With the spreaders all done, assemble the frame.











Next time we will make and install the bearings.


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## Deanofid (Feb 24, 2010)

It's looking really good, Bob.

Dean


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## ozzie46 (Feb 24, 2010)

Nice pics and write up Bob. Oh and the frame looks good too. ;D ;D

 Ron


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## xo18thfa (Feb 25, 2010)

Thanks for kind words fellas.

Next up are the bearings. There are eight bearings total in three sizes. Four are for the axles, 3 for the counter shaft and engine and one engine main bearing. Ordinary bearing bronze is the material to use. Alloy #932, also called SAE 660, is the stuff. Here are the drawings

http://1stclass.mylargescale.com/xo18thfa/Nina%2001/Bearings.jpg

http://1stclass.mylargescale.com/xo18thfa/Nina%2001/Engine%20Bearing.jpg

The bearings are a straight turning job. It is easier to use a square tipped parting tool to turn the bearing shoulder and then part it off from the main stock. Chuck a piece of 1/2" bronze in the 3-jaw chuck. Center drill, drill and ream the bearing bore. Use the squared parting tool to turn the bearing shoulder.






Use the parting tool in the same set-up to part off the bearing.






The bearings go into the frame with soft solder. 50-50 lead/tin solid wire is the best. Its soft and shapes for the job at hand, so you get the amount you need, where you need it.

Clean the frame assembly and bearings in soapy water and dry. Cut some lengths of 1/4" and 3/16 stainless steel rod. These rods will eventually become shafts and axles, but for now they will help get the bearings in place.

Apply solder flux to the frame and bearings. Slip the bearings into the frame and use the shafts to align them. When you are ready to solder it will look something like this:






Smash some solder into a thin sheet with a hammer and cut it into long strips. To solder the bearings in use a regular Bernz-o-matic torch. Use a very small flame, the inner bright blue cone about 3/8 long. Heat slowly from the outside of the frame. When the flux starts to bubble, rub in the solder on the inside of the frame, against the bearing shoulder. The heat will eventually transfer thru and melt the solder. Add just enough solder to get a nice fillet. Let it cool down a bit and move on to the next bearing. When you are done, clean up in soapy water. The rods will hold the bearings in alignment as you solder. They will turn smooth and freely.

Bearings are in place.






Thats it for now. Next time we will work on some transmission parts and fix a major disaster.


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## 4156df (Feb 25, 2010)

Looking good, Bob. I've never had good luck with soft solder and steel. Clearly you've got it figured out though. Is that some kind of special flux you're using and did you do any prep other than the soap and water?
Dennis


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## zeeprogrammer (Feb 25, 2010)

Newbie question...is there a special reason why the bearings were soldered in? Could they have been press fit? Asking cause I'm working on a smaller loco myself.


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## ozzie46 (Feb 25, 2010)

Zee, I would guess the frames are not thick enough to hold pressed in bushes. They would work loose.

 Just my 2 cents.

 Ron


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## xo18thfa (Feb 25, 2010)

Dennis: I use a petroleum based brown paste flux. This particular flux is "Dutch Boy" brand from Lowe's plumbing dept. Flux can burn and ruin a solder job, so heat slowly. I just use dish soap and a tooth brush to clean everything. Rinse well and dry with a clean paper towel.

Zee: Soldering in the bearings with a shaft in place ensures perfect alignment. The shafts spin so freely. I am not skillful enough to press something like that and get it aligned.


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## zeeprogrammer (Feb 25, 2010)

xo18thfa  said:
			
		

> Soldering in the bearings with a shaft in place ensures perfect alignment. The shafts spin so freely. I am not skillful enough to press something like that and get it aligned.



Ah! Nice tip for me. I'm supposed to press fit. Lacking enough experience I wouldn't have thought about the alignment issue. Thanks for that. I'll be more careful.


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## xo18thfa (Feb 27, 2010)

Lets turn to the transmission components. Engine power is transmitted by gears to the counter shaft, then by ladder chain drive to the front axle. The total gear reduction is 4.8:1 The gears came from Stock Drive Products 

http://www.sdp-si.com/index.asp

The gear stock numbers I used are:

	Pinion (14 tooth):		A 1B11-N32014	
	Gear (30 tooth):		A 1B11-N32030

These are hubless brass gears. I do not know what possessed me to get hubless gears, because you need the hubs and set screws. So I had to add hubs. First turn some hub blanks that fit closely to the gears:






Silver solder the hub to the gear.






Chuck the gears in the lathe, drill and ream to match their shafts. Tap the hub for a #6 x 32 set screw.

The bottom line to this little mess is to get gears with hubs and set screws.

I was eager to see how the gears worked, so I assembled the shafts with gears into the bearings. The gears were in so tight they would just barely turn. Way too tight to try to run-in. In fact, you may as well just say they would not turn at all. What a disaster. 

The fix, fortunately, is not that hard. It involves some new lower bearings for the countershaft and some brain surgery.

The new bearings are eccentric, rather than all turned in line. The inner bearing bore is off-centered from the outer diameter by about .020 To make an eccentric bearing, chuck some 1/2" bronze in the 3 jaw chuck with some folded paper packing under one jaw. Drill and ream to 3/16.






Remove the paper packing and re-tighten the chuck. Turn the outside of the new bearing as you did before and part off.






It is a little hard to see in this photo, but the bearing bore is off centered from the outside diameter. The bore is slightly lower then center.






Now remove the lower counter shaft bearings from the frame. Put the axles and engine shaft back in their bearings. Heat the countershaft bearings until the solder melts. Gently tap them out.






Clean off excess solder blobs with a jack knife and get ready to solder in the new bearings. Flux up the new bearings and get them in place. Rotate the new bearings so the off centered hole is all the way down. This gives more distance between the shafts. Solder the new bearings in just as you did before.

The fix worked fine. The gears went in just right and turn free and smooth. The old bearings off to the scrap bin.






Disasters like this happen all the time. When they do, stop and take a break. Think thru the problem and come up with a fix. If you understand what the problem is, the fix will work.

Next time we will turn the wheels and see if the chassis rolls.


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## zeeprogrammer (Feb 28, 2010)

Nice post! Very glad the fix worked.


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## xo18thfa (Mar 1, 2010)

The wheels for Nina are fixed to straight axles with set screws tapped into hubs.  The use of set screws to fix wheels is fairly common with 16mm = 1 foot scale narrow gauge engines in the U.K. Set screws allow for adjustment of the wheels to so the engine can operate on either Gauge 0 and Gauge 1 track. 

There are a number of ways to make wheels. The method I used is purely based on material I had on hand. 

Heres the drawing for the wheel blanks:

http://1stclass.mylargescale.com/xo18thfa/Nina%2001/Wheel%20Blanks.jpg

And for the rim detail:

http://1stclass.mylargescale.com/xo18thfa/Nina%2001/Wheel%20Detail.jpg

The wheel blanks are built up with separate hubs and wheel disks. Turn the hubs from lengths of 5/8 diameter round steel bar. The wheel disks are roughed out from 1/4" steel bar stock. You can use brass for both as an alternative. Or you can the whole blank from solid.






Carefully bore the wheel disks to fit the hubs. Dont try to drill the wheel disks. A 1/2" drill on a light lathe will probably chatter too much and leave a poor result.






Clean the parts and silver solder the hubs in the wheel disks. The bright ring around the hub shows good penetration of the solder.






The large hub on the backside of the wheel allows all critical machining steps on the wheels to happen with one set-up in the lathe chuck.  Grip the wheel blank by the backside hub in the 3 jaw chuck. Turn a step into the wheel which produces the final tread diameter and flange thickness. Use a rather pointed HHS tool with a slightly rounded nose.






Rotate the compound slide on the lathe to 10 degrees and turn the front side of the flange. Skim very light cuts until the lathe tool just fits into the root radius between the wheel tread and flange.






Rotate the compound slide to 3 degrees and turn the tread on the wheel. Take light cuts, about .001 or .002 until the nose of the tool fits back in the root radius. Use a hand file to put a small chamfer on the sharp corner of the tread.

Reset to compound slide to zero and turn a decorative recess on the front of the wheel.






Center drill the hub and drill through to 15/64. Use a ream with cutting oil to finish the hole out to 1/4".






Turn the wheel around and grip by the front side hub. Turn the flange to the final diameter. Taper cut the back side of the flange to 10 degrees, just as the front.






With the lathe running, round over the flange edge with a hand file and some oil.






Take the wheel to the drill press and drill and tap for a #6 x 32 set screw






Do the other 3 wheel blanks in the same manner.

Next time we will turn some axles, work more with the transmission and get the chassis rolling.


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## xo18thfa (Mar 4, 2010)

The axles are straight lengths of 1/4" stainless steel rod. Face them to an overall length of 3.187

The wheels are not quite ready to go in between the frames. The hubs on the front side are over length and require some trimming based on the final frame dimension. Measure the inside width of the wheel bearings. Based on a 40mm back-to-back measure on the wheels, the thickness of the wheels and about .01 side-to-side play, figure out how much of the front side hub needs to come off. Do the measurements and math a few times to ensure you have the correct answer. Cant put the metal back on once it comes off.

Put the chassis all together and give it a roll.






Lets put in the rest of the transmission parts. Engine power from the counter shaft goes to the front axle by ladder chain drive. The rear axle is chained to the front axle to complete the drive. The ladder chain parts also come from Stock Drive Products. The chain is size #19 with a .185 pitch. The sprocket on the countershaft is 7 tooth and the front axle sprocket and coupling sprockets are 14 tooth. The parts numbers are:

		7 tooth sprocket		A 6C 8-1907		(1 req.)
		14 tooth sprocket		A 6C 8-1914		(3 req.)
		ladder chain		A 6Y 8-9		(2 feet)

The 7-tooth sprocket is ready to install as is. The hubs on the 14 tooth sprockets are too long and need some trimming. Use another type of split collet to hold the sprocket in the 3-jaw chuck.






This split collet is narrow and grips the hub of the sprocket, protecting the teeth from the lathe chuck.






Grip the collet in the lathe chuck. Skim off enough material so that two of these sprockets will fit on the front axle.






The last little part we need before putting in the chain drive is a stop collar. The stop collar goes on the counter shaft to keep it from sliding side-to-side. The collar is just a 1/4" length of 1/2" diameter brass rod. Drill a 3/16 hole thru and tap for a #6 x 32 set screw.






Assemble the chain drive to the front axle, along with the gear drive. 






When that piece of the transmission works smoothly, put in the drive sprockets from the front axle to the back.






The whole transmission turned out good. It turns smoothly and with almost no effort. The single cylinder oscillator should turn this with no problem.

The rolling chassis is almost done. Next time we will work on the front and rear beams, foot plate and some do-dads.


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## xo18thfa (Mar 7, 2010)

Today we will get caught up on some leftovers to finish the rolling chassis. So far we have not had to make any real decisions on the appearance of the engine. The end beam arrangements and couplers need a decision right about now. 

First are the end beams. Here is the generic drawing. The final profile is up to you.

http://1stclass.mylargescale.com/xo18thfa/Nina%2001/End%20Beam.jpg

There are two end beams. Their fabrication is the same as the frames. Square up two blanks, clamp them together and drill the holes. I decided to add concave rounds to the lower corners using the chain drill method.






I am partial to the U.K. profile. So the front-end beam of Nina will have a single buffer. The rear coupler is link and pin to use with some existing rolling stock. Here are the parts.






U.K. style buffers are straight turning jobs. Here is the plan.

http://1stclass.mylargescale.com/xo18thfa/Nina%2001/Buffer.jpg

The buffer pad is best turned from a slightly longer piece of stock. Then cut off and finished. Grip the stock and turn the backside of the buffer pad:






Cut off the pad from the stock, grip by the shoulder and turn the front. The front gets a round over using a file.






The buffer box is square bar stock. You can either make a split collet as with the spreaders or just center the stock in the 4-jawed chuck.

The coupler came from Ozark Miniatures. It is their 7/8 link and pin coupler cast in white metal. The coupler has a single #4 x 40 machine screw cast in place. I worried that a single screw holding the coupler could loosen and cause the couple to turn. So I soft solder the coupler to the end beam. 






White metal soft solders just fine. Just use a very small flame and heat from the backside.






If you go with a U.K. style buffer on the front, polish that baby so its radio-active.






Next up is the foot plate. It is from 16-gauge CRS plate. 

http://1stclass.mylargescale.com/xo18thfa/Nina%2001/Footplate.jpg

By now, you are an expert at working 16 gauge CRS plate. The only thing different about doing the foot plate is to use the chassis as a pattern to accurately layout the side indents. Measure the screw holes from the spreaders, just make sure no little erros crept in and the foot plate lines up. 






Put everything together and have a look. Looking nice.






This is the end of a major phase. The rolling chassis is all done. Next time we will get started on the motor unit.


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## zeeprogrammer (Mar 7, 2010)

Great post.

How did you get the buffer so bright?

I saw the reference to OzarkMiniatures...and being from the Ozarks...I had to go look.
But they're based in Utah! What?


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## xo18thfa (Mar 8, 2010)

zeeprogrammer  said:
			
		

> Great post.
> 
> How did you get the buffer so bright?
> 
> ...



Shined it up on the lathe. Filed the surface round, then wet/dry sandpaper with oil to 400 grit. Last step was old fashioned "Brasso" on a paper towel. 

Ozark was sold a few years ago and the new owners are from SW Utah. They have done a great job with an already fine business.


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## xo18thfa (Mar 14, 2010)

The rolling chassis was a major phase in the build. Next is the motor unit. It will go much quicker than the chassis. The motor follows Mr. Glasers Cracker plan with a scale of 1mm = 1/16. The only difference is that Ninas main engine bearing is part of the frame rather that the engine standard.

The part to do is the engine standard. The standard is a brass fabrication, which includes the stand and the manifold. Here is the drawing

http://1stclass.mylargescale.com/xo18thfa/Nina%2001/Standard.jpg

Start by squaring up a rectangular brass block. Layout and drill all holes.






As an editorial comment, a small milling machine is essential in the hobby shop. Not that you will do a lot of milling, if any, but the graduated XY table is so helpful for drilling. As an alternative, use a compound sliding table on a drill press. Something like this:






Grizzly has three compound sliding tables. Check page 647 of their online catalog. It would be well worth the investment.

Next, profile the upper portion of the standard. Do this by either sawing/filing or turning on the lathe. Turning on the lathe will chatter a bit. Just take light cuts.






The plan for the standard calls for 3/16 thick brass. All I have is 1/4". In order to thin it down, soft solder on a temporary chucking spigot.






Chuck up the standard and face down to proper thickness






Now turn the manifold. The manifold is a one-inch length of 3/8 brass rod. Drill both ends 7/16 deep with a #2 drill and tap with 1/4" x 40 TPI






Taps and dies above about 3/16 diameter used in live steam construction tend to be the same threads per inch (TPI). Either 32 or 40 TPI. They are loosely referred to as Model Engineering (ME) taps and dies. ME is an old school U.K. practice that has stuck over the years. Many commercially available boiler and plumbing fittings are ME. 32 and 40 TPI taps and dies are available from industrial suppliers such as Travers Tool, MSC Industrial Supply and Victor Machinery Exchange. I use all 40 TPI.

Below 3/16 most builders use standard SAE machine screw thread. For Nina, most small threads are either #6 x 32, #4 x 40 or #2 x 56

Many builders also use metric thread. Instead of 1/4" x 40, you could use M6 x .5mm. When deciding which thread to use, check into commercial availability of boiler and plumbing fittings. Otherwise be ready to make all that stuff your self.

The next step on the standard is to notch the back to accept the manifold. Do this on the mill or with a round file.






The last step for the standard is to silver solder the manifold to the stand. After cleaning up, bolt the standard on the to frame.






Thats it for now. Next time we will continue the motor.


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## arnoldb (Mar 15, 2010)

Bob, that is really coming along well ! Thm:

Regards, Arnold


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## xo18thfa (Mar 17, 2010)

Thanks Arnold:

Today we are going to build up the lower rotating assembly for the motor. The flywheel and crank shaft, first the flywheel.

There are two options for the flywheel. One with a larger diameter and thinner rim and another smaller diameter and more stocky. Either will work or you can customize your own. Just make sure it fits the notch on the foot plate. Here are the two plans.

http://1stclass.mylargescale.com/xo18thfa/Nina%2001/Flywheel%20A.jpg

http://1stclass.mylargescale.com/xo18thfa/Nina%2001/Flywheel%20B.jpg

For an usual and professional touch, turn the flywheel from stainless steel. Highly polished stainless steel has karma. And while everyone elses stuff is rusting out, yours will still look cool. A lot of builders worry about stainless steel, that it is too hard to turn. Actually it is not that bad. Use a free machining alloy of stainless steel, such as #303 or #416. Turn stainless at a slower speed and use a lot of oil. The oil will smoke and stink-up the shop, but the result is worth the effort. High Speed Steel (HSS) tools will get dull. When you get to the last .005 or so, re-sharpen the tool and take the last cut with oil. Polish the rim with oiled sandpaper to a high luster.

An alternative to stainless is cast iron. Polished cast iron makes a statement too. Cast iron is easy to turn. Turn it dry at very low speed. 

Turn the front side of the flywheel from a longer section of stock. Drill and ream for the crank shaft. Turn a decorative recess as desired.






Cut off the flywheel from the stock. Chuck from the front side and turn the reverse. Chamfer the sharp edges with a file. Tap the hub with #6 x 32 for a set screw.






You will be very relieved when the flywheel is done. And sore. Sawing a 2 bar is no fun.

Next is the crankshaft. The crank is assembled from three parts using Loctite. Here is the plan:

http://1stclass.mylargescale.com/xo18thfa/Nina%2001/Crank%20Shaft.jpg

Cut a length of 3/16 stainless steel rod for the shaft. The plan says 4, but cut a little extra and trim to length based on the flywheel you use.

Turn the backside of the crank disc from a longer piece of stock. Drill and ream 3/16 somewhat deep for the shaft.






Clean the shaft and hole in the crank disc with solvent. Apply Loctite Compound #680 to the crank disc hole and the shaft. Insert the shaft into the disc. Use the lathe tailstock to align the shaft to the disc.






Leave it set for about 30 minutes, then clean of the excess Loctite with solvent. If the excess Loctite hardens, it is nearly impossible to remove. Leave the assembly sit in the lathe overnight to fully cure.

Cut off the crank disc from the main stock and machine it clean on the lathe. Drill the crank for a 1/8 wrist pin. Use Loctite to set the wrist pin. Crank is done.






Assemble the rotating parts. The flywheel will give quite a bit of momentum to the chassis. Rotate the crank by the wrist pin. It will be effortless.






Its looking very good. Next time is the cylinder.


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## 4156df (Mar 17, 2010)

Bob,
This is looking good. Super write-up.
Dennis


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## zeeprogrammer (Mar 17, 2010)

Very very nice.
I really appreciate all the tips throughout your posts.


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## 1hand (Mar 17, 2010)

I'm enjoying your build. I'm not very knowledgeable when it comes to trains, even though my bedroom was a mer 200 feet from the RR tracks when I was a kid. They have always fascinated me though.

1 question: Can someone explain to me how the Loco number system works or what it means? 0-4-0???

Keep up the great work!!
Matt


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## Maryak (Mar 17, 2010)

Matt,

My understanding. 

0-4-0 etc is a system for showing the wheel layout of a steam loco

0 no front bogey wheels, 4 driving wheels, (the powered wheels); and 0 no rear bogey wheels.

Hope this helps, and I also hope it's correct. :

Best Regards
Bob


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## xo18thfa (Mar 19, 2010)

Maryak  said:
			
		

> Matt,
> 
> My understanding.
> 
> ...



That's it. The first number is always represents an unpowered leading truck, or pilot. The last number represents an unpowered trailing. The numbers in the middle are the powered wheels. All numbers are even. Mine is 0-4-0, no unpowered pilots or trailers, just 4 powered wheels. 

To add to it, most steam locomotives have names associated with the wheel arrangement. For example a 4-6-2 is called a Pacific. It has a 4 wheeled pilot, 6 drivers and a 2 two trailing truck. A 2-6-0 is a Mogul.

Do a Google search on "steam engine wheel arrangements"


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## xo18thfa (Mar 21, 2010)

Its been a while since the last update. Reason for that is because I was having some trouble getting the cylinder done right. The original plan was to drill and ream the 1/2" bore in a bronze cylinder blank. Reaming that size turned out difficult for my little lathe. There was too much chatter and the resultant bore not very clean. I decided to abandon the ream and use a traditional boring bar instead.

In preparation for turning the cylinder, my old Atlas 6 lathe got an upgrade this past week. I ordered a quick-change tool post set from Littlemachineshop.com






A quick-change tool post allows you to set the tool in its holder just once and then quickly change the holder as needed. This post is much faster than the original rocker style post and light years ahead of those 4 position turret things that come with most lathes. 

Before getting started on the cylinder, we need to fabricate a special little measuring tool called a center test indicator. They are also known as a wiggler, or wobbler. The wiggler helps get an odd shaped piece centered in the 4 jawed chuck. Here is an article I found on how to make one. 

http://1stclass.mylargescale.com/xo18thfa/Nina%2001/Wobbler.jpg

Modify this idea to suit you lathe. And here is an illustration of how to use it.

http://1stclass.mylargescale.com/xo18thfa/Nina%2001/Wiggler.jpg

My homemade wiggler is a 2-piece contraption using a ball for the pivot point.






With that done, lets get started on the cylinder. Here is the drawing:

http://1stclass.mylargescale.com/xo18thfa/Nina%2001/Cylinder.jpg

The cylinder body is bronze, alloy 932. Bronze only comes in round bar and our cylinder is more or less rectangle. So we will have to start with an oversized bar and work it down. First, face off a length of 7/8 diameter bar to 1 3/8 long. Grip the bar sideways in the 4 jawed chuck and turn it flat to a width of 5/8






This face spot will eventually be the port face.

Locate and lightly center punch the cylinder bore center. Grip the cylinder in the 4 jawed chuck and center it up with the wiggler. 






Drill a 1/8 pilot hole thru the cylinder. With the lathe set at the slowest speed, preferably in backgear if your lathe has one, drill thru with 7/16.






Set up the boring bar in the lathe. Since there is 1/16 of material yet to remove from the bore, you have plenty of time to set-up, practice and make adjustments before taking the final cuts.






Take very light cuts. Even the most rigid boring bars find a way to spring. So take a cut occasionally without any adjustment.  Let the bar relax out. Test the bore with a short length of 1/2" stainless steel piston material. The piston material will eventually go in very tight. Dont force it. Take another super light cut, and test the piston again. When the piston just goes in, its time to stop the boring bar operation and finish the bore.

Be patient boring out he cylinder. Expect 18 to 20 passes with the boring bar to get it right.

High quality cylinder bores are finished with a process called lapping. Lapping uses a fine abrasive powder mixed in oil on a lapping mandrel to polish the bore. Since our cylinder is bronze, a hard wood mandrel will work fine. Turn a 4, or so length of maple or oak to exactly .500. Wipe on some abrasive powder mix. Slide the cylinder over the mandrel and turn it by hand. It will be tight at first, but the wood will smoothen down and the cylinder will turn freely.






When the cylinder is turning freely, hold it buy hand and turn on the lathe. Work the cylinder over the entire length of the mandrel. It will only take about 30 to 45 seconds for the lap to polish the bore. The bore comes out free of scratches and with a lightly frosted surface. The piston material should slide smoothly with no air blow-by.

In the lapping process, the mandrel must be a softer material the cylinder material. The abrasive lapping compound embeds itself in the softer mandrel and polishes the cylinder walls. For brass and bronze cylinders, wood mandrels work fine. For steel or cast iron cylinders, use a brass or copper mandrel. Lapping only removes micro scratches and burrs left from the boring bar. The initial bore has to be straight, round and reasonably smooth. If the bore is bad to start with, lapping will not fix it.

Thats it for now. Next time we will shape the cylinder, put on a top cover and hang it on the standard.


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## zeeprogrammer (Mar 21, 2010)

Great post! I am learning so much from this thread. Thanks!


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## xo18thfa (Mar 23, 2010)

Thanks Carl.

Last time we got the cylinder bore finished, today we will get the rest of the cylinder done. When the cylinder came off the lapping mandrel, it looked like this:






There is a lot of excess material to remove. Chuck the cylinder sideways in the 4 jawed chuck and face down the sides.






At this point start using strips of paper as packing to prevent the chuck jaws from marring finished surfaces.

With the sides faced down, draw file the rounded surface of the cylinder to get the mill marks cleaned off.






Set up the cylinder in the drill press vice to drill and tap for the 4 x 40 trunnion pin.






The cylinder block is essentially finished. The next parts are the cylinder top cover and trunnion pin. First the top cover. Heres the drawing:

http://1stclass.mylargescale.com/xo18thfa/Nina%2001/Top%20Cover.jpg

The top cover is brass and is soft soldered to the cylinder. Start by cutting a 1/4" length of 3/4" round bar. Soft solder on a chucking spigot, just like we did for the engine standard.






Chuck up the top cover and face down to clean metal. Dont worry about getting the cover centered in the chuck. We are just cleaning this face off. This faced surface is the top of the cover. 






Melt the chucking spigot off and re-solder it to the faced off side. Chuck it up in the lathe and turn the outside diameter to 5/8






Face the top cover to length and turn the should that fits inside the cylinder.






Melt off the chucking spigot. Use a file and sandpaper to clean of the excess solder.

Now soft solder the top cover to the cylinder. Use just a TT of solder to put the cover on. Dont run the risk of a solder blob running down the inside of the cylinder.






The last part for the cylinder is the trunnion pin. The trunnion is the pivot point of the oscillating cylinder. Heres the drawing:

http://1stclass.mylargescale.com/xo18thfa/Nina%2001/Trunnion%20Pin.jpg

The usual method to make this pin is to turn a shoulder on the bar stock and cutting the threads with a die. That is nearly impossible to do with threads this small. Instead make the pin with a length of stainless steel rod and two 4 x 40 machine screws.

Cut a 7/16 length of 5/32 stainless steel rod. Tap both ends for 4 x 40.






Use Loctite #242 to lock the machine screws into their holes. When the Loctite cures, trim the machine screws to length.






With the trunnion pin installed, the cylinder is pretty much done.






Next time we will drill the port holes and lap the faces. Maybe even get on the piston. The air test is right around the corner.


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## 4156df (Mar 24, 2010)

Bob,
Soldering a chucking spigot to a part is a tip I hadn't seen before. Neat idea. Thanks for posting it. The engine looks great.
Dennis


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## bearcar1 (Mar 24, 2010)

Great looking work Bob, I am surprised that you did not do an undercut of of the central portion of the sliding face in order to reduce the frictional area and that you did not drill the steam ports before the attachment of the pinion stud. Very cool looking engine it is so far and I am anxious to see it as it develops.

BC1
Jim


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## xo18thfa (Mar 24, 2010)

Dennis I don't remember where I first saw that trick. Back when castings were widely used in model engines, a spigot was cast in and then cut off after machining.

Jim: That may still happen. I would only take a few minutes to do. The stud is not permanently installed yet. But you are right, I should have drilled the port when it was set up.

The air test is soon. I am getting nervous.

Bob


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## xo18thfa (Mar 24, 2010)

We still have some work to do on the cylinder. One of the things to do is drill for the steam, exhaust and cylinder ports. According to Mr Glasers original Cracker design, the ports are 1mm. Using the scale of 1mm = 1/16 our ports should be 1/16. This just seems too small to me, so I am going to try 0.0785 (#47 drill) first and see how that works. If its too small, I will open them up some more. But for now, we will try that.

First drill the port in the cylinder. I should have done this last time when it was set-up for the trunnion pin. 






Now drill the ports in the engine standard for the steam and exhaust. The best way to do this is with a drilling jig. It would probably be impossible to lay these holes out any other way. Here is the jig plan:

http://1stclass.mylargescale.com/xo18thfa/Nina%2002/Port%20Jig.jpg

Here is the jig and a little spacer piece.






The jig simulates a rigid piston/cylinder. It puts the port holes in the right spot. Set up the jig with the engine standard and crankshaft.






Before trying to drill this, build up a cradle from a piece of plywood or MDF. Drill recesses to clear the bearings and screw heads and the engines firmly on the side frame.






Use the drill press to drill ports. Prop up the engine standard your thumb under the manifold to keep everything level. Drill deep enough to break into the manifold center. Reverse the jig to drill the other side.






The next step is to lap the port faces on the engine standard and cylinder. The port faces need to be perfectly flat and smooth. To lap the faces we need a surface plate. For hobby purposes a small slab of thick plate glass is flat and true enough. Go to a good glass shop and have them cut a piece of 3/8 or 1/2" thick plate glass to about 8 x 10 and round the edges. They will mostly likely have a scrap piece ready to go in the junk bin.






The lapping material is a sheet of good quality wet/dry sandpaper in about 320 grit. Wet the paper with water and lay it on the glass. The paper will lay done tight against the glass. Rub the port faces of the cylinder and engine standard on the paper in a circular motion.






Continue to work the port faces until all scratches are gone. The faces will have a slight frosted appearance. 






The frost is a good thing. My mentor taught me that the frost is microscopic scratches that help hold oil in place and lubricate the surfaces. Highly polished surfaces will squeegee the oil away and cause wear or binding. I have had that happen, I believe my mentor. 

Thats it for now. Next time is the piston. Maybe the air tests too. I am getting nervous.


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## Deanofid (Mar 24, 2010)

Things are coming along nicely, Bob. 
It's an interesting build.

Dean


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## xo18thfa (Mar 26, 2010)

Thanks Dean.

Today we are going to get this motor unit finished and Nina running on air. The piston is the last part to do. By now you have enough machining expertise that the piston is easy to knock out.

The piston is in 3 parts and just screws together. Start with the bottom end, known as the big end. The piston big end is a drilling and turning job from 1/4" square CRS. Here is the drawing.

http://1stclass.mylargescale.com/xo18thfa/Nina%2002/Piston%20Big%20End.jpg

Start by facing off the stock and drilling and reaming the 1/8 hole for the crankshaft wrist pin. 






We are going to do something different. We are going to completely machine the big end with just one set-up in the lathe. The finished part will be ready to install. Chuck the square stock in the 3 jawed chuck using that collet you made for the spreaders. Hope you did not throw it away. Drill and tap for the #4 x 40 piston rod.






Now turn a little shoulder.






Its time to try a new gadget that came with the quick-change tool post set. It is a parting tool. A parting tool is basically a knife tool that plunges into the stock to cut the finished part off. This particular parting blade is only 0.040 wide, which is about the thinnest available.






Run the parting tool at a somewhat lower speed then regular turning and use oil.

Next is the piston rod. Make it exactly as you did for the trunnion pin. Drill and tap both ends of a 5/8 length of 5/32 stainless steel rod. Loctite in some #4 x 40 machines screws and trim to length. Too easy, heres the drawing.

http://1stclass.mylargescale.com/xo18thfa/Nina%2002/Piston%20Rod.jpg

The piston is straightforward too. Chuck some 1/2" round stainless steel stock. Face, drill and tap for #4 x 40 to accept the piston rod. With the lathe running, polish the rod with #320 grit wet/dry sandpaper and oil. For an extra smooth surface, repeat with #440 grit. Cut off the polished piston and face to a length of 9/16. Here is the drawing

http://1stclass.mylargescale.com/xo18thfa/Nina%2002/Piston.jpg

Here are the piston parts ready to assemble.






Put it together with some Loctite #242 and its ready to go.






Time for the air test. Put the engine together including the drive train. Everything needs to run. Oil all the moving parts. Secure the chassis to the bench and attach an air source. Turn on the air, give the flywheel a spin and see what happens. 

And there it goes.






It started up, ran jerky for about 15 seconds, then smoothened out. I stopped it after about 2 minutes, disassembled and cleaned it. The oil was blackened a lot. I suppose it cleaned out the last of the gook. The engine ran about 2 hours, stopping every 15 or 20 minutes to clean and add oil. The speed was about 250 RPM.

Some observations:

- The spring used to retain the cylinder was way too light. It is 1/4" wide and 1/2" long, 0.015 diameter wire and about 8 turns. The slightest air pressure lifted the cylinder off the port face. After clamping down nearly all the way, it ran normally. I will need to order a slightly stiffer spring.

- The motor runs with a lot of power. I was surprised. If the torque-o-meter (finger on the wheels) is any measure, it was difficult to stall. 

- It took very little air to turn the drive rain. Seemed like just a trickle. I need to find a low pressure gauge and see what it is really running at.

- Almost no friction between the cylinder and port face. The oil seems to form a film so there is no real metal-to-metal contact. The piston is airtight and no friction.

- After 2 hours of running there are no signs of wear.


We are calling this air test a success.

Next time we will start on the boiler.


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## 4156df (Mar 26, 2010)

Bob,
You make it look easy. Can't wait to see this one on the tracks.
Dennis


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## Swarf Rat (Mar 26, 2010)

Bob, I think this is an impressive model, I've been following the thread and learning. Maybe one of these days I'll attempt something like this.


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## zeeprogrammer (Mar 26, 2010)

I 2nd what Dennis said...you do make it look easy.
Wow...it's really coming together.


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## Maryak (Mar 26, 2010)

Bob,

Looking very good, nice work. :bow:

Best Regards
Bob #?


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## xo18thfa (Apr 27, 2010)

All the spring clean up chores are done, so we are back on the Nina project.

The boiler is a single flue, gas fired, T shape. The T shape allows for large water capacity in the vertical barrel and extra heating surface on the flue in the horizontal barrel. The vertical barrel is from 2 1/2" nominal copper pipe. The horizontal barrel is from 1 1/2" copper pipe. The flue is a length of 3/4" copper coupling pipe. Coupling pipe is used for plumbing repairs and is larger in diameter then the nominal pipe. 3/4" couple pipe is almost 1 diameter.

The end plates and flue sheet are from 1/8 flat copper plate. In small, low-pressure boilers for Gauge 1, there is no need to flange the end plates. The plates just get turned on the lathe to fit their barrels.

Before getting started we have to make some decisions. Mr Glasers original Cracker design is very basic. His boiler has neither a throttle, nor a safety valve. His design is satisfactory that way. There is an unobstructed path from the boiler to the engine. The engine runs when boiler builds enough pressure. If there is too much pressure, the oscillating engine acts as a safety valve, just as we saw during the Nina air test. 

I want to put a throttle on Nina. With a throttle, we need a safety valve. We will do a lubricator, which Mr Glaser left off of the Cracker. I also want a site glass and a water fill plug. So basically, all the boiler fittings. 

Here are the drawings for the boiler:

http://1stclass.mylargescale.com/xo18thfa/Nina%20Boiler/Boiler%20D1.jpg
http://1stclass.mylargescale.com/xo18thfa/Nina%20Boiler/Boiler%20D2.jpg
http://1stclass.mylargescale.com/xo18thfa/Nina%20Boiler/Boiler%20D3.jpg
http://1stclass.mylargescale.com/xo18thfa/Nina%20Boiler/Boiler%20D4.jpg

Start off the boiler by cutting the barrel sections and flue slightly over length. Square the sections by clamping a block of wood at a right angle on the disk sander. Turn the barrel as you sand. It squares up in no time.






Next, drill the 3/8 holes in the vertical barrel for the site glass bushings. Securely clamp the barrel and set the drill to very slow speed. 






Rough saw the top and bottom boiler sheets from 1/8 copper plate and drill for their bushings. The top plate gets 3 bushings: throttle, safety valve and water fill. The bottom plate gets 2; both are blind mounting bushes.






The boilerplates get turned on the lathe to fit the vertical barrel. Use a square block of hard wood, oak or maple, as a sacrificial faceplate to turn the plates. Fix the plate blanks to the wooden faceplate with #8 sheet metal screws.






Use your center test indicator (wiggler) to center the plate in the lathe. Turn the plate down so it just fits inside the boiler barrel. Not too loose, not too tight, just right.






Run the lathe tool well into the wooden faceplate to ensure the cut is complete. Do the top and bottom plates the same way.

The front flue plate has 2 turning operations, a hole for the flue and the outside to fit the horizontal barrel. Drill 2 holes for #8 sheet metal screws in the center, wasted out area of the flue sheet. Mount the flue sheet to the faceplate and center in the lathe.






Turn the outside to fit the horizontal barrel. With the flue sheet still in the lathe, drive in 3 sheet metal screws around the perimeter.






Pull the center sheet metal screws out and turn the center of the flue sheet to accept the flue.






Here are the plates all cleaned up and ready to silver solder.






Thats enough for now. Next time we will work on the boiler barrels to get the outer shell fitted up.


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## xo18thfa (Apr 30, 2010)

Plenty of metal cutting and fabrication work to do on the boiler before silver soldering everything together. First up are the bushings. There are 2 boiler mounting bushings and 5 for the plumbing. When planning the boiler it is a good idea to add extra bushings for the plumbing even if you dont plan use them. For example, you may not want a sight glass on this boiler, but in the future you might. So add the sight glass bushings now and just cap them off. Another thing to consider is the boiler fittings you want to install. You can purchase commercially made fittings, if so, tap the bushings to suit. We will fabricate our own fittings for Nina.

The bushings turn up the same way as the wheel and countershaft bearings. Not much more to add, you are a pro at this by now. Here are the drawings.

http://1stclass.mylargescale.com/xo18thfa/Nina%20Boiler/Bush%201.jpg
http://1stclass.mylargescale.com/xo18thfa/Nina%20Boiler/Bush%202.jpg

The next task is to cut 2 large holes in the vertical barrel to accept the horizontal barrel in the front and the flue in the back. The usual way would be to rough cut the holes, then finish with files. Instead of that, we are going to set up the lathe to bore these holes out. First, chain drill and saw out the hole.






Now take the compound slide off the lathe and see whats under that we can use to mount a barrel holding fixture.






Fabricate a fixture from hardwood to secure the boiler barrel to the lathe carriage. Years ago I tapped a 5/16 x 24 hole in the cross slide so I could screw in a long bolt if I ever needed too. Some of the import lathes have T slot tables for cross slide. Those would be ideal for this job.






Secure the boiler barrel to the fixture and align so the center access of the lathe passes thru the centerline of the barrel.






Chuck up a little home made fly cutter in the 4 jawed chuck. This hurry up fly cutter has a small set screw to hold a short length of lathe tool ground for this particular job.






Set the lathe to run at a slow speed and engage the carriage. Take light cuts by making small adjustments to the fly cutter in the 4 jawed chuck.






A real machine shop would have a special attachment called a boring head for this task. A boring head can be set to take a very precise, known cut. Our fly cutter is not as precise, but does the job very well. Very small adjustments to the chuck make for even smaller cuts. It took a lot of passes and time, but the result was right on.






Turn the barrel around in the fixture and machine the hole for the flue in the same manner. All the copper parts are cut out and almost ready for soldering






Sorry, there is one more thing to do. Re-cycle the fixture to machine a hole in the horizontal barrel to accept the smokestack






You can certainly cut these big holes by chain drilling and filing. But part of the whole process is to find different ways to use our limited shop equipment to do complex tasks. Now we know how to set-up a lathe as a horizontal boring machine.

Next time we will do some little house keeping tasks and get ready to solder this thing together.


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## 4156df (Apr 30, 2010)

Bob,
Nicely done. Very creative. I like your approach of getting the job done with what you have.
Dennis


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## kvom (May 1, 2010)

Nice build, just got caught up.

I'm decoding your forum name as executive officer of the 18th field artillery. Right?


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## xo18thfa (May 5, 2010)

There are 2 little tasks we need to pick up before soldering the boiler. The first is to solve a problem I know is going to happen with the top and bottom plates. The plates fit just fine, but will become unstable as the torch warms the boiler and will fall out of place. I know it will happen. To solve that, drill 3 small holes around the edge of the vertical barrel and drive in some copper pins. The pins will act as a shelf for the plate to rest on during soldering. This is what we want:







The second thing is to make a fixture jig to help install the site glass bushings. The site glass bushings must be flat to each other or the site glass will not line up correctly. Here are the parts for the jig and the bushings.






Assemble the jig with the bushings. The bushings are flat against the jig and will line up as we need them.






Put the assembly in the vertical barrel. These bushings are ready for solder.






There are a number of silver soldering techniques and methods. They all work as long as the resultant boiler passes all its tests and operates the engine in a safe manner. The best method is the one you grow up with or are the most comfortable with. The techniques I use comes from Kozo Hiraoka and his construction of 3.5 gauge live steam geared locomotives. Wolverine Joining Technologies has some very good online instructional documents at their website (www.silvaloy.com/home.php)

The solder is a medium-low temperature alloy consisting of 45% silver, 15% copper, 16% zinc and 24% cadmium. The common trade names are: Easy-flo 45, Silvaloy 45 or Safety-silv 45. It has a melting temperature of 1125F and flows almost immediately. As a word of caution, cadmium is poisonous. It vaporizes during the soldering process. Do your silver soldering outdoors or in a well-ventilated shop.

Silver solder requires a flux to chemically clean the metal as it heats. The flux is a white, water-based paste specifically matched to the solder. There is also a black colored flux used for stainless steel. The white flux is intended for non-ferrous and regular steel. All manufacturers and suppliers of silver solder have the flux as well.

I believe the 2 most important things in good silver soldering are the torch and understanding the flux. The torch must produce a large volume flame of low temperature. The solder melts at only 1125F, so there is not much need for higher heat. A propane-air torch with interchangeable tips is commonly used. This is the torch I use:






This torch comes from Sievert. It consists of a regulator that connects to the tank, 10-foot hose, a valve handle, neck tube and interchangeable tips. The gas tank is a standard, refillable 5-gallon bar-b-que tank. The tips I have are the #2942, #2943 and #2944. The #2942 is the small tip on the bench. It has a max output of 26Kw or 89,000 BTU. The #2943 is on the torch. This tip did all the work on the Nina boiler running at about 2/3 throttle max. It has a max output of 44Kw or 148,000 BTU. The big #2944 is a real volcano. I only fired it once and it scared the snot out of me. Its max output is 86Kw or 300,000 BTU.

The second critical thing after the torch is reading the stages the flux goes thru during soldering. Out of the jar the flux looks like toothpaste. As it first heats, the water boils off and leaves a white cake. The top of the white cake turns brown as it begins to melt. The flux continues to melt and turn brown. As the heat increases the flux starts to bubble and turn more transparent. Each time a bubble pops you see very bright shiny metal underneath. The flux reaches its final stage when it is almost completely clear. At that point, just a pinch more heat, the solder melts and runs like crazy. The flux has a maximum temperature of 1400F. After that it chemically breaks down and is useless. No amount of heat will make the solder work if the flux burns.

The silver soldering process is not too unlike regular soft soldering. The parts have to be clean and close fitting. The book says that parts must fit between 0.002 and 0.005, but 45% silver solder is fairly forgiving stuff. It will gap more than that, but try to the utmost to get within tolerance. There are no tricky joints on the Nina boiler. If you are careful, everything will fit fine.

When the soldering is done, let the part cool to room temperature. There is still a lot of flux left on the parts that needs to come off. Leftover, melted flux is chemically removed in a process called pickling. Pickling is an acid bath that dissolves the leftover flux with eroding copper. The pickle bath is 10 parts water and 1 part sulfuric acid (ordinary battery acid). I have not tried it, but citric acid works too. I understand that plain vinegar works too, although very slowly.

The first parts to solder in are all the bushings. They go in easily. Apply flux and solder them in. Heres what the top plate looked like immediately after the torch shut down.






The shiny area is the leftover flux. The blackened area is unfluxed. After about 15 minutes in the pickle tank, the plates are ready for the next step.






Solder the site glass bushings to the vertical barrel using the jig to align them. After pickle, remove the jig.






I used the site glass jig for each soldering step. Just as a precaution in case the solder re-melted for some reason. You dont want those bushings coming out of alignment. Remove and clean the jig after each soldering step. It gets crusty from the heating/pickle bath and you dont want the risk of it freezing in.

Thats enough work for now. Next time we will get into the heavy solder work.


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## zeeprogrammer (May 6, 2010)

Great post. Very helpful.

Thanks!


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## ozzie46 (May 6, 2010)

Very informative soldering post .Thank you. Keep up the good work.
 Watching with renewed interest.

 Ron


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## SAM in LA (May 6, 2010)

Bob,

Thank you for the detailed post on how you soldered your parts together.

Your parts are looking good.

I am following you build closely.

SAM


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## 4156df (May 6, 2010)

Bob,
Another very informative post. Nicely done. Do the support rivets require any special attention during soldering to insure they get sealed and soldered?
Dennis


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## kcmillin (May 6, 2010)

I really like this build. These little loco's are real Cool. So I thought I woulod subscribe to your thread so I dont miss any more.

I will be watching with much intrigue. Your post on silver soldering is great. I cant wait to try it now.

Would I be correct to assume that a standard propane torch does not have enough btu's to get the job done on such large parts? 

Kel


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## xo18thfa (May 6, 2010)

Thanks fellas.

I just noticed that I "fat fingered" the keyboard and did not get the last photo in. That's fixed.

Dennis: Yes they do. They need flux and a bit of solder when the top and bottom plates go on.

Kel: The "old school" method of soldering a boiler involved packing the boiler in burning coal or coke to provide background heat, then use a gasoline blow torch to get the last few degrees to melt the solder. Today some guys pack the boiler in burning charcoal briquettes, use a blower to get them hot and then use a MAPP gas torch to work the solder. So, yes you can, but not by itself. It sounds like a good method.


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## xo18thfa (May 10, 2010)

Today we are going to get the boiler weldment finished and ready for a pressure test. The first job is to solder the vertical and horizontal barrels together. This is the most difficult joint on the boiler, because it is the intersection of 2 curved surfaces. It is extremely difficult, if not impossible to solder this joint with the boiler remaining in one position. You will either have to solder it part way, let it cool down, clean it up and reheat the next part of the joint. Or reposition the whole assembly while it is hot and continue to solder the joint.

If you choose to reposition the boiler to continue work, keep an eye on the flux. Flux is good for an initial heat and usually 2 re-heats. By then its pretty much worked away. You will have to stop, let it cool down, pickle and start over. The solder can re-melt many times without affect.

Here is the initial set-up for this step. 






Not only do you have to worry about the technical aspect of soldering, but also the position of the barrels. They have to be square, plumb, level, flat and all that too.

One thing you learn quickly on this joint is torch control. The vertical barrel is more massive than the horizontal barrel. Apply more heat to the vertical barrel. Other wise the horizontal barrel heats up first, melts the solder and sucks it all away, while the vertical barrel is too cold to work. The hardest part of silver soldering is deal with odd joints and dis-similar sized parts. Just have to practice.

When the joint is done, remove from the pickle and clean under running water with a brass wire brush. Closely inspect the joint from both sides to ensure good solder penetration and a smooth overall fillet. This is the last joint you can visually inspect from the inside. If you get this one right, you can be confident that the others will turn out fine.

For me, I positioned this assembly on the top, both sides and the bottom to ensure the solder flowed all around. During inspection, the inside looked good, but there appeared to be a pinhole on the side. So it got fluxed up, positioned and that side re-soldered. 

Next is the soldering on the top and bottom plates. Here is the setup prior to the torch.






The site glass jig is back in for this job. Notice the short lengths of solder buried in the flux around the edge. The plates solder in with much trouble because flat surfaces are easier to work.  The small pieces of copper rod that the plates rest on need solder too. Some of them may solder on the own with the plates, but some wont. Let the assembly cool and then setup again to do these. Reposition the boiler while its hot and get them one at a time.

Now its time to solder in the flue. Put the flue in with the front flue sheet in the horizontal barrel. It is basically the same task as soldering the barrels together. Do the backhead end first.






Reposition and reheat as needed to solder the flue in.

The front end got a little more difficult. Heat radiates thru the barrel just fine but only melts the solder against the inside of the barrel. The flue stays too cold to solder. To fix that, we used a second torch (regular Bernz-o-matic propane) operated by Andy (my son) to run extra heat up the flue from the inside out. That got the flue hot enough to solder just fine. If that did not work, I was ready to simply cut off the smoke box and get at it directly. Unfortunately, I did not get a picture of that step. 

With everything soldered up, clean with a brass brush and have a good look. 






All of the joints on the Nina boiler are exterior. You can get to all of them for repair if you need to.

It was an all day job soldering the boiler together, mostly waiting for it to cool down and pickle. Next time we will do another air test on the motor and a pressure test on the boiler.


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## bearcar1 (May 10, 2010)

Terrific write-up and photos of the silver soldering process Bob, thank you for sharing it with us.

BC1
Jim


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## xo18thfa (May 12, 2010)

Thanks Jim.



The first air test on the motor was on an unregulated air source. It was just to test the motor and give it a good break-in. There was no way to tell what pressure it was running at. This time we will use a pressure gauge to find an actual operating pressure. Last time, we discovered that the spring holding the cylinder to the portface was way too weak. The air pressure lifted the cylinder off the portface. This time there is a stiffer spring.

For this test, cobble together a manifold with a pressure gauge close to the motor. Add in a stop valve, which is a modified refrigerator water valve and a swivel connection to the air hose. 






This is clearly not an ideal solution. A good quality air compressor with a secondary pressure gauge is the way to go. I am too cheap to get a good air compressor.

Hook everything up and give the motor another test.






The reason this manifold is not ideal is because as the motor rotates between power stroke and exhaust, the pressure gauge oscillates wildly. The pressure drops during the power stroke so the gauge is low. During exhaust the air pressure is cut off and gauge is up.

After a lot of experimentation, I determined that the motor operates best at 25 PSI. With no load on the wheels, the motor flies at about 2000 RPM. With a finger applying a load to the wheels, the motor speed drops to about 600 RPM and thru the gear reduction the wheels turn at about 140 RPM. At that speed, its powerful. The nasty gouge on my finger still hurts.

Knowing an operating pressure, it is now time to pressure test the boiler. The normal test doctrine is to plug all the holes, fill the boiler with water, and attach a hand water pump and pressure gauge. Pump the boiler to two times the operating pressure and hold that pressure for 30 minutes. Rather than use a hand water pump, I used the air compressor. I also tested the boiler to 80 PSI, instead of 50. In the unlikely event this boiler ends up on a different engine, I want it to handle a more usual Gauge 1 operating pressure of 40 PSI.

Using the same parts from the air test manifold, get the boiler ready to hook up to the air line. The boiler is full to the top with water.






Attach the air line and build pressure. Look for water leaks. 






I stopped the test twice because the plumbing junk insisted on leaking. After all that got fixed, the pressure was held at 80 PSI for 30 minutes. No leaks in the boiler. My son, Andy, who is equally knowledgeable in Gauge 1 live steam operations, witnessed the test. And to stake my reputation in a public forum, here is the gauge reading just before shut down






So what happens if there is a problem? The two problems I had on past boilers were an insufficient joint and a pinhole on a bushing. The insufficient joint prevented pressure from building up at all and shot a stream water all over the shop. The pin hole leak made it difficult to maintain pressure and sprayed a mist all over. If there are any problems, you will know it right away. The problem will be obvious and the test a failure. Dis-assembly the test and re-solder the bad spot. 

Out of curiosity, I did some theoretical performance calculations.

How fast (or slow) will it go? The wheels are 1.375 diameter. Each turn of the wheels moves the engine 4.32. At 140 RPM on the wheels, the engine moves 605 per minute. That works out to .84 feet/sec. The main line at our club track is 305 feet, so its about 6 minutes per lap. Thats good. Nina will certainly upset the high-speed mainline guys.

Does the boiler have enough steam producing capability? The motor has a .500 bore and .688 stroke. That is a volume of .135 cu in. Each revolution of the single acting, single cylinder engine will consume .135 cu in of steam. At 600 RPM the motor uses 81.05 cu in of steam per minute. At 25 PSI, 1 cu in water produces 640 cu in of steam. To produce 81.05 cu in of steam at 25 PSI, the Nina boiler will have to boil off .127 cu in water per minute. About 12.7 square inches of heating surface (water in contact with a surface heated by the fire) is required to do that. This boiler has about 15.3 sq in heating surface. It should have enough capability to produce all the steam we need. 

How long will it run on a single fill of water? Leaving about .500 open space at the top for steam accumulation, the vertical leg of the boiler holds 1.25 of water before the top of the flue is exposed. With an inside boiler diameter of 2.5, that is 6.136 cu in of water capacity available for steam. Based on the consumption calculation, the Nina boiler should produce 3927 cu in of steam at 25 PSI. That will give 29089 revs on the motor. At 600 RPM, that should give us 48.5 minutes of run time. If that ends up true, then we may need a separate fuel car.

Next time we will get on the smoke box front, stack and maybe the smoke box saddle.


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## xo18thfa (Jun 2, 2010)

After being sidetracked with a table saw rebuild project, its time to get back on Nina. The next phase is the front end of the boiler, starting with the smokestack. There are no drawings for the stack or other front end parts. Since they are mostly decorative, you may choose another style. Here is a shot of the stack cleaned up and ready to install:






The stack consists of 4 parts. The top cap, the stack tube, a base, and a base flange. The stack tube is a length of half-inch copper plumbing pipe, which is actually 5/8 diameter. Cut a piece to desired length and square both ends.

The base has an unusual shape. There is a rounded portion on the bottom end that allows for a smooth fit with base flange and the boiler smokebox. The rounded portion is the most difficult to do, so lets do that first. Everything else after that is straight turning. 

The base starts out from 1 square brass. Cut a 2 or so length. We are going to cut the rounded bottom using a modified horizontal boring technique. Modify the wooden jig used early to cut the large holes in the boiler barrels. We will need to fabricate an in-line boring bar. An 8 to 12 length of 3/4" steel rod will do fine. Face both ends and center drill. Drill a hole for the cutting tool and tap a set screw to secure the cutting tool. Here is the holding jig and boring bar ready to go.






Secure the jig with brass stock to the lathe cross slide.  Set the cutter in the boring bar to swing the exact radius needed for the base flange. In my case, the base flange came from a copper coupling pipe 1 5/8 diameter. So set the radius on the boring bar to 13/16. Mount up the boring bar in the 3 jaw chuck and stabilize the other end with the tailstock.






Engage the half nut on the lathe carriage, taking about .020 depth cut on each pass. Continue taking .020 deep cuts until there is a clean cut across the entire bar. Cut both ends of the brass stock. We will need the other side later on for the smoke box saddle. Before you know it, its done.






I was very surprised how well the wooden jig worked out. It was rock solid on the cross slide, no chatter at all and the cut turned out glass smooth.

Now center up the square stock in the 4 jaw chuck and turn a decorative profile.






Next, drill and bore a 5/8 hole to accept the stack pipe.






Part off the stack base from the square stock. Turn it around in the 3 jaw chuck and finish the parted end. A soft round over with a file is all I did.






For the base flange, bore a 5/8 hole in a length of copper coupling pipe. The coupling pipe has an inside diameter the same as the outside diameter of the horizontal barrel on the boiler. Bore the hole the same way as you did on the boiler.






Cut out a section of the coupler pipe and round over the corners with a file. Drill #51 sized holes in the corners to accept 0 x 80 machine screws for mounting the stack to the smokebox. Heres the stack base and flange ready to silver solder to the stack tube.






The top cap is a straight decorative turning. Turn the outside to profile, bore for the stack tube, everything just like for the base.






Finally, all the stack parts done. 






Silver solder the stack, pickle and clean up. Hang it on the boiler for a look-see.






I think it turned out very nice. The stack is not hard to make, but it is very time consuming. It involves a lot of tool set-up and chuck changing on the lathe. Next time we will do the smokebox saddle and the smokebox front.


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## 4156df (Jun 2, 2010)

Bob,
Very neat approach on the base. Thanks for showing it.
Dennis


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## xo18thfa (Jun 3, 2010)

4156df  said:
			
		

> Bob,
> Very neat approach on the base. Thanks for showing it.
> Dennis



I saw in an old UK home shop machinist book the use of wood packing to in-line bore a steam engine cylinder. I thought no way it would work. But, maple wood machines very well to a reasonably close tolerance. The wood set-up worked fine. Need to try it on steel or cast iron yet.


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## xo18thfa (Jun 6, 2010)

Today we will continue with the front end of the boiler and get the boiler mounted on the engine frame. The smoke box saddle uses many of the same construction techniques as the smokestack. Fortunately, the saddle is not as complicated as the stack, and we already have the most difficult part done. Start by setting the boiler on a flat surface and measure the distance from the bottom of the smoke box to the table. The overall height of the saddle must be such that the boiler sits squarely on the engine frame without binds or distortion.

Cut out the saddle parts as you did for the stack. Drill a hole for a #2 machine screw in the center of all the parts:






The machine screw holds everything together while soldering. Silver solder the saddle together and remove the holding screw.






It is better to use 2 or more screws to hold parts together for silver soldering. Assemblies have a bad habit of loosening up just about the time the solder wants to flow. The saddle base decided to squirrel around on me right after the solder melted. Fortunately I was able to keep it hot and tap it back in place.

Next is the smoke box front. It is basically a turned ring from 1/4" thick brass plate with a hinged door. Rough saw a slab of brass and drill a 5/16 hole in the center. Sandwich the brass stock between two hex nuts on a bolt. Chuck the assembly in the 3 jaw and turn the outside to the desired shape. About 3/16 of the smoke box front fits inside the smoke box. Turn this portion to a good smooth fit.






Put the reverse jaws in the 3 jaw chuck and turn out the bulk of the inside of the smoke box front. Leave about 1/16 thickness on the front and 1/8 on the walls.






Now chain drill and file an opening in the smoke box front for the door. If you go with a round door, turn it out on the lathe. Cut out and shape a door. The door should be about 1/16 larger all around then the opening.






The door is functional, so we have to make up some hinges. They are simple strap hinges made up from 1/8 x 1/32 brass strip. Bend the strip over a 16 gauge (1/16 dia) nail.






Then finish the hinge by squeezing in the vice. You have to practice this a few times, but soon they come out nice.






Trim the hinges to final size. Drill the hinges, door and smoke box front for either a 0 x 80 or 00 x 90 machine screw. I happen to have some scale 00 x 90 model hex bolts leftover from another project.






Silver solder the hinges to the door and smoke box front. The little 00 x 90s probably wont hold to well on their own. Fashion up a cutesy handle. This handle is fabricated from a 2 x 56 screw, a small turned hub and a 16 gauge nail for a knob.






Attach the smokestack and saddle to the smoke box. The machine screws on the back go thru the smoke box and are fixed with nuts on the inside. The screws on the front go into tapped holes on the rim of the smoke box front. 






I think it looks very nice, if I do say so myself.

Mounting the boiler to the engine frame is an exercise in locating and drilling. Center the boiler on the frame. The front to back position is not too critical, just dont interfere with the manifold on the engine. The boiler is secured with two 6 x 32 screws going into the bind bushings on the bottom of the boiler. The smoke box saddle has four 0 x 80 screws and bolts.






Its really starting to look like a steam locie now. I guess its time to start thinking about the style of the engine. I have absolutely no artistic talent so I dont know. Nina is going to have an open top wooden cab, thats all I know. After that, I will have to plagiarize ideas. Paint color, trim, I have no idea. Suggestions are very welcomed.

The last 2 mechanical phases are the plumbing and burner. The plumbing is straightforward. The burner has some options. A torch type burner like Mr Glaser used on Cracker or a conventional poker type. I am thinking about trying a bottom feed fuel tank with a pre heat loop. Maybe adding a secondary control valve. That would be different.

Anyway, next time well either get started on the plumbing or play with fire.


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## zeeprogrammer (Jun 6, 2010)

xo18thfa  said:
			
		

> I think it looks very nice, if I do say so myself.



You're not alone. It's wonderful work. Very impressive. It's the kind of work I dream of being able to do.


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## Deanofid (Jun 6, 2010)

Yes, it does look very nice, indeed! Great build thread, Bob. When it comes to the write up and
pictures, you really know how to do it up in good fashion. 
This is coming along well!

Dean


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## 4156df (Jun 6, 2010)

Bob,
I have to echo Bob's comments. Great write-up and very nice looking build.
Dennis


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## xo18thfa (Jun 13, 2010)

Thanks guys. Its getting exciting. Cant wait to see this baby on the rails. 

For Dean: I ordered some watch bearings from the company you recommended.  I got some L01 and L56 (I think, the 2d and 3rd smallest bores). They will be the gas jets for the burner. Most likely a bar burner used widely in Gauge 1.

Its time to get started on the plumbing. Engine plumbing consists of the safety valve, throttle valve, site glass, pressure gauge, pressure gauge syphon, lubricator, steam dry pipe and exhaust. Plumbing is a lot of work. Fortunately, many plumbing parts are commercially available, which cuts down on the work. For this engine, we are going to scratch build all of it. At first, I thought about skipping the pressure gauge, but now I am thinking about adding one. There is an extra bush on top of the boiler we could use. Well think about it.

For now, lets get started with the lubricator. Steam engines, like gasoline engines need oil in the cylinder. Oil is injected in the steam flow and carried onto the cylinder. There are 2 ways to get oil into the steam flow. One is by a slow acting mechanical pump. The other way is with a hydrostatic lubricator. A hydrostatic lubricator is nothing more then an oil tank with the steam pipe going thru the tank. On the top of the steam line is a very small hole. Here is a schematic.






Steam escapes into the oil tank thru the small hole. It condenses back to water and drops into the tank. Water is heavier then oil so it settles to the bottom, and raises the level of the oil. Eventually the oil level raises to the small hole in the steam line. The oil seeps into the steam line, gets atomized by the steam and is carried off to the cylinder. Real steam oil is extremely heavy gear oil, usually 460 weight. The addition of tallow fat helps the oil atomize. Hydrostatic lubricators are absolutely bullet proof. They work every time. 

The combination gear and chain drive transmission used on Nina requires that the steam inlet be on the front side of the engine and exhaust on the back. The steam and exhaust pipes cross each other. I did not think about that mess. It made a difficult placement of the lubricator. Normally the lubricator goes inside the cab, sort of out of sight. Our lubricator is going directly on top of the horizontal boiler barrel. It will be different.

Heres the finished lubricator, ready to go on its stand. There is no drawing for the lubricator. As my old college professors always said, it is left to the student as an exercise






The large plug is the fill/clean out. The small plug is directly over the small hole in the top of the steam pipe. In the unlikely event the small hole plugs, we need to get to it to clean it out.

Start on the lubricator by turning the tank from a piece of 1 square brass stock. Bore a flat bottom hole 11/16 deep and as wide as possible without poking thru the sidewalls.






A flat bottom hole can be hard to do with a regular boring bar. Instead use a regular end mill bit instead of a boring bar. The end mill does just fine.

Cut off the tank from the bar stock and face the bottom smooth. Next, tap 0 x 80 holes in each corner on the top and the bottom of the tanks. The tapped holes on the top are for the lid and the holes on the bottom are for mounting on the stand.






You have seen the picture of the tap handle several times. I cant emphasis enough how important a good tap handle is in the shop. You cant tap a 0 x 80 hole by hand, no way.

Now make the steam pipe. Cut and face a 1 1/2" length of 1/4" brass rod. Drill clear thru with a #30 drill. Run a die over both ends for a length of about 3/16. Drill a 1/4" hole in the tank 7/16 from one edge and 3/16 down from the top. We want the steam pipe slightly off set so it clears the fill plug. Silver solder the pipe into the tank.






The top lid is from 1/16 brass plate. Cut a 1 1/8 square piece so it overhangs the tank just a bit. Using a block of hardwood with some #8 sheet metal screws to secure the top lid, drill #51 holes in the corners to match the 0 x 80 holes in the tank. Drill a 3/16 and 5/16 hole for the plug bushings.






It is really handy to have an X-Y table on the drill press or a milling machine. The graduated table knocks these parts out super accurate and so quickly.

Using the top lid as a guide, drill a #60 hole in the steam pipe, top side only.






Turn bushings out of brass for the plugs. The fill plug is 1/4" x 40, just like the boiler bushings. The clean out plug is 4 x 40 or 6 x 32, whatever is handy.






Secure the top lid to the tanks with 0 x 80 screws in the corners. Silver solder the lid to the tank.






Finally, silver solder the bushings into the top lid. Make some plugs with washers and the lubricator is done.

Next time we will get on the lubricator stand and get everything mounted. I dont know when the next update will happen. I have to report for jury duty on Monday. Federal District Court, must be a biggy. It may last 4 to 6 weeks, they said.


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## Deanofid (Jun 13, 2010)

I must be doing it wrong.. My lubricators all come out round. ; )

Just pulling your leg, Bob! It came out great.

Dean


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## zeeprogrammer (Jun 13, 2010)

xo18thfa  said:
			
		

> I have to report for jury duty on Monday. Federal District Court, must be a biggy. It may last 4 to 6 weeks, they said.



When asked a question..just say "hang 'em"...that should get you out.

But knowing you'll do the proper civic duty...I'm still hoping you're back quicker than you think. I really enjoy your thread.


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## xo18thfa (Jun 14, 2010)

Dean: Dang, I did not think of that. It's round inside.

Carl: I got excused. They have you call in the night before to check. They excused two whole jury pools. I bet the charges were dropped or the trial postponed.


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## xo18thfa (Jun 18, 2010)

Today is the second half of the lubricator. We are going to fabricate the lubricator stand and get it mounted on the boiler. The stand for the lubricator is basically the same process as with the smokebox saddle. The stand consists of a top and bottom plate and a curved spacer in between.

All the parts fabricate the same way as the saddle. You will have to set up the between centers boring bar to carve out the round portion just as before.







The only difference from the smoke box saddle is the spacer for the lubricator stand has the bulk of the interior material removed. Just for looks.

The lubricator assembly gets strapped to the top of the boiler. To make the straps, coax lengths of brass strip around a piece of pipe to the exact diameter of the boiler barrel. Cut the ends of the straps so they meet exactly. The brass straps can be from 1/32 thick strip, either 3/16 or 1/8 wide. If the brass strips get too springy and uncooperative, heat them to dull red and quench in water. That will soften them up.






Silver solder the stand assembly together. Do it in stages. First solder the base plates and spacer. Then solder on the straps. Finally, solder on a 3/8 length of 1/8 OD, 3/32 ID brass tube directly over the ends of the strap. This is the stand assembly, upside down.






Now with a fine saw, cut thru the brass tube and strap.






Attach the lubricator to its stand with some 0 x 80 screws. Disassemble the boiler and slip the lubricator assembly over the boiler barrel. Size 0 x 80 machine screws fit nicely inside a 1/8 brass tube. Sinch up the screws just enough to hold the lubricator in place.






Reassemble the boiler to the engine frame. With the lubricator in place we can mock up the steam and exhaust piping.






That looks cool. At least the horizontal boiler barrel has something useful to do. Brightly polished brass straps should look nice against a black boiler shell.

Next time we will do a safety valve and maybe start on the site glass.


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## Deanofid (Jun 18, 2010)

It's looking good all put together, Bob.

Dean


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## shred (Jun 18, 2010)

Very nice. Much fancier than my little Cracker. The lack of lubricator in those plans is a bit of an oversight I think, it could use one for longer runs.


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## zeeprogrammer (Jun 18, 2010)

Nice Bob. I'm enjoying this thread very much. Learning a lot.


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## xo18thfa (Jun 27, 2010)

Thanks guys. It's coming along. It's like eating an elephant, just do it one bit ant a time.

Dean: I ordered some of those watch bearings. Hopefully burner jets will come along soon.

In researching miniature safety valves, I looked at work by K.N. Harris, Martin Evans, LBSC, Tubal Cain and Kozo Hiraoka. The Nina boiler is so small in terms of steam production that it is off the low end of all the charts, graphs and formulas. I came to the conclusion that the only real design criterion is that it must release steam faster then the boiler can produce it. After looking at Kozos work some more, I think this one will do that.

This valve is the usual stainless steel ball type. Our valve will use a 1/8 diameter ball against a 15-degree beveled seat. It is not a true safety valve in terms of a pop valve; its more of a pressure release valve. Real pop valves close quickly when the pressure drops to the safe level. This type closes sometimes, sometimes they dont.

Here is the exploded view of all the parts.






Here are the drawings for the safety valve:

http://1stclass.mylargescale.com/xo18thfa/Nina%2002/Safety%20A.jpg
http://1stclass.mylargescale.com/xo18thfa/Nina%2002/Safety%20B.jpg

Start with the valve body. Normally the valve body is turned from a single piece of hex brass stock. A specially sharpened D bit cuts the 15-degree for the ball seat. I am going to try an experiment with the valve body and make it in 3 parts. I want to do away with the special D bit and make all the parts with standard lathe tooling.

Before starting on the valve body, there is an important accessory you need for your lathe. We have used a tap holder for threaded holes, now we need a die holder to cut threads on a rod. While dies holders are commercially available, you can make your own. Here is the temporary one I made 30 years ago.






My die holder is an old 1 bolt, cut off, with a 1/2" hole drilled thru it and a recess for a 1 diameter die. Dies under 1/4" are usually 1 diameter. Smaller dies are 13/16. I made an adapter to hold smaller dies. The short length of rod goes in the lathe tailstock and the die holder slips over. A set-screw holds the die in the holder. Heres the die holder in the lathe ready for work.






The tailstock lines up the die just like a tap holder does the tap. To use it, hold the lathe chuck stationary with the left hand and turn the die holder with the right. Go about 1/3 turn and back out to clear the chips. Use oil, even on brass. After a while you get in a rhythm with this thing, and threads cut in a hurry. It is impossible to cut accurate threads on a rod by hand. Invest in a ready made die holder or fabricate your own.

First part to make is the valve seat. Chuck a length of 1/4" brass rod in the 3 jaw. Drill and #39 ream about 1/2" deep.






The reason for #39 is that the hole thru the valve seat is 80% the diameter of the ball. #39 is .0998, which is the closest to 80% of 1/8. You could get by with a 3/32 ream, which is probably what the commercial makers do.

Using the die holder, cut a 1/4 x 40 thread for about 1/2" long.






Next, set compound slide on the lathe to 15 degrees and face off the end of the valve seat. Run the bit outwards to pull burrs away from the reamed hole. Face deep enough to get into the good, clean reamed hole. This 15-degree edge needs be clean and sharp. Part off the seat to 3/8 length.






Now make the bonnet nut. Drill and tap 3/8 hex brass with 1/4 x 40. Turn a nice chamfer on the edge. Rough hacksaw it off.






Putting a little nut like this in the lathe chuck to face off the rough-cut is nearly impossible to do. Instead make a chucking spigot with a jam nut.






Assemble the work piece on the spigot, secured with the jam. Chuck it up and face it clean.






Make these kinds of spigots as you need them. Over time you will end up with youll end up with a set. This particular spigot has 5/16 x 40 on the other end.

The valve bonnet is an easy turning job from 5/16 hex brass.






Heres all the parts for the valve body.






Assemble the body by jamming the bonnet nut and the bonnet.






Thats enough for today. Next time we will finish the safety valve. The next installment will have some very serious mathematical content. Have some scratch paper, stubby pencil and dirty eraser ready. No calculators allowed.

Take care.


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## xo18thfa (Jun 30, 2010)

In the last installment we carefully machined a sharp 15-degree bevel on the edge of the ball seat. Now it is time to seat the ball to the valve seat. The ball we use is a precision stainless steel bearing ball. It has very close tolerances and a hardness approaching Chinese Arithmetic. It should do fine.

To seat the ball, set the valve body on a flat hard surface. Drop in a ball. Use a length of brass rod as a drift punch. Get everything lined up and give the drift a pop with a hammer. Here is the set up.






The ball will make a slight spherical impression in the ball seat. The question is: how hard do you hit the drift with the hammer? I dont know how to describe it, medium light(?) If done right, the ball will make an air tight seal if you suck on the bottom of the ball seat with your mouth. There should also be a very slight indentation left on the seat edge by the ball.

The valve stem comes next. It is a straight turning job from 1/8 brass rod. Turn the stem between centers on the lathe. Drill a #60 hole in the end of the rod to a depth of about 1/16. Follow up with a 5/32 drill bit to cut a shallow V notch in the end of the stem to center the ball over the valve seat. The #60 hole serves as a center hole for the lathe tailstock.






The final part to make is the stem adjuster nut. This nut bears against the valve spring and adjusts the valve to open at the desired pressure. Pressure adjustment on this valve can go from zero to total lock down.

The adjuster starts out from a short length of brass rod. Thread the rod with 1/4 x 40 for a length of 1/4". Drill a #50 hole for a smooth slide fit with the valve stem.

The safety valve drawing shows six holes, #57 in size, drilled in a hex pattern thru the nut. These are steam relief holes allow the escape of steam thru the valve body when the ball lifts. These holes are needed or the valve doesnt work. The are spaced at 60 degree intervals from the center. They lay on what is called a pitch circle. The diameter of the Pitch Circle in our case is 9/64 or .140. That puts them about half way between the outside edge of the center hole and the root of the thread.

There are a number of ways to layout and drill the relief holes.

1. Use a CNC machine.
2. Set up a rotary table or some indexing device on the mill to space out the holes on a 60-degree interval.
3. Use a drilling spindle on the lathe cross slide and index the lathe on 60-degree intervals. 
4. Do a mathematical bolt circle calculation and use the X  Y table on the milling machine. 
5. Layout the holes by hand, center pop and drill.

Option #5 is easiest way to go and will produce a perfectly satisfactory result. But, instead of doing it the easy way, we are going to use method #4. The challenge is converting angles from the center to X  Y coordinates for the milling table.

The following diagram shows the layout of the relief holes as if the stock were clamped in the mill vice. Holes #1 and #4 are easy to drill. They are simply plus and minus 0.070 from the center. Holes #2, #3, #5 and #6 require a combination of X and Y movements. It is those values of X and Y we need to find.






The diagram shows a convenient 30-60-90 degree right triangle that includes hole #2. As you know from your High School trigonometry class, the sine of an angle multiplied by the hypotenuse give the length of the side opposite the angle. In this case, the sine of 30 degrees is 0.500; the hypotenuse is 0.070. The Y distance from the center to hole #2 is 0.035. Similarly, the cosine of an angle multiplied by the hypotenuse gives the length of the adjacent side. The cosine of 30 degrees is 0.866, hypotenuse is still 0.070. They X distance from the center to hole #2 is 0.061. Since the remaining holes are equally spaced around the pitch circle, the values of Y=0.035 and X=0.061 will reach all of them.

Lets drill some holes. Clamp the adjuster nut stock in the mill vice and center it under the mill spindel. Use a center in the drill chuck to center the stock. Lower the center into the hole and adjust X and Y until center. You eye is a precision instrument and will get this right on.






Traverse the Y-axis by plus and minus 0.070 to drill holes #1 and #4. Use a center drill to spot the holes before switching to the smaller bit.






Now, using the values of Y=0.035 and X=0.061 traverse from the center to drill the remaining holes.






They came out spot on. The lead screws on my mill have a lot of backlash in them. That prevents me from simply running around and drilling the holes. I started from the center on every hole.

The last part is the spring. It is a precision stainless steel spring, with a diameter of 0.120, length of 0.250 and a wire diameter of 0.016. It has 5 full turns. The spring and ball came from McMaster Carr.

Here is the safety valve ready to set.






The final thing to do on the valve is to set for pressure. We will do that later when we fire the boiler on steam. Next time we will work on the site glass.


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## 4156df (Jul 1, 2010)

Bob,
She's a beauty! Thanks for taking the time to post. Very interesting and informative.
Dennis


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## bearcar1 (Jul 1, 2010)

"I hear the train a comin' ........ she's roaring(?) 'round the bend........"


Won't be long now. Looking real good, I do appreciate the fine work on that safety valve.


BC1
Jim


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## xo18thfa (Jul 3, 2010)

Thanks Dennis and Jim. I am getting nervous. It's close to steam test time. I hope this thing works.


The design for the site glass, or water gauge is from LBSC. It is a design that he used on many of his Gauge 0 live steamers. His original plan called for 1/8 diameter glass tube. 5/32 glass is more widely available and I have a bunch of it. So we will increase LBSCs design by 25% to take advantage of larger glass tube.

Here is the drawing. It is LBSCs drawing, but I added the plus 25% dimensions.






The valve on gauge lower end is a blow down valve. The purpose of it is to ensure a proper reading in the gauge glass. Weird science happens sometimes in these small gauges that prevent accurate readings. Opening the blow down causes the water glass to drain out. Closing the valve allows the glass to fill back up to its actual level. While operating the engine, occasionally crack the blow down open for a half-second and close it. That will ensure an accurate reading. Sometimes small gauges work fine without a blow down. Sometimes they dont. Its better to have it and not need it, then to need it and not have it. Besides, they are too easy to make, so go ahead and do it.

Start work with the gauge lower end. It is a brass and silver solder fabrication. Thread all the required parts before silver soldering.






The boss for the gauge glass goes into a blind hole. The boss for the drain is straight thru. You can do them either way. Going straight thru is better I think. It ensures the silver solder goes all the ways thru and makes the part solid. I cut the lower end stock off a bit too short on the drain end. Leave it about a quarter inch longer then I did, you see why shortly.

Silver solder the lower end together.






Instead of threading the lower and upper end into a shoulder, I decided to use a jam nut instead.

Chuck the lower end in the 3 jaw by the drain end. This is why you need to leave it a bit longer. Fortunately I was able to grip it securely. Drill #31 9/16 deep. This is the water passage.






Grip the lower end in the drill vise. Drill #19 1/8 deep. This is a generous O.D. fit for the gauge glass. Drill # 40 just breaking into the water passage. #40 is the I.D. of the gauge glass.






Make up a female threaded chucking spigot to accept the gauge lower end.






Chuck up the gauge lower end in the spigot. Machine of the excess material to the final length of the gauge lower end. Drill and tap for #4 x 40 to a depth of 3/8. Lastly, drill #55 thru into the water passage.






Make a blow down valve spindle from a #4 x 40 machine screw. Turn the screw down to 0.080 diameter for a length of 3/16. File or turn a 60 degree included angle point on the spindle. Loctite or silver solder a knurled nut to the spindle. With that, the gauge lower end is done.






Next, fabricate the gauge upper end, its done the exact same way as the lower end. 






Silver solder the parts together and machine as with the lower end.

The packing nuts for the glass tube are actually a silver solder fabrication. Drill and tap a 1/4" x 40 hole into some 5/16 hex brass. Part off a 5/32 length. Cut some brass scrap, any size will do.






Silver solder the threaded hex to the scrap. Use the least amount of solder possible. Too much solder can capillary up into the thread and ruin it. Find that threaded male chucking spigot you made earlier.






Chuck the blank nuts and spigot in the lathe. Drill #19 thru.






With the nut still on the spigot, face to a total length of 3/16. Turn the waste brass off. At this point you can file the remaining brass off so the whole nut is hex shape. I left it round, looks OK.






Make a plug nut for the gauge upper end. I could not find my 10 x 32 die, so the plug is a machine screw silver soldered into 1/4" hex brass. Of course, after doing the plug, I found the die. Cut a 1 5/16 length of glass tube. The best way is with an emory cut off wheel on the Dremel tool. Just lightly score the tube all around. It will snap off cleanly. The site glass is all done. 






Put it on the boiler for a look see.






Thats lookin sexy. We will eventually do a drainpipe for the blow down. Probably after the cab is done.

Plumbing is almost done. Next time we will get on the throttle valve.


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## bearcar1 (Jul 3, 2010)

Nice!, Bob. A really slick write up on how to make that blow down valve. I'm going to copy that one down for future reference. I have always questioned the ability of some of those single tube gages for being accurate. Usually OK I suppose but still, this method insures a good water level display.

BC1
Jim


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## zeeprogrammer (Jul 3, 2010)

Absolutely interesting Bob. I really enjoy your posts.

I have to ask a newbie question...I've seen a couple of members make a glass water level gauge. That's supposed to show the amount of water left in the boiler right? But what about the pressure? Why doesn't the glass break? I'd really appreciate a little education on that.

Thanks.


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## Deanofid (Jul 3, 2010)

Nicely done gauge, Bob. It looks great on the boiler!

Dean


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## xo18thfa (Jul 3, 2010)

Thanks guys.

Dean: I can't wait to try the watch bearing trick for the burner. They are sitting on the bench ready to go.

Jim: I think blow downs should be used. I don't recall blown downs available on any commercially made gauges, except in the large "ride-on" sized train engines.

Carl: The glass is pretty strong and can take the pressure. I've never seen one break during operation. Usually they get dumped and break. If one breaks under pressure, all the steam and water goes shooting. There is nothing to stop it. Actually, most of them are broken during installation.

The water gauge shows the water level in the boiler. The pressure is measured with a pressure gauge. The miniature steam suppliers sell very small pressure gauges. They are 3/4" or 1/2" diameter. I use small pressure gauges from fire extinguishers. They are kind of big, but work fine and are very cheap.

Pressure gauges connect high on the boiler, above the water level. In the pic below, there is a "U" shaped pipe called a siphon. Steam goes into the siphon during warm up and condenses back into water. The water remains in the bottom of the siphon and blocks steam from directly going into the gauge mechanism. 

The original plan was to not have a pressure gauge on this engine. Maybe I will put one on. I can modify the boiler fill plug to accept a gauge.

Thanks, Bob


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## SAM in LA (Jul 4, 2010)

Bob,

Very nice level gage.

Does anyone ever make the sight glass with valves between it and the boiler?

SAM


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## xo18thfa (Jul 27, 2010)

Sam: I have never seen sight glasses like that in Gauge 1. The "ride-on" sized engines sometimes have them. I have never seen a gauge glass break under pressure either. I am sure it could happen, but not so far.

After a short break for another project, its time to get back on Nina. Throttles for many Gauge 1 engines are simple screw down valves. Lets do something different and make a piston style throttle. Heres the completed throttle ready for the boiler. This view is from the bottom. The hole towards the left end goes into the boiler. The threaded portion facing downward goes to the engine.






Heres the drawing for the throttle assembly:

http://1stclass.mylargescale.com/xo18thfa/Nina%2002/Throttle.JPG

Fabrication of the throttle is almost exactly the same as the water gauge. The throttle body is a brass/silver solder fabrication, consisting of 3 parts. Here they are:






Silver solder the throttle body parts together to form a pseudo casting.






Chuck the throttle body in a chucking spigot. Drill and ream 5/32 thru.






Grip the throttle body in the drill press vice and drill both passages 1/8. Everything so far, just as the water gauge.






The throttle spindle is from 5/32 stainless steel. Lightly polish the rod with fine emory cloth and oil for a smooth sliding fit in the throttle body. Chuck the stock in the 3 jaw, securing the end with the tailstock. A #60 drill is sufficient for a center hole. Turn the slot in the spindle. Square the corners with a parting tool.






The fork end of the spindle assembles the same way as the piston and piston rod. Use a 2 x 56 machine with a dab of Loctite to secure the spindle and fork. The usual practice is to hacksaw and file the slot in the fork. Lets try something different. Make a little holding jig for a length of 3/16 dia brass rod. Use a parting tool to take a plunging cut to form the slot. A set-up something like this.






This is way easier then with saws and files. Trim the fork to length and tap the end for 2 x 56. Assemble the spindle rod and fork.






The remaining parts are straightforward. The two links are from 1/32 x 1/8 strip brass. Drill them identically with #53 drill. #53 is a very close fit for 0 x 80 machine screws. The throttle handle is from 1/16 x 3/16 strip brass. The only thing critical about the handle is the 3/8 between holes. Jazz the throttle handle as desired. Two cap nuts are needed. Make them both the same way as for the water gauge glass. One cap is blind to seal the end of the throttle body. The other is a gland nut drilled #19 for a very generous fit for the spindle. Finally, a jam nut to lock the throttle body to the boiler bushing. Here are all the parts:






Assemble the throttle. The pivot points are all 0 x 80 machine screws. Hang it on the boiler.






Thats lookin sweet.

The full throttle position is with the handle straight back, as shown in the photo. The throttle closed position is either full left or full right. Either way shuts it off.

Next time we will get on the steam and exhaust piping and finish up the plumbing.


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## xo18thfa (Aug 1, 2010)

There are probably as many ways to install steam and exhaust piping as there are ways to cook chili. The primary method I use is a nut to compress a flange against a flat fitting face. A small, thin Viton O ring serves as the seal between the flange and the face. Viton is a reasonably high temp rubber that works wells in Gauge 1 steam applications. This method has worked well for me on all my scratchbuilds, so well stick with it.

An alternate method to install piping is with a banjo bolt. Banjo bolts are used to install pipes into boiler bushings, and in our case to the engine manifold. A banjo bolt is essentially a very thick washer with a tube soldered into it. The banjo is attached to the bushing with a special hollow and cross-drilled bolt. More on banjo bolts in a moment.

First up are some 90 degree elbows. We need 2 Street Ells (male-to female thread) for the lubricator and one as a fitting to go thru the smokebox wall. The elbows fabricate and solder together just as with the water gauge and throttle. The street ells consist of 3 parts; all threads are 1/4" x 40 TPI. Here are the parts for one and another just out of the pickle tank:






The exhaust elbow thru the smokebox has a long leg and a short. The long leg goes thru the smokebox wall and is secured with 2 jam nuts.






For the piping, start at the throttle and work towards the exhaust end. From the throttle, I came out with 5/32 diameter thin wall copper tube. 1/8 will probably work fine, but I did not have enough 1/8 on hand to do the whole engine. Anneal to copper tube to soften it. Then with your favorite tube bender, bend and trim the tube until it fits between the throttle and the lubricator. Make up two nuts just as with the water gauge glass nuts. Turn and part off flanges about 1/32 thick and diameter that is a good close fit inside the nut. Here are the parts for the first pipe.






The O-rings are 3mm inside diameter and 1mm wall. They are available from McMaster-Carr and fit perfectly for this job.

Slip the nuts over the tube and silver solder the flanges.






The next pipe from the lubricator to the engine manifold has a nut-flange on one end and a banjo on the other. Heres the drawing for the banjo bolt.

http://1stclass.mylargescale.com/xo18thfa/Nina%2003/Plumb%20Banjo.JPG

And here it is soldered up and ready to install. This is 1/8 OD, thin wall copper tube.






And from the manifold exhaust side forward to the smokebox elbow.






Now install all the pipes, starting at the throttle. There are no O-rings used for now. Those get out in at final assembly






I decided to change location of the throttle by placing it on the side. That centers the handle better, should work out OK.

And now install the 2d-steam pipe and exhaust pipe. Loosening the lubricator helps get the pipes installed.






Last pipe to go in is the blast pipe. Its not really a blast pipe; it just gives the exhaust steam something decorative to do. Install it with a nut and flange. Trim the length so it is near the top of the stack.






So here is where its at so far.






Lastly, fabricate a water fill plug for the last bushing on top of the boiler. I am thinking about making up a riser section with a nipple on the side and the water fill on top. Use the nipple for a pressure gauge outlet. 

Looks more like a moonshine still then a steam locomotive.

The plumbing phase is all done. Next is the butane fuel system. I am trying to figure out where to put the fuel tank. Either inside the open top cab, or on the fender, forward of the flywheel. What do you guys think?


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## ariz (Aug 3, 2010)

xo18thfa I don't know where to put the fuel tank, I'm sorry, but replied anyway to say that your work of silver soldering and plumbing is admirable :bow:

the result is a fascinating ensemble, really a work of great craftsmanship, very beautiful and well shapely

thanx for sharing it


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## kustomkb (Aug 3, 2010)

You're doing some really nice work there Bob!

What a great idea, slotting the fork like that. Man, ya really do learn something new everyday.


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## xo18thfa (Aug 6, 2010)

Thanks guys: It's coming down to the home stretch for sure.

Just a short update on two little jobs completed before starting on the fuel system.

A good buddy in Australia sent me a note saying that their boiler codes require a means to lock the pressure setting on a safety valve.  It is possible over time for the safety to jiggle loose and come apart. The usual method to lock the safety is with a jam nut. Its the right thing to do and the fix is so simple; there is just no reason not to do it. 

The fix requires a simple modification to the existing valve body and fabrication of a jam nut. Chuck the valve body in the chuck spigot and turn off 3/32.  Thats it. With the jam nut heres our safety valve mod:







The safety is not set for pressure yet. It gets set later during a steam test of the boiler.

The second job is a new throttle body. The boiler nipple on the old throttle body is too short, making it difficult to install on the boiler. The drawing I made for the throttle body is correct. If you follow the drawing, the throttle body will install just fine.

In making the new throttle body, I used the fly-cutter method to machine the linkage tab. Make a threaded jig to hold the nipple.






Use the parting tool to shave down the sides of the linkage tab. It worked out sweet.






The new throttle body sits taller and is easier to get on the boiler.






Next week well start on the fuel system. The fuel tank is going inside the cab. The other day on the Internet I found a micro sized pressure regulator that might be worth an experiment. If Nina runs good, it may end up a test bed for do-dads like a pressure regulator. So for now I want to keep the fender position available.


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## joe d (Aug 6, 2010)

Bob

Your project just keeps getting better and better... :bow:

I've been enjoying following along, and have learned a lot. 

Thanks!

Joe


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## 4156df (Aug 6, 2010)

Bob,
Been away for awhile, so just caught up on your posts. Very informative thread. Keep it coming, please.
Dennis


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## zeeprogrammer (Aug 6, 2010)

Bob, thanks for the info on the sight glass.

This is a really interesting thread. I appreciate the tips and techniques.


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## GailInNM (Aug 6, 2010)

Bob,
"Nina" is looking really nice. I am enjoying the thread.

On the last Gauge 1 loco I built I bolted the gas tank on the footplate about 1-1/2 inches from the burner mount which also supported the rear of the boiler. Vertical cylinder butane tank with a bush in the bottom so it pulled down solid to the footplate. I wanted it to stay warm so the falling gas pressure due to he cooling of the gas as it was drawn off would be offset.

The heat conduction from the burner/boiler was greater than anticipated and the tank would warm up on long runs so the tank pressure would rise. This would "build a bigger fire" and the tank would warm more so every lap around the track I would have to turn down the fire. Final solution was to put a piece of 1/16 ply between the fuel tank and the footplate. Kept the tank temperature about constant with the heat input canceling out the gas tank cooling as fuel was drawn off. 

If you build a gas pressure regulator for Nina then this should not be a concern. 

Gail in NM


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## xo18thfa (Aug 7, 2010)

Thanks men. It's getting there. Looking forward to doing the fuel system. Then we'll get this thing on the track.

Gail: It's surprising how touchy butane burners can get on a Gauge 1 loco. I chase ours around the track and adjust 3 or 4 times during a run. On the big main line engines they put the fuel tank in the tender tank and add warm water to take out the temperature problems. The idea of a pressure regulator is appealing


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## xo18thfa (Aug 24, 2010)

Today lets get started on the fuel system by fabricating a fuel tank. Since Nina is a gas fired locomotive, the fuel tank is a pressure vessel. So build the fuel tank in the same manner as the boiler. Before starting there are some design considerations to go thru.

The filling adapter is a valve held closed by a spring. The fuel enters the tank thru the adapter while in liquid form. Almost like pouring water into a glass. Filling adapters are commercially available or you can cannibalize one from a refillable lighter or a small torch. Adapters screw into a bushing on top of the tank. Here are three adapters I have:






The adapter on the left came from a small Harbor Freight torch (that crapped out immediately). The thread is metric M5.0 x 0.5. The center adapter came from a micro pencil torch and also has a thread of M5.0 x 0.5. The adapter on the right came from Sulphur Springs Steam Models (unfortunately out of business) and has a M4.5 x 0.5 thread. Thats the one I will use, because I have a tap for it.

The next consideration is the pressure inside the fuel tank. We need to test our tank as with the boiler to ensure it operates safely. The question is what kind of pressure are these tanks under? There are two types of fuel commonly used: 100% butane (lighter fuel or Chinese tabletop cooker fuel) or a mixture of 70% butane and 30% propane (Coleman brand camp stove fuel).

I found a chart that shows the pressure of these fuels under various temperatures:






At 110 degrees F, the 70/30 mix fuel has a pressure of 93 PSI. As with the boiler, well test the fuel tank to twice the maximum operating pressure or 186 PSI. It is interesting to note that 100% butane boils at about 32 degrees F. Below that temperature, butane stays liquid. 70/30 mix boils at about 5 degrees F. In cold weather run with 70/30 mix or the burner may not work right.

With that done, lets build the tank. Here is the drawing for the tank parts.

http://1stclass.mylargescale.com/xo18thfa/Nina%2003/Fuel%20Tank.jpg

Use the exact same techniques for the fuel tank as with the boiler. You are an expert at this, so not much more to explain. Here are the parts turned up and ready to silver solder.






And fresh out of the pickle tank.






Now for the pressure test. For the boiler we used a regular air compressor, but mine only goes to 120 PSI. My little hand water pump only goes to about 140 PSI. So for this test I used a mechanical oil pump I made for a 7.5 gauge live steamer. Here is the test set up.






Fill the pump and fuel tank with 30 weight motor oil and screw everything together. Start pumping.






At 200 PSI the oil pump bottom had a very small weep, but the fuel tank held strong.

If your pump does not reach 200 PSI, test the tank as high as you can. If you can only test to 120 PSI for example, then from the chart above you would have to use 100% butane fuel above about 85 degrees F. Or for added safety, use 100% butane all the time.

Next time well get on the fuel valve.


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## xo18thfa (Aug 27, 2010)

Well  change 1. The fuel tank I made last time is not going to work out very well. The fill adapter and gas valve are too close together, making a generally bad arrangement. So send that tank to recycle. The new fuel tank is horizontal. It is also made from 1 nominal copper pipe and is 3 long. It will have a slightly higher capacity and wont stick out quite as much. 

All the parts are the same, with two exceptions. First, the new tank requires two mounting bushings instead of one. Second, the end plates are solid. 

Without holes in the endplates, we cannot use the #8 sheet metal screw and wood block trick to secure the plates for turning. Instead soft solder a piece of brass round to the endplate blank.






And chuck the assembly in the 4-jaw for turning.

Next, find the jig you used for aligning the water gauge bushings in the vertical boiler barrel. Well need it to align the mounting bushings on the new fuel tank.






The remainder of the new fuel tank assembles and tests just as before.

With the new fuel tank done, lets switch to the fuel valve. The fuel valve is similar to the bottom end of the water gauge. Its a needle valve with the addition of a packing nut to stop gas leaks around the needle stem when the valve is open.  Heres the drawing of the major parts.

http://1stclass.mylargescale.com/xo18thfa/Nina%2003/Fuel%20Valve.jpg

The first part to make is the needle valve stem. We will use the old machine screw/rod trick to make the needle stem. Tap a #4 x 40 about 1/4" deep into a length of 1/8 stainless steel rod. Loctite a #4 machine screw.






Set the compound slide on the lathe to 5 degrees. Chuck the stainless rod and turn a 10-degree included taper for about 1/8 length. The small end of the taper should just fit into a #57 hole.






Cut the stainless rod to 1/2" length. Tap again for #4 x 40 and loctite another screw. Fashion an appropriate knob for the needle valve.






Loctite the knob and the needle valve stem is ready to go.






The fuel valve body and packing nut are silver soldered assemblies as you did for all the plumbing parts.






Silver solder the valve body parts. Chuck the fuel valve body in a chucking spigot. Drill #31 to 1/4" depth. Drill #43 and tap #4 x 40 to 1/2" depth. Finally drill #57 thru.






Drill #57 in the output side, just breaking into the passageway. Make two jam nuts. Here are the parts ready to assemble.






And the finished valve. The bottom end screws into the fuel tank. The horizontal leg is the takeoff to the burner.






Heres the new fuel tank and fuel valve. Eventually the tank gets covered up by a cab and a coal bunker maybe.






Standing on the footplate is Jennifer. Shes the company presidents niece and the new payroll clerk. Since Jennifer came on board, theres been a lot of pay problems. Most of them are imaginary, but many are for real. The guys back in the shop are spending way too much time in the front office these days. I dont know how long shell be around.

Anyway, next time well get started on the burner.


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## zeeprogrammer (Aug 27, 2010)

How many of you noticed the fuel tank first?
How many of you noticed the girl first?
'Tis the classic separator.

Nice post. Thanks.


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## Maryak (Aug 27, 2010)

zeeprogrammer  said:
			
		

> How many of you noticed the girl first?
> 'Tis the classic separator.



Girl ???.......................Surely she's NINA ;D

Best Regards
Bob


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## Deanofid (Aug 28, 2010)

Another nice job on things, Bob. Everything you've done here looks top rate.
It's like you're a machinist, or something!  

Keep up the good work, and thanks for all the pics.

Dean


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## 4156df (Aug 28, 2010)

Bob,

The engine is really looking good. Thanks for posting.

Re: Jennifer...In the words of an old supervisor of mine, "There are work horses and there are show horses. You should hire work horses."

Regards,
Dennis


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## doubletop (Aug 28, 2010)

I don't know why I've missed this post, but a fuel tank is something I've been meaning to tackle. Thanks for this, a perfect reference for me.

Pete


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## xo18thfa (Aug 29, 2010)

Thanks a lot guys for taking a look at this project and help keeping me going.

In Gauge 1 railroad modeling a lot of builders use a human figurine like "Jennifer" to gauge size and proportion. They also use the figurine in the write-up log to give it an anecdotal story affect. Makes for fun reading. So -- Jennifer -- well, she's a very nice young lady, but a real "box of rocks"

Question for Dean Williams and/or Bogstandard: On the Jerry Howell Mini-Burner, is the "Venturi" a press fit into the "Body Sleeve"?? A modified Jerry burner may go in this engine.


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## Deanofid (Aug 29, 2010)

xo18thfa  said:
			
		

> Question for Dean Williams and/or Bogstandard: On the Jerry Howell Mini-Burner, is the "Venturi" a press fit into the "Body Sleeve"?? A modified Jerry burner may go in this engine.



That's the way I made mine, Bob. The venturi tube has a small step turned onto the bottom
end, and it is just a snug fit into the body sleeve part. I just made it tight enough to be firm
when pushed in, but still can come apart if you pull hard on it, to make changing jets easy, if needed.

Dean


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## xo18thfa (Aug 30, 2010)

Deanofid  said:
			
		

> That's the way I made mine, Bob. The venturi tube has a small step turned onto the bottom
> end, and it is just a snug fit into the body sleeve part. I just made it tight enough to be firm
> when pushed in, but still can come apart if you pull hard on it, to make changing jets easy, if needed.
> 
> Dean



Thanks Dean, that's what I will do.


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## xo18thfa (Sep 3, 2010)

I am going to build two different types of burners, then have a burn off to see which works better. One burner is the standard poker type used widely in gas fired engines. The other is the blow torch type burner that Mr Glaser originally used for Cracker. Might still do the Jerry Howell Bunsen burner too, but we'll see. I dont recall seeing a blow torch burner in a Gauge 1 loco, so this will be an interesting experiment.

Lets get started by making gas jets. Gas jets are normally made with highly precision drilling machines capable of drilling the 0.006 to 0.008 holes. I dont have that kind of machine, so we will have to use a different technique.

The technique to make gas jets comes from Mr Dean Williams (Deanofid). His technique is shown on his website for the fabrication of Jerry's Bunsen burner. Here is Deans page on the Bunsen burner, and while you are at it, check out his main page. He does incredible work with a Taig lathe.

http://www.deansphotographica.com/machining/projects/burner/burner.html

Deans technique uses commercially available wrist watch bushings as the gas orifice. The bushings are the KWM German Made type available from the TimeSavers Company in Scottsdale, Arizona (http://www.clock-parts.com/index.htm). TimeSavers has two bushings that will work for our applications. The size L-01 (part number 11301) and the size L-56 (part number 11356). The idea for the gas jet is to insert a wrist watch bushing into a 2 x 56 brass model hex bolt and install in the burner.

Heres the dimensions of the wrist watch bushing.






To make a jet, start with a jig to hold the model hex bolt. Cut a 1 1/2" or so length of 1/4" brass rod and face both ends clean. Drill # 42 hole 1/16 deep. Then drill and tap 2 x 56 about 1/4" deep. Screw in 1/8 2 x 56 model hex bolt. The #42 spot drill ensures the bolt rests flat on the head.






Chuck the assembly in the 3 jaw. Lightly center drill and then drill thru with a #56 drill. Number 56 drill provides a very nice press fit for the 1.2mm diameter watch bushing.






For best results, rough drill with #57 or #58, then finish drill with #56.

Finish the bolt drilling with a very small chamfer to break the sharp corner left by the drill. Just twist a countersink bit with your fingers.

Now chuck the hex bolt and fixture in the drill press. Place a watch bushing on the drill press table with the flat face down. Lower the drill chuck, aligning the watch bushing with the hole in the hex bolt. Use a needle or long pin to move the watch bushing around. When aligned, press the watch bushing home.






Dont be intimidated by the small size of the watch bushing. Getting it aligned and pressed in is easy to do. They key is the little chamfer, it helps align the watch bushing and prevents getting hung up on the hole edge.

Now fabricate two jet bodies that will screw into the back of the burner. Make them in the same fashion as the other plumbing and gas parts. You are an expert at this. Here is the drawing:

http://1stclass.mylargescale.com/xo18thfa/Nina%2003/Jet%20Body.jpg

Here are the jet bodies ready to install. The jam nuts will give some backward/forward adjustment for the jet. 






I think these watch bearings will work great for jets. Looking forward to setting something on fire. Next time we will get the burners done.


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## xo18thfa (Sep 15, 2010)

I've been playing around with Dean William's gas jet method. They work great. I plan to order some more bushings to have a larger assortment. Only have the L-01 and L-56 sizes now. 


Today we are going to get the burners done and do an initial test to see how they do. The first burner is the blow torch burner that Mr Glaser used in the original Cracker engine. The burner consists of only two parts: the burner body and a gas defuser. I want to use Mr Glasers burner as is, so convert the dimensions from metric to inch. This is Mr Glasers drawing for the Cracker burner, with dimensions changed to inch.






The gas defuser is the difficult part to machine. It has eight equally spaced holes that fall on a pitch circle. Set up a pitch circle drilling operation, just as with the safety valve. It is not shown on the drawing, but the pitch circle diameter is 0.266. Machine the defuser shell first and then drill it out. Here is the drilling set up for the gas defuser.






Just as with the safety valve, I found it more accurate to traverse each hole from the center position. 

The burner body is a straightforward turning and drilling job. 






Ream the large hole in the burner body to accept the defuser. The reamed hole will make a nice, light push fit for the defuser.






Lastly, turn a 3/16 thick mounting ring that just fits inside the boiler flue. Blow torch type burners need more air to operate then the mixer holes provide. Drill some 5/32 holes thru the mounting plate. Silver solder the mounting plate to the burner body and tap a couple 2 x 56 for mounting screws.






The photo shows six auxiliary air holes, but four are enough.

Lets see how it does.






This burner requires a small jet. Use the L-56 watch bushing with a 0.15mm (0.0059) bore to make the jet. The L-01 bushing will not work; the burner wont light at all. With the small jet, this burner is a micro sized nuclear furnace. It burns wicked hot.

Next lets do a regular poker style, Ruby type burner. This burner is just a brass tube with slots sawed along the top. Here is the drawing:

http://1stclass.mylargescale.com/xo18thfa/Nina%2003/Poker%20Burner.jpg

There is a couple of ways to do the burner tube. You can drill out a 3/8 solid brass rod with 5/16 or use a 3/8 OD, 5/16 ID tube. I used tube, which is available from McMaster-Carr and others. There are 12 slots in the burner tube, each 0.020 wide on 7/32 intervals. The slots are wider at the rear end and get progressively narrower towards the front. Two options to cut the slots: cut them by hand with a jewelers fret saw and a very thin blade, or with a circular slotting saw on the lathe. The fret saw is easier and would work fine, but we never do anything the easy way. 

To cut the burner slots on the lathe, rig up a tubing holder from the wooden parts leftover from boring out the boiler barrel.






Mount the jig on the lathe cross slide and a 0.020 thick slotting saw blade on an arbor.






Advance and traverse the lathe carriage the required depths and intervals to make the slot cuts. They actually sell saw blade arbors for this kind of work, but I dont have one. Had to jerry-rig this arbor. It worked fine.

As with Mr Glasers burner, turn, tap and silver solder a mounting ring from 3/16 brass plate. Poker burners dont need auxiliary air holes. They draw all their air from the mixer.






Here is a test burn in open air using a larger, 0.20mm jet.






I played around with the poker burner in the boiler and discovered is worked best with a small jet. In open air, it would not light at all with a small jet. What happens inside the boiler is the important part.

I changed my mind and decided to mount the fuel tank on the fender. All the contraption stuff looks nice. Rig up a fuel line. Use a nut and cone type connector on the burner end of the fuel line. They seal very tight and handle heat better then a packing type connection.






With that, all the mechanical work for Nina is done, just cosmetics to do. Next time we will experiment with the burners, set the safety valve, re-assemble and pack all the glands. Then its ready for the first steam trial.

Getting nervous..


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## Deanofid (Sep 15, 2010)

Nice burner work, Bob. There seems to be quite a bit of opinion on how to make one, but both 
of the ones you made show how to do it with excellent results.

This thread sure has come a long way since the first post! Impressive work throughout.
Thanks!

Dean


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## xo18thfa (Sep 15, 2010)

Thanks Dean. Your technique with the wrist watch bushings absolutely saved the day. I have some commercially made jets from a Gauge 1 supplier. They are huge and clunky and require a 2BA tap. Plus I don't know what size they are. Your method gives a lot of options. The small jets works best. So easy to make.

Just got the safety valve set for 30 PSI lift using the poker burner. Works good, sputters a bit then closes.

Fuel tanks gets too warm for my liking. I will try to insulate the mounting bracket.


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## zeeprogrammer (Sep 15, 2010)

xo18thfa  said:
			
		

> Then its ready for the first steam trial.



Woo Woo! Can't wait!



			
				xo18thfa  said:
			
		

> Getting nervous..



You? Nah.

What is making the fuel tank so warm?


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## xo18thfa (Sep 18, 2010)

Hi Carl, it's gettin' there, slow but sure.

Time to start testing and fixing all the bugs. First thing to play with are the two burners plugged into the boiler to see how they behave. Leave the top boiler plugs open so steam can escape during the test. Fill the boiler about 2/3 full. Have some heavy soap water and a Q-tip handy. Hook up a burner and light it. Wipe some soap water on each gas line joint to test for leaks. If there is a leak, then the soap water will make big bubbles. Right away there was a problem. The fuel tank started to overheat. Heat radiated thru the chassis and into the tank. The fix is to insulate the fuel tank from the chassis. Do this with a strip of wood under the fuel tank and wooden washers on the mounting screws. Something like this:







That did the trick. The fuel tank stays nice and cold now. I will come up with a better fix later, maybe. Probably 20 years from now it will still look like that.

The poker burner with a small jet is the one to use. While the blow burner lights up very easy and burns hot, it does not heat this boiler very well. The flame blows thru the flue too fast and just heats up the smokebox. I will experiment more later, but for now, go with the poker. The poker burner is a little difficult to light. At first it whistles like a jet engine, very piercing irritating sound. After warming up a minute, it settles down. After a little gas burns off it works very well. Total burn time on one fill: 35 minutes.

Now start assembling the plumbing parts. Before burning any real water, make a tommy bar spanner like this:






The pins in the spanner engage the holes in the top of the safety valve and allow adjustments while keeping fingers out of the way.

Get the engine, tools and supplies ready for steam testing. Mount a large pressure gauge in the fill plug.






The large copper tube loop below the pressure gauge is called a siphon. All steam pressure gauges need a siphon. When the boiler warms up and the first steam goes into the siphon, it condenses back to water and settles in the bottom of the siphon. Water acts as a barrier between the steam and the gauge. What actually operates the gauge is compressed air. Without the siphon, wet steam goes into the gauge mechanism and eventually damages it.

Now set the safety valve. This is done with live steam pressure, not compressed air. To set the valve, take off the locking nut and open the top until the spring is loose. Plug the remaining holes in the boiler and light it up. At first a lot of water will spit out of the valve, but when everything warms up, steam will flow. Use the tommy bar to tighten the safety valve until the steam stops. Note the pressure on the gauge, if any. Let the boiler build more pressure until the safety lifts again. Keep tightening and noting the gauge pressure. Repeat the process until the safety lifts at about 30 PSI. Shut down the burner and let the pressure drop. Re-light and makes sure the safety lifts at 30 PSI. If all is well, put the lock nut on and sinch it down. Repeat the safety valve test several times to ensure it reliably lifts at 30 PSI.






This safety works very well. At 30 PSI, it sputters open/close and keeps the pressure right at 30 PSI. So far, no problems with it lifting, sticking open and draining the boiler. 

Now lets install the water gauge. Wrap teflon tape on the threads and screw into the boiler. Drop a #21 drill thru the water gauge top and adjust in/out until the bit fits nicely. 






Tighten down the jam nuts. Make sure the drill bit is till free. They jam nut method is very secure. The compress the teflon tape and make a super water tight seal. They are the way to go.

The watertight seal for the gauge glass is from rubber O-rings. I used metric O-rings with a 3mm ID and 1mm wall thickness. They stretch nicely over the 5/32 glass and inside the 1/4 x 40 packing nut. Use 2 O-rings on each end of the glass. Tighten the packing nuts only finger tight, does not need much to seal. The olden days of using graphite yard for water gauge packing are long gone. Dont waste your time, just get the rings.

Fill the boiler to about 2/3 glass, fire it up, lift the safety.

Now for another disaster. The (**bad words**) gauge did not work. Water level would not register in the glass; it was nothing but a bubble. Then, it would only blow down water, no steam and not re-fill. Maybe the top end got plugged with teflon tape or something. So I took it apart and discovered I never finished drilling out the top end. So, yes, it was plugged all right, with about 3/16 of solid brass. After drilling it out and re-installing, the water gauge worked like a champ.

Thats a great water gauge from the old master, LBSC.

We are going to quit for now, had enough. We have a mega big disaster to solve next time.


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## shred (Sep 19, 2010)

FWIW, I found that equal-depth slots worked better than decreasing ones in my Cracker's poker burner in regards to lighting the burner and keeping it lit:

http://www.homemodelenginemachinist.com/index.php?topic=2049.msg37054#msg37054

That design is a tad different than yours, but maybe worth trying if you're having lighting issues.


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## doubletop (Sep 19, 2010)

Those burners look great 

After a bit of a conversation with Shred a while back I made this poker burner. I just used a 24tpi hacksaw blade.












http://www.homemodelenginemachinist.com/index.php?topic=9111.0

Its hopeless in a confined tube though. whereas yours burns well in a tube and not outside It maybe just the size of the mixer air inlet.

BTW - how come your copper parts look so old when you are in the middle of construction? Something in the air in Vegas?

Pete


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## Blogwitch (Sep 19, 2010)

Bob,

Having just read this post, and I am not trying to be a killjoy, but for use in the UK, the rechargeable gas tank should be built slightly differently.

On the filler valve, it has a stack tube that goes down about 1/3 rd the depth of the tank. That is to make sure you won't be feeding neat fluid to the burner by allowing a chamber for gas to occupy by only being able to fill the tank 2/3 rds full.

The end caps have to be flanged and silver soldered like a normal boiler, plus have a phos bronze stay thru the middle.

I don't know how they are made or from what materials, but the takeoff valve has to be made specifically for gas use, a general purpose one would be frowned upon or maybe banned.

The major part is that in the UK, the standard pressure test for a rechargeable gas tank is to 360 psi.

BTW, the 'Ronson' filler valves are available from most boiler and steam valve suppliers in the UK, and as you quoted, they are 4.5mm fine pitch. You can usually pick up a carbon tap from the gas filler supplier for a few squid.


Bogs


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## xo18thfa (Sep 22, 2010)

Hey shred & doubletop:  The idea for reducing the slots came from experiments with the Ruby Gauge 1 steamer from Accucraft. It works in that engine, so they say. But that has a different flue diameter and length. It did not make any difference here, in fact more work then it was worth. The next burner will have equal slots and hand sawed rather then machine sawing. What did you guys use for jets in your burners? I dont know why the copper tarnishes so much. Probably my bad breath.

Hey Bogs. This is the first butane tank Ive made. I looked on the internet for guidance and standards, but did not really find any. I should have asked here on HMEM. For the stay, I looked at Kozo Hiraokas New Shay book where he lays out copper boiler calculations in great detail. According to the charts, with 1/8 thick endplates at 100 PSI, stays are 1.125 apart. This tank is only 1 ID. If the end plates were 1/16 thick, a stay is required. I determined the 200 PSI test figure based on engineering data I found for 70% butane/30% propane gas. 70/30 reaches a pressure of 93 PSI at 110 degrees F. I doubled that figure and rounded to 200 PSI. After making the tank and testing it, I did an experiment to verify. Here is the experiment I did and the results:

http://www.mylargescale.com/Community/Forums/tabid/56/aff/11/aft/117041/afv/topic/Default.aspx

I yield to expertise on this topic. If there is a standard available, I will use it. 




Lets get Nina running on the rollers. Install all the steam and exhaust piping and the throttle in preparation for the first steam run. The packing nut joints use a single 3 x 1 O-ring. The banjo fitting on the steam side uses gaskets. Cut two gaskets from brown shopping bag paper and soak them in steam oil. Brown shopping bag is the best gasket material in the world. The exhaust side does not need gaskets.

Fill up the gas tank, put more water in the boiler, and charge the lubricator. Light it up and let the safety lift. Open up the throttle and see what happens.

The first steam run was a total disaster. The engine would barely kick over on its own. It would turn a few times and stop. No power. Finally, it seized up solid and would not turn at all. I disassembled the engine. It took a pair of 12 channel lock pliers to pull the piston from the cylinder. There was a big chip brass stuck in the cylinder wall and it bound up the piston. Once that was out the piston moved freely again.

What was causing the lack of power? Somewhere in the design phase I made an arithmetic error and the piston ended up 3/32 too long. At top-dead-center the piston was just below the cylinder cover and clearly blocking the port hole. The steam opening started when the piston was about 1/3 way down, way too late. The exhaust closed way too early, probably causing compression near the top. Somehow, the engine ran fine on the air compressor. Steam from the boiler was a totally different outcome.

The fix was ugly:






Grind a big notch in the piston so the porthole is never covered. Actually, the notch in the piston works the best. The smaller volume in the cylinder at top dead center means less steam space to fill during the power stroke.  That will save on steam consumption.

And, there was another potential problem. All along I was worried that the #47 holes in the cylinder and engine standard port faces were too small. So I enlarged all three to #40 (0.098). These may still be too small, but for now, we will try them on steam.

After hooking everything back up and building steam, the engine took off like a gunshot. It ran long, strong and smooth. Heres a 16 second clip:

[ame=http://www.youtube.com/watch?v=mdq49DjHLN8]http://www.youtube.com/watch?v=mdq49DjHLN8[/ame]

The first test run lasted 24 minutes before running out of fuel. That would have been the remaining fuel after an 11 minute warm up.  On the second test I shut down the burner after the safety lifted and refilled the fuel. That run lasted 32 minutes before running out of water. I think with a full water fill, it should go 35 minutes and run out of fuel. That will be good.

The wheels turn at about 160 RPM, the engine about 680 RPM. That works out to about 1 foot per second. The throttle does not control speed very well, its basically on or off. Well see how it works on the track.

Nina will make its public debut at our next steam up on 2 Oct. Hopefully, since it runs on the rollers, it should run on the track.

There are some modifications to do before then. They include insulating the boiler from the frame, insulating the lubricator from the boiler and a little change to the burner.

Getting nervous again.


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## kustomkb (Sep 22, 2010)

Congratulations! ;D

Looks and sounds great. I look forward too seeing it heading down the tracks.


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## shred (Sep 23, 2010)

xo18thfa  said:
			
		

> Hey shred & doubletop:  The idea for reducing the slots came from experiments with the Ruby Gauge 1 steamer from Accucraft. It works in that engine, so they say. But that has a different flue diameter and length. It did not make any difference here, in fact more work then it was worth. The next burner will have equal slots and hand sawed rather then machine sawing. What did you guys use for jets in your burners?


Looking good. 

I used a jet from a JetBoil camping stove spare parts kit which I think is an 0.21mm orifice (there's a little saga of obtaining and fastening the jet over in my old build thread... short story: solder or screw in only). My first iteration had decreasing slots, but deepening them helped quite a bit. I made my burner with a removable burner tube to do some experiments with since info was very limited at the time but it turned out to work just fine after the slot deepening, so I've not messed with it since.


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## SAM in LA (Sep 23, 2010)

Bob,

Very nice. I'm looking forward to seeing a video on Nina running on tracks. Good luck.

SAM


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## zeeprogrammer (Sep 26, 2010)

Wonderful news Bob! Best of luck Oct 2nd.


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## xo18thfa (Sep 26, 2010)

Thanks a lot fellas. Nina just came out of the shop after the modifications and it's almost ready to go. Last thing I have to make is a new steam pipe from the lubricator down to the motor. After all the insulation, the current pipe is too short.

Gettin' nervous.


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## xo18thfa (Oct 2, 2010)

Before heading out the track, we need to do a few important modifications. The first two are critical, the others are optional.

The first modification is to the burner. The original mounting collar places the burner in the middle of the flue. This is no good. There is not enough space at the top for the burner to operate correctly. Chuck the burner assembly in the 3-jaw and turn the mounting collar off. Fabricate and solder a new collar that sets the burner as low in the flue as possible.






Next insulate the boiler from the chassis. Use some 1/8 thick strips of wood under the boiler barrel and smokebox. Use a strip of wood under the footplate as a washer, so the boiler mounting screws dont transfer heat:






These fixes make a big difference. The burner is much easier to light. It pops on right away. Now you can crank the gas valve wide open and really get the burner going. Before, too much gas would blow the fire out.  The run time on the fuel tank drops to about 25 minutes, but the increased fuel make the boiler steam much better. The insulation keeps the chassis cool to the touch. You can hold the engine in your bare hands for an entire run.

The next fix is on the drive chain between the axles. Ladder chain stretches. There is a worry that the chain could hang up in a switch and derail the engine. Remove the lower center frame stretcher and fabricate a little chain hanger from a section of smooth copper pipe and bend brass strip. Soft solder or screw the assembly to the stretcher:






That should keep the chain from dragging in the sleepers. While you are in there, change out the machine screws with some model hex head bolts.






The last thing is to make an air choke for the burner. Its a collar with a 1/4" hole drilled crosswise to match the mixer holes on the burner. Silver solder a threaded stud to accept a 2 x 56 locking grub. Make a sexy wooden handle so the fingers dont get burned.






At first I thought the choke would be a cute, but un-necessary gadget. It turns out to be very handy. The choke takes out the annoying whistle and jet engine sound while the fuel tank burns down and the boiler warms up. While running, open up the air and get the burner rocking.



Now for the debut run. Service the engine in the usual fashion. Lubricate all bearing surfaces. Put about 5ml real steam oil in the lubricator. Fill the boiler to the very top with fresh distilled water. Withdraw about 45ml. It will appear as a full glass on the water gauge. Close the throttle. Charge the fuel tank and light up. After about 9 minutes, shell be ready to go. Set switches on the track for the mainline and wait for a green light from dispatch. Open the throttle about 1/2 to 2/3. As you look at the flywheel, give it a spin clockwise, top of the flywheel going to the rear of the engine. Get out of the way or get run over.

[ame=http://www.youtube.com/watch?v=PAekprR0vC0]http://www.youtube.com/watch?v=PAekprR0vC0[/ame]

[ame=http://www.youtube.com/watch?v=RF7aUdJu1Zk]http://www.youtube.com/watch?v=RF7aUdJu1Zk[/ame]

[ame=http://www.youtube.com/watch?v=tVqctcoKqAg]http://www.youtube.com/watch?v=tVqctcoKqAg[/ame]

[ame=http://www.youtube.com/watch?v=IUpRyRIFGvc]http://www.youtube.com/watch?v=IUpRyRIFGvc[/ame]

[ame=http://www.youtube.com/watch?v=hIWnKAsuFX0]http://www.youtube.com/watch?v=hIWnKAsuFX0[/ame]

It took 2 runs to learn how to run it and understand the quirks. After the learning curve Nina ran strong and smooth. Its a real messy engine at the start. Lots of water and oil splatter, but calms down quickly. I did not time it, but the run times were about 15 to 17 minutes without refilling the tank. It ran out of fuel before running out of water.

Overall, a great run day. Im happy.

Next time, we will work on a cab, some finishing details, paint and wrap this project up.


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## shred (Oct 2, 2010)

Thats' awesome. It's so much fun when a live steamer comes to life :bow:  woohoo1 Thm:


FWIW, I tried rotating my burner (offset in the flue, but not so much) so the flame aims 'downward' on the advice of some Gauge 1 types, but it didn't seem to make much difference.


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## ozzie46 (Oct 2, 2010)

WAY TO GO!!! :bow: :bow: :bow: :bow:
 It sounded real good too. Can't wait to see it with the cab and paint job.

  Ron


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## GailInNM (Oct 2, 2010)

And a train to boot on a shakedown run. Running strong and smooth.  Thm: Thm:
woohoo1
Gail in NM


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## bearcar1 (Oct 2, 2010)

Oh that is so very cool XO! Such a beautiful sight and sound to see making its way grandly down the sidings. Truly a fine build as well. Thm: Thm:

BC1
Jim


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## joe d (Oct 2, 2010)

Way to go Bob!

I've been following along with great enjoyment from the start, have filed away a lot excellent tips, and I'm really happy on your behalf
for what must have been a really great day at the track.

Can't wait to see her all done up with a cab and a flash paint scheme Thm: Thm:

cheers, Joe


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## zeeprogrammer (Oct 3, 2010)

Awesome. That had to feel good.
Congratulations on a great run.
Looking forward to the finish.
Don't be playing with it too much. You know what they say. ;D


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## kcmillin (Oct 3, 2010)

CONGRATULATIONS!!! 

That is a fine machine you built there. She has some torque I see, and runs real smooth down the tracks. I like it, and you must be very proud indeed.

Well Done Thm:

Kel


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## putputman (Oct 3, 2010)

That is so neat. :big: :big: :big:
Runs so smooth and appears to have enough power to pull a fair size load.


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## Maryak (Oct 4, 2010)

Wow,

That's fantastic :bow: :bow: :bow:

I played it yesterday but no sound. Found the drivers for my sound card and Yep played it again and again. ;D ;D I especially like the sound when she's pulling the rolling stock.

Best Regards
Bob


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## SAM in LA (Oct 4, 2010)

Bob,

I just saw your videos and Nina looks good and runs like a scalded cat. Maybe you can start a locomotive drag racing club.

I'm looking forward to seeing what Nina has in store for us next.

SAM


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## xo18thfa (Oct 5, 2010)

Thanks a lot guys for all the kind words. It felt really good seeing Nina running around the track. Our club track has two difficult grades, not so much steep as they are long. It plowed along with out missing a beat. The videos make it look like it runs fast, but it's a slow engine.

There is still a lot to learn about running it. It's a different thing to run on track, then to run on test rollers. 

Next is some appropriate rolling stock. Probably 4 wheeled gondola like those, but larger for scale appearance.

Thanks again. Bob


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## kustomkb (Oct 5, 2010)

Great Job!

I especially liked the head on shots.  ;D ;D


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## Deanofid (Oct 6, 2010)

Ahh, what a sweet runner, Bob! I think it's great, and goes along at just the right speed.
I could watch Nina run for a long time. How neat!

Dean


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## arnoldb (Oct 6, 2010)

Good going Bob; great job Thm:

It's good to see a loco run at a more scale-like speed than hell-for-leather. Like you said, these small locos can be quirky and takes some getting used to; I'm still trying to figure out how to make my Idris replica run more sedately; it comes down to a little "mistake" I made with the regulator by equipping it with a round wheel that makes for less control, and maybe the fact that I haven't finished a proper track layout to run it on with a couple of wagons in tow...

Kind regards, Arnold


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## xo18thfa (Nov 28, 2010)

I have not forgotten the Nina project. Its just been getting run hard over the past 2 months. Theres been a bit of a learning curve to running the engine, but Ive got it down now. A run lasts 25 to 27 minutes and gets 12+ laps on our clubs 300-foot mainline track. After building pressure, I shut down the burner and refill the fuel tank. The air choke on the burner is a very big help. It does a good job adjusting the air so the burner runs silent. Now that the motor is broke in and running very smooth, there is a lot more response in the throttle. "Company notch" (half throttle) on long straights and full throttle on curves and grades. No sitting back munching on a cheeseburger, you have to follow this baby and drive it.

Yesterday was a steam up and Nina got three long strong runs. On the 3rd run the engine had a catastrophic derail on a bridge and crashed hard to the ground. The crew escaped injury. The fire stayed lit, so I set it back on the track and finished the run. No damage other then a bent smoke stack.







I dont like the new aerodynamic look, so that will get repaired.

Yesterday was quite humid in the morning, so the steam plumes were gorgeous. 

I am thinking about placing an order to clock parts supplier for some more watch bearing. Get the next 2 or 3 sizes up and experiment more with the burner.

Nina is going in to the shop next week for repairs, cosmetics and paint. Next steam run is 8 Jan. Baby should be in news shoes by then.


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## arnoldb (Nov 29, 2010)

Rotten luck on the derailment Bob... But then that will happen on live steamers!
I'm really looking forward to see Nina all fixed up and painted !

Regards, Arnold


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## cl350rr (Nov 29, 2010)

Unbelievable! I was just reading through your build thread on My Large Scale for the 5th or 6th time, dropped by here and there you are... 

Just wanted to thank you for posting all of the building techniques. I used the strap building method from your oiler this weekend to make a fuel tank mount (I have been struggling for a design for a while). Not as clean as yours but resulted in a presentable mount.

great thread and a sweet looking engine. can't wait to see it finished.

Randy


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## doubletop (Dec 11, 2010)

Bob

Well done!!! Don't know where I was on your great day, but I missed your post. I was probably head down sorting out my loco. Doesn't it fell good when it all comes together. 

Pete


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## zeeprogrammer (Dec 11, 2010)

Looking forward to the new shoes! Video too please!


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## xo18thfa (Feb 17, 2011)

Thanks for the comments men. Randy: I just found your Hit-n-miss project. Very nice. Looks like the bands worked out perfectly.

Took Nina off line last week to finally get it finished up. After a few months of successful running, its time to get this project wrapped up and move on to the next. 

First thing to do is change out the front buffer; its not the correct type. Nina is more along the lines of a Walsh mining loco, so it needs a chain and hook style front coupler/buffer. Even tho the front coupler will not get used, it still needs to look the part. The link and pin coupler on the back will stay.

The front coupler parts are from 1/16 steel plate, 1/2" square tubing and a small eyelet. Saw, grind and file everything to shape. Whatever shapes and styles you like.






The coupler parts are held together with a single #2 x 56 screw and soft soldered together. Sweat off the old coupler. Drill for some #2 x 56 model hex head bolts and bolt to the front pilot frame. 






That looks a lot better.

Next is a decorative brass band to go around the horizontal boiler shell. There are no other decorations on this engine, so we need to have something for the crew to polish. I am thinking about painting the boiler gloss black, with a flat black smokebox. The brass band will separate the two colors. Fabricate the band in the same manner as the bands used on the lubricator.






The water gauge lower end needs a drain tube for the blow down. Right now it just blows down on to the footplate and makes a mess. Fabricate a drain tube from 3/32 OD, 1/16 ID tube. Use 1/4" hex brass to make the #10 x 32 union nut. Run the drain either thru the footplate or out the side. After all the plumbing done so far, this job is a snap.






The gas and drain plumbing looks Rube Goldberg, but the cab will cover up most of it. 

Now for the cab. Ninas cab very loosely follows Welsh narrow gauge practice. It is a wooden cab, open top, opening out to the rear. The strategy is to laminate decorative wooden strips over a shell of model aircraft plywood. Installation is with #2 x 56 machine screws thru the footplate.

The decorative wood for Ninas cab is Cocobolo. Cocobolo is a tropical hardwood from Central America, similar to Rosewood. Fresh cut it is darker brown in color, but over time turns even darker. This 1/16 thick piece I have was cut 20 years ago and is nearly black now. Almost looks like ebony.

Tropical hardwoods are absolutely gorgeous and well worth the extra work to finish them. Most tropical hardwoods contain a lot of oil. Before gluing, completely wipe down the surface of the wood with alcohol or lacquer thinner to clean off the oil. Glue immediately with Titebond III. Other glues are chemically different and may not work.

Finnish the decorative wood before cutting up. Its a lot easier to finish one big piece then a zillion little ones. 

Cocobolo is so hard you can use the same techniques as brass polishing to get it shiny as glass. Sand to 1500 grit, polish with pumice and water, rottenstone and oil next and finish up with Brasso. Get out the supplies and make with the elbow grease. 400 grit sanding makes a nice finish, or you can go all the way.






Fine sawdust from Cocobolo is toxic. If you breathe it in, it will feel like a red-hot knife going down your throat. Wear a good mask, and open the windows.

Cut strips and glue to the model aircraft plywood to form the sides.






Cut some poplar strips for corner gussets and attachment gussets along the bottom.






Glue some plywood panels on the front and back. Glue stripwood over that.






Miter cut some stripwood for caps on the top and bottom.






Take a very very light skim cut on the table saw or disk sander to true the bottom edge of the cab. Paint the interior flat black. Drill some holes along the bottom gusset for #2 x 56 machine to attach the cab to the footplate.

Finish the cab with a furniture oil rub down. Shellac, varnish and poly-urethane do not work on tropical hardwoods. Too much oil in the wood. They will just peal off in a few weeks.






Set the cab on the footplate for a prelim look.






Looks pretty good. The camera does not do justice to the Cocobolo wood. It is gorgeous.

Thats it for now. Next time the engine gets blown apart for paint and final wrap up.


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## bearcar1 (Feb 17, 2011)

Nice to see "NINA" back gracing these pages again, Bob. How well does he Titebond III hold up over time? Especially exposed to such harsh conditions as steam, heat, and oil. Great looking cab sides.

BC1
Jim


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## xo18thfa (Feb 21, 2011)

Thanks Jim: I believe Titebond III is a different chemical make up then the others. It should hold up OK. I know from experience that taking apart Titebond II by soaking in water is a real chore.

Before disassembly the engine for paint, I had to fix the bent smokestack from the fall. A few bashes with a mallet fixed that. It looks better.

Time to disassemble the engine for final cleaning and painting. I clean everything first in lacquer thinner then hot soapy water. Don't know if two cleaning steps really matter. Its just a habit. 

I really hate painting. I just want this part over. Get all the machined surfaces masked with tape and attach some means to hold the parts while painting. I just painted everything with Rust-o-leum rattle can paint. Red Oxide primer to start off.






The original intent was gloss black with flat black smoke box. It quickly became evident that gloss black would look too toy like. So everything went flat black. The end sills and couplers got dark red with a coat of flat clear.






Next is getting on the brass and copper. By now everything is really tarnished and has discoloration from silver soldering. Run everything over the buffing wheel with some fine rouge compound. That will get it most of the way there. Get out the Brasso and have at it. Its a lot of work, but certainly worth the effort.






Re-assemble everything and attach the cab. And with that Nina is all done.


























The boiler steams fine. The lubricator does the job. The safety valve is very reliable. The water gauge works perfectly and blows down just right for an accurate reading. The throttle is a good design too. The burner works OK. I am going to experiment with some different jets. I ordered some 0.25mm and 0.30mm watch bearings and will them a try.

Looking back at it, the only thing I would do different build a double acting motor. While the single works fine, a double would just be better. The way the engine is set up, changing out the cylinder would not be difficult to do. Redesign the engine standard and cylinder. Use the existing crankshaft and modify the steam pipe. I would also make the rear foot plate and cab about 1/2" or more wider. The back looks too narrow.

Thanks for all the kind comments, words of encouragement and those who stopped by for a look along the way. 

Thanks and take care, Bob


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## doubletop (Feb 21, 2011)

Nice one Bob!! the coat of paint has transformed it.

I've just done a quick flick back through the posts and there's a lot of useful information in here for anybody doing a gas fired boiler for any small engine, or another loco like this.

Hopefully its not destined for the display cabinet? It just needs the vid of it running in its pristine condition to top this off. 

Pete


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