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

[xo18thfa]

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.

 

[Deanofid]

It's looking really good, Bob.

Dean

 

[ozzie46]

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

Ron

 

[xo18thfa]

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.

 

[4156df]

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

 

[zeeprogrammer]

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.

 

[ozzie46]

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

Just my 2 cents.

Ron

 

[xo18thfa]

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.

 

[zeeprogrammer]

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.

 

[xo18thfa]

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.

 

[zeeprogrammer]

Nice post! Very glad the fix worked.

 

[xo18thfa]

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.

 

[xo18thfa]

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.

 

[xo18thfa]

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.

 

[zeeprogrammer]

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?

 

[xo18thfa]

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?

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.

 

[xo18thfa]

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.

 

[arnoldb]

Bob, that is really coming along well ! Thm:

Regards, Arnold

 

[xo18thfa]

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.

 

[4156df]

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