# My First Build - The EZ engine



## njl (Apr 16, 2010)

Hi All,

Well today I finally managed to find some shop time to make a start on my first build. I decided to give the EZ engine a go, given that it is a project aimed at the first timer I hope it is just the ticket for me.

I'm sort of used to metric and imperial measurements, but my brain visualizes sizes in imperial. My mill is imperial so I have been buying imperial cutters for it, my lathe has both on it's dials and all my drills, taps and dies are all metric. Hence I have decided that my build will have imperial dimensions except for all the holes. This may sound odd but it works for me. 

So both set of plans have been down loaded. My first job was to take the imperial decimal dimesions and convert them to imperial fractions so I could measure the sizes of the parts with my ruler. I knocked up a spread sheet of all the 1/64th - 64/64th factors to decimal. My rule has up to 64ths on the scale but that is a challenge for my eyes. Maybe you guys have a way to layout in imperial decimal but I would have to use the mill table and wind the dials to do that?

Anyway here is a selection of metal stock that I am going to use. Steel for the frame, cylinder and valve case. Brass for the piston and valve and ali for the flywheel.







The first job was to cut the frame, cylinder and valve blocks from the stock






The band saw does a reasonable job but I need to clean up the cut edges in the mill and bring the parts down to size.






I'd just got the base plates set up on the mill when our holiday guests returned to our Loft House holiday apartment which is situated directly above the workshop so I had to call a halt for todays operations, so as not to inflict my machining noises on them, that wouldn't be fair.

The build will progress slowly but I hope steadily, I feel good to have finally made a start, more later.

Nick


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## 4156df (Apr 16, 2010)

Nick,
Thanks for taking the time to share your build with us. I'm looking forward to watching.
Dennis


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## arnoldb (Apr 16, 2010)

Nick, you took one of the important steps; that is to start ;D

You will find a rule for marking out a bit inaccurate, and while it should be usable for the EZ engine, maybe you must give some thought to getting a digital caliper. I see you live in the UK; you'll find the cheap Asian imports are very affordable - and the digital readout is nice and big to read 

Good luck with your project!

Kind regards, Arnold


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## Swarf Rat (Apr 16, 2010)

Great start. I'm interested in watching your progress.


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## Deanofid (Apr 16, 2010)

Good start, Nick! Keep us posted. Most of us are pretty interested in first builds, since we remember it well. 

Have some fun. We're in your corner.

Dean


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## trey3670 (Apr 17, 2010)

some of us are looking to learn from your first build to start ours!


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## njl (Apr 17, 2010)

Thanks for all the kind words, I'll share with you the things that I learn along the way, I've got a lot to learn and I'm already learning , Arnold has already triggered a light bulb in my head. 

As it happens I do have some digital calipers but had been using them pretty much exclusively to measure the diameter of parts I make on the lathe. I've already found them very useful for that and I have also noticed that when doing inside measurements the size of the hole might be just a tad bigger than the reading as the edge of the jaws can fowl on the wall of the bush so they can't expand fully to the exact size of the hole (Bare this in mind when making interference fits.)

It never occurred to me that I could also use them when laying out measurements, it is so obvious I could kick myself! Thanks again for the tip Arnold.

Nick


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## black85vette (Apr 17, 2010)

Great! Thanks for posting. Be sure you have the plans with the upload dated in November as the older upload had a couple of dimensions wrong on the upright of the frame. 

Does not hurt to layout and visually confirm that all holes line up with the other parts BEFORE drilling. ;D Saves some agravation and scrap creation.

There have been about 5 or 6 of these posted on the board so there are plenty of pictures and posts about them. Still feel free to ask questions if something is not clear.

Have fun!


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## mklotz (Apr 17, 2010)

> ...I have also noticed that when doing inside measurements the size of the hole might be just a tad bigger than the reading...



Examine the inside jaws of your calipers closely. They probably have a tiny flat on the measuring surface. This means that they are actually measuring the distance between two chords of the hole, a distance that will always be less than the actual diameter of the hole.

In general, calipers are not useful for precision measurement of holes. Use expanding ball gauges or telescoping gauges.


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## njl (Apr 17, 2010)

Black85vette - Thanks for the heads up on the plans version. I think I have the right set but will double check before drilling. I have seen the other EZ threads too so have some idea of what I should end up with! 

Yep Marv your spot on, that is exactly what happens with my calipers.

Well I made a bit more progress on the build today. The first step was to clean up the parts I cut yesterday.

This is how the parts ended up after I milled them.






All went to plan without any drama and I am pleased with the result but for anyone about to start using the mill for the first time here are a few things I learnt when I milled my first job (smoked my first cutter) making Tee nuts to hold my vice to the table.

1) Make sure the tool is turning the right way. On my machine the back gear reverses the direction of rotation so you need to switch the motor direction depending on the high/low speeds.
2) Make sure it is not going too fast I found out that turns the cutter straw and then blue.
3) Lock the axis which is not supposed to be moving.
4) Don't try and plunge end mills.

Meanwhile back at the build it was time to mark out where the holes are going to be drilled. For this step I used blue layout fluid. I'd never tried it before but it worked a treat. Just put a few drops on the part and wipe it over with a paper towel to spread it out.

Thanks to Arnold's tip I then used my calipers to scribe the lines. I worked a treat.
Here is a pic of the frame marked up.






It looks better in real life than on the photo. It is very easy to make a scratch marks and hardly needs any pressure on the caliper jaws.

Next I used an automatic center punch to pop the hole positions. I found that getting the pop spot on was more difficult than I expected. Here is the result 






I'm not entirely happy with this its very close but not perfect. Close enough I think but as the school report used to say needs to try harder next time!

Unfortunately my shop time was up and I had to get back to the gardening, the only consolations are; it was a smashing day here weatherwise and I get a chance to double check that the plans are correct before I make any holes.

Tomorrow I'm RC flying all day so doubt I'll get any more done until later in the week.

Nick


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## arnoldb (Apr 18, 2010)

Good progress Nick 

And thank you for the mention; I'm happy if I can help someone.

Kind regards, Arnold


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## njl (Apr 18, 2010)

Marv,

I just had some more thought about using my calipers for the hole size measuring. As I don't have any ball gauges yet I reckon this formula might work. 

If I take 2*(square root ( (0.5*cord) ^ 2) + (0.5*caliper reading) ^2 )) I should get the diameter of the hole.

Where the cord = the caliper jaw width.

In practise it might be a bit of a kludge but it should get me closer than my current "the reading + a tad" method!


Nick


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## mklotz (Apr 18, 2010)

Nick,

Your formula is mathematically correct but I don't believe that you can determine the "chord" value accurately enough to get good results. Furthermore, what you're suggesting relies on getting the calipers exactly on a diameter - something that's not easy to do.

Calipers are not the appropriate tools to measure hole diameters accurately. The generally accepted techniques go something like this...

diameter <= 0.25"
	pin gages

diameter 0.25 - 1"
	pin gages
	ball/telescoping gages
	inside micrometer

diameter > 1"
	telescoping gage
	inside micrometer

There is some overlap, of course, but that's a good guideline.

One can spend a lot of money buying tools to measure holes. For someone starting out, I would recommend that you buy some ball and telescoping gages first, then graduate later to an inexpensive import inside micrometer.

Edit...

One can make surprisingly accurate measurements of a bore with nothing more than a stick with rounded ends and a micrometer. Download RATTLE.ZIP from my page and read how the old-timers did it. It's a useful technique to add to your arsenal.


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## njl (Apr 18, 2010)

Thanks for the advice Marv. I've added Ball + Telescopic gauges to the tools wish list! 

Most of the critical holes I have made up till now lie in .5" - 1.5" range. As soon as folks learn you have some machine tools, little repair jobs come your way. I had a nice job to do a while back on a Westwood lawnmower where the belt to the grass sweeper had to turn through 90 degrees to feed the drive from the middle of the machine to the axel of the sweeper brush. The part was basically a shaft with two pulleys sided by side but it was also an adjustable tensioner for the belt, allowing the axel to slid in and out on three bolts, one in each end of the axel and one long bolt right through the middle of the shaft, like a tee shape. The old part had warn very badly, one of the phosphor bronze bush had completely gone and made a right old mess of the pulley and the axel. I opened up the hole in the pulley to get a nice clean parallel hole and then made up a new thicker phosphor bronze bush which I managed to shrunk fit into the blow lamp heated pulley. Swmbo still doesn't know that I had this lump of metal sitting under the frozen peas in the freezer! (but I did put it in a plastic bag!) I then made up a new axel assemble to hold both the pulleys and provide the tension adjustment and the mower was as good as new. Doing that job was how I found out first hand that my calipers were not good for measuring the hole diameter.

Anyway glad my maths was OK. I was driving out to our flying field this morning and my brain was buzzing with, "if you know the cord length and the distance between them you should be able to work it out".

Nick


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## Deanofid (Apr 18, 2010)

You're doing well, Nick. I think things are looking just dandy.



> 4) Don't try and plunge end mills.



You can, with the proper end mill.  Don't know your country, and they're called different things in different places. In the U.S., center cutting end mills are made for plunge cutting. I think it's called a slot drill in G.B. Elsewhere, ask a local machinist, or look at the end of the mill. If it's meant to plunge, at least two of the edges on the end will meet in the middle of the diameter of the tool.

Keep it up. Hope you had a good flying day.

Dean


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## njl (Apr 19, 2010)

Thanks Deanofid, must be a terminology thing.

Yep over here (in the UK) we seem to have end mills which don't plunge and slot drills which do. Typically size for size, end mills have more flutes and give a better finish, well in my (very) limited experience that's what I have found to be the case anyway. (I've only got a handful of cutters)

Yep flying was great, it's a Sunday ritual for me. I must get my flying fix or I get bad withdrawl. Hope to get some more done on the build today, metal working is becoming very addictive too. Will post back later with some more build progress.

Nick


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## njl (Apr 19, 2010)

Right oh, here is a bit more progress from today. I manged to pop into the workshop for five mins and blow me down 2.5 hours later I had made the frame.

Glad to say I had the latest version of the plans and all the holes measurements were fine.

First off I moved a couple of pop marks slightly, re-punching at an angle towards where I wanted them to go. This worked very well, I was quite surprised that it did. Then it was time to drill them. I do have a drill press but decided to use my mill to do the work as it has a vice and I can use the dials to move the drill to the precise spot I want to drill.

Here is a snap of the main face of the frame just about finished.






Next job was to tap the M3 holes. I have seen lots of different ideas on how to make sure the tap runs straight, this is how I do it.






The chuck is just resting over the end of the tap handle and serves as a support and guide. 

All holes tapped OK but I did have a spot of drama with the cutting fluid. I had a new bottle which was very full. I was just dipping the tap into the neck of the bottle each time I started a new hole on the last hole the tap fell out of the tap handle and into the bottle. So now I had to get it out, well I put the cap back on the bottle, turned it upside down, held the magnetic base of my dial indicator on the cap, turned the bottle upright again and carefully unscrewed the cap and hey presto it was dangling from the cap oiled up and ready to use! My tap handle has quite a coarse thread and it is very easy to twist it slightly when holding small taps.

Here is a shot of the tapped holes.






Once I'd completed the other faces it was moment of truth time. Would the base fit on the frame or would I have to open up the holes and make some wiggle room. Well much to my surprise it fitted without any further adjustment. 

So here is a pic of the finished frame.






The screws are just some I had to hand to show the fit and are too long to screw fully home. I've not decided yet if I'm going to use countersunk heads or maybe add some decorative feet and go with cap head bolts. I use these cap head type bolts a lot for model planes.

Well that's all for today. Next I'll start on the cylinder block. I'm thinking I will use the 4 jaw chuck for this in the lathe. It will be the first time that I have used it in an offset (non centered) type mode. I don't have any reamers so my thinking here is drill to near size and then use the boring bar to get a nice round hole. Does that sound like a good plan?

I've already had a play with the four jaw armed with Marv's set up guide when I made some extra 1/4 inch square top bolts for my lathe's Dixon tool post. Thanks Marv, I found it very useful.

Nick


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## Deanofid (Apr 19, 2010)

Hi Nick;



> I don't have any reamers so my thinking here is drill to near size and then use the boring bar to get a nice round hole. Does that sound like a good plan?



Yep, that's a good plan. It's how many of us do it if a suitable reamer isn't available. Just take the last few cuts very light, meaning about .001" when you get down to the last few thou to meet your diameter requirement, and then try a couple of passes without putting on any more cut. It'll clean up a bit even without adjusting more on for a cut, and will make a nice straight bore. 

Then make the piston to fit the bore.

You're on your way. The frame looks good!

Dean


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## njl (Apr 20, 2010)

Thanks Marv for pointing me to the rattle.zip archive. I down loaded it and had a read of the text. I think I get the gist of what your trying to do but I have a couple of question which I'm not sure about. Firstly when you put the stick across the bore how do you ensure it is a right angles to the bore. Secondly once you have narrowed the space to just the rattle room. How do you measure it. IE. how to do you measure the size of the rattle?

Thanks Dean for your info on making the cylinder, glad I'm on the right track. BTW I had a look at your website you have some nice very projects on there. Great photos too and the finish you get on your parts looks brilliant.

Well a bit more progress today but I spent most of my time trying to set up the part ready to machine. I'll show you how/what I did to set up for an off centre hole but would welcome comments on how you would do it if you have a different/better method. 

First off I marked out the stock with blue marker, scribed and center punched it.

Then I set up the lathe like so






Then I spent quite a long while trying to get the center dot to line up with the point of the center. 

This picture shows the outcome I drilled the hole with a small centre drill






It is on my scribed marks, (Ignore the milling mark just above it.) But I found it very difficult to see that it was in the right place. In the end I decided to give it a try and it came out OK. But getting my eye into the right place was very difficult. I used a 10 x Lupe but as I can't get to see all around the hole very easily and at that mag the pop hole looks a bit ragged anyway. The lathe tailstock is in the way and the cross slide blocks the bottom of the chuck. So all in all I found it was not easy thing to set up.






Here is my pilot hole






Finally I'm ready to drill out the hole ready for me to bore it to final size. I'm using the tape as a simple depth gauge. 

My method worked but is there a better way to do this off centre type of a set up?

Nick


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## mklotz (Apr 20, 2010)

> My method worked but is there a better way to do this off centre type of a set up?



What you need is a "pump center". Here's a thread where I show mine in use...

http://www.homemodelenginemachinist.com/index.php?topic=3859.msg39487#msg39487

but use the search function and you'll find other references to it.


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## njl (Apr 21, 2010)

Cheers Marv, that's brilliant, I can see that a pump center would make life so much easier. I found more examples with the search. I'll knock one of these up before I do the next offset hole. I took so much time yesterday faffing about with the set up I didn't get much further along. I was almost embarrassed to show what little progress I'd made but I was sure there would be a better way to do it.

Nick


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## njl (Apr 21, 2010)

Finished the cylinder off today.

First job was to open up the pilot hole with a 10mm drill this gives me enough clearance to get a boring bar into the hole. Any tips for tooling for boring in small holes much appreciated?

Here is the finish of the drilled hole







Here we are about to start the boring process. This miniature boring bar comes from Chronos Ltd it's made by Glanze, its 5.5mm. It needs plenty of packing up to fit into my Dixon tool holders, only the first two bolts grip on it. 






Being so small it is a bit springy. So it needs a few passes without adjusting the cut to reach the final size. This can make holes go bigger than expected if you wind in cuts without taking out the spring before measuring the diameter. Just to right of the frame and slightly out of focus you can see an example of the square top bolts I made to replace those missing from my tool post. (My first use of a 4 jaw chuck, not this big one as they are too small for it to grip).

Here is the finished bore, the finish is much improved from the drill, I hope it will be good enough. I used the auto feed to keep the tool moving at a constant rate. Stopped the lathe when the tool was full inserted to change the direction of the feed and then cut the other way backing out the tool at the same cut. I don't have any tiny HSS boring tools yet and these would probably get a better finish. I find that with these insert tools that too slow a feed gives a poor finish on steel. I put neat cutting oil in the hole too, this improves the finish.






Finally I finished off the part drilling the two fixing holes and the air hole. 






I was really pleased to find that all it fitted. And that blowing air into the hole it expells through the cylinder. Those two old battered 3mm screws are pressed into action again to test fit the part. I thought I had done a great job but then when I picked up the stock from the bench to make the valve I realized I'd gone and drilled the cylinder into the (slightly longer) stock piece meant for the valve. Not a big deal it won't affect the engine but I'm annoyed with my self for going off piste! Measure twice and all that, add note to self "check your marking up the right bit of metal too".

I think I'll make the piston next, it was so nice pottering in the workshop playing with the lathe today. Starting to look a bit like an engine now!

Nick


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## Swarf Rat (Apr 21, 2010)

Its coming along nicely. Why is it that we can do our best work in the wrong chunk of metal????


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## Deanofid (Apr 21, 2010)

I think you're coming along just fine, Nick. The bore in the cylinder looks good in the pic.



> Any tips for tooling for boring in small holes much appreciated?



You can grind them up from HSS blanks without much trouble. It's what I use for very small holes.






This one is from a 3/16" square HSS bit, and will go into holes down to about .150" diameter.
Here's a closer shot of the tip. It's about ready for a touch up on the stone, but you can get the idea:






Another good source for small boring bars is HSS end mills. If you lay a 2 flute on the table and roll it until the wide end of one flute is facing straight up at you, you can easily imagine it being the end of a small boring bar. Grind away some of the other flute so it fits in your hole, and a little off the flute behind what will be the cutting end so it doesn't rub the edge of the hole, and you've got it. Sorry, I don't have a pic handy for one of those.

Dean


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## njl (Apr 22, 2010)

Thanks for the moral support Swarf Rat, you've been there and done that too then, glad I'm not the only one!

Thanks Dean for boring bar info, great reference pics, I'll use them to have to have a go at grinding up some of my own. Yep I think I understand what you mean about grinding an old two flute endmill.

Well today I switched my focus to the piston. Here are some photos and a bit of dialogue as to how I went about making it.

The first job was turn down a piece of stock to just a fraction too big. As I don't have any decent way to measure the inside of holes accurately yet. I cut a small shamfer on the leading edge until the stock would just locate into the bore. This gave me a good guide as to how deep a cut would be to small. 

Here is a photo to show the idea.






Infact in this shot I have already cut some of the shamfer away.
I then crept down on the bore dia a tho at a time until I could do this with the cylinder.






Once I had the size of the piston it was a simple job to machine the end down for the connecting rod to go on to.

Here is a shot of the piston with the lathe tasks completed.






and here is shot of the piston sitting in the bore, its a bit dark but quite I like the effect.






The fit is pretty good I can feel the vacuum and pressure if I block the air hole and move the piston. With the air hole blocked the piston will only fall into the block very slowly. So I reckon this should be good to go. Just got to machine the conrod connection and it is done.

I also started to cut a replacement piece of stock for the valve part but a short way into the cut I heard a contactor drop out and the saw stopped. I've not worked out why yet and I haven't managed to get it going again. I've checked all the fuses and nothing has blown. I've pressed every thing that looks like a mechanical trip but it is still not playing ball. Will have to give it a good checkover and if it doesn't go tomorrow I might even have to go back to the old manual hacksaw! It did this on me once before and then the next day was a right as rain again so maybe there is something loose in the wiring somewhere. The blade grinder still works OK so it is not suffering a total power loss.

Nick


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## njl (Apr 23, 2010)

Good news. My saw, which is a DoAll bandsaw (A piccy in my welcome thread if your interested), a three phase mains jobby which weighs loads and stands taller than me, with a tiny blade with teeth rather like a junior hacksaw, is back in the land of the living. Maybe it has got some sort of an automatic thermal/overload trip out and I was pushing it too hard? Given the size of the thing I wouldn't have thought so but hey it's going again now, so parts production can continue, yipee 

Nick


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## arnoldb (Apr 23, 2010)

Good going Nick  - some steady progress Thm:
Don't let the little hiccoughs with machinery put you down ;D

As an aside though; it sounds like you have a fairly substantial saw, and it should not be quitting on you with small cuts like this. Give it a good look-over, and try to find out why it's stopping on you. Something appears to be wrong, and "wrong" things can cause damage - directly or inadvertently.

Regards, Arnold


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## njl (Apr 24, 2010)

Hi Arnold,

Yep the build is moving along nicely. I made the valve block yesterday. I'll post up some pictures later. I was hunting about in the shop for some more 3mm bolts. I know they are here somewhere but couldn't lay me hands on them last night. Found loads of BA, 4mm and small self tappers. I wish I was a tidy and well organised chap but I'm not and after 51 years of trying to be it's not a lot better now than the day I started!

I've also done a bit more investigation on the saw and I now know what is happening but I don't know why. One of the contactors has a sort of current limit box fitted to it with a lever which set the current limit. The maximum setting is 2.5 amps (which it was set to). Anyway If I just run the saw for a while with no load it will trip out after a minute or two. Normally long enough for me to make any cut I'd want to do in a piece of wood. Once it has tripped it won't reset until it has cooled down. I'm not exactly sure what the current trip is protecting, I'm guessing that it might be the contactor winding current it is protecting. So maybe it just needs a new contactor. I went to a local company Tewkesbury Saw who had an open day yesterday and talked to the owner about it and he has offered to give it a once over for me by one of his electricians so I think I'll take him up on the offer. I'm not very conversant with three phase electrics and I don't want to let the smoke out or more to the point smoke me.

I also took the motor cover off the machine and apart from a thick covering of fine sawdust there was nothing I could see wrong in the motor department. Everything was stone bonkering cold too so it is not a motor overheat type issue. It has two motors one to drive the band and a smaller one to drive the compressor that blows the swarf away.

I can post some pictures if anyone is interest?

Nick


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## Swarf Rat (Apr 24, 2010)

Does that motor have a centrifugal switch to disengage the starting coils?


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## njl (Apr 24, 2010)

Thanks for the thoughts Swart Rat, I see where your going and Ill check its not a sticking motor contact but I'm not sure it does. It has an electronic speed controller with variable speed controller and it has a (very) soft start. The variable speed control works fine before the motor stops.

Well here are a few more steps done on the build.

Yesterday I made the valve body, but as it is very similar to the cylinder machining wise I haven't duplicated the process for you.

Today I made the valve rod and finished off the piston.

Here we are with the lathe in auto feed cutting down a bit of brass to make the valve. It was a slowish feed so I had plenty of time to get some shots I was hoping to capture the chips flying but it didn't really do it justice. I was working on light cuts playing about to get the best finish on the stock. Those specs to the left of the stock are not muck on the lens they are chips, honest!






I used the same method to get a good fit as I did for the cylinder. Get close, cut a shamfer just smaller than required size, so the valve body would fit onto it and then sneak down on the fit. I had quite a bit of stock hanging out of the chuck and as the bar was getting smaller the free end was starting to spring. I didn't get any steadies with my lathe and I have them on the to make list. Meanwhile I use this method with a piece of wood and take small cuts (I just hold it against the stock whilst the lathe cuts). It does work surprisingly well. I was concious of the size difference between the chuck end and free end and kept taking cuts at the same depth to relieve the spring to get the free end down to the same size as the chuck end. 






Here I am reducing the stock to make the air clearance.The pointed tool I'm using gives a better finish than the one in the first photo above. I chickened out at 4.5mm diameter as it was getting hard to control the spring and I didn't want to stuff up the part.

For such a small piece I found this part quite demanding to make, it took a long time for me to make it. I needed to use different lather tools to face the LH & RH valve lobes. A good learning exercise and all good fun.

The next step was to machine the face for the connecting rod to attach. I did this step in the mill. I kept the part attached to the stock so I had something to hold and also had a test piece to try. Being very new to this I've only ever milled mild steel before today and I want to test how the brass would cut before it became new part affecting.







I still had this same job to do on the piston and as I now had the end mill cutter depth set it was a simple job to pop the piston in the vblock and cut it down to the same size.

The finally process was to drill and tap the holes for the rods to connect. I'm still finding it hard to get the centers spot on. I think maybe I should used a smaller drill first rather than gone straight in with the tap drill. Close but no cigar.

Anyway here is the final pic for today. The assembled parts on the frame. Yes I found some more 3mm bolts (they are for an aero engine's exhaust mounting so only a temporary loan to this project.) I knew I had some. 






Looking much more like an engine now. I tried a quick test blowing air into the valve block and operating the valve and it works a treat. More round parts to make for the next installment. I'm flying tomorrow so will catch up again next week.


Nick


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## Swarf Rat (Apr 24, 2010)

Nice progress on your build, it's looking good.

Now, I'm starting to wonder if you may have one of the phase drivers dead in your speed controller (either opened or shorted would be likely to make a motor run hotter). I think you may have one phase always energised instead of being cycled at the necessary frequency.


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## njl (Apr 25, 2010)

Hi Swarf Rat,

Not sure if I gave you a red herring when I said it has a very soft start, I didn't mean to imply that was a symptom of the problem rather it is a feature of how the saw always starts. IE. it doesn't rapidly build up to speed like my lathe does. You could well be right about the problem being controller related. 

Anyway thought I'd show you a couple of pics of the panel and point out the thing that trips out.






And here is an enlargement of the thing that trips.






Looking at the little white lever it has a rather chewed up end so maybe it has been fiddled about with before. To reset things I have to press the red button but it wont reset immediately I have to wait a while (for it to cool I guess) before it will latch again.

Nick


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## Swarf Rat (Apr 25, 2010)

It sounds to me like the circuit breaker is doing its job of protecting the system, something is causing the breaker to trip. Your technician should be able to sort it out quickly with a volt meter. I hope the repair turns out to be quick and easy.


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## njl (Apr 26, 2010)

My saw is going again now, I found a bad connection on one of the phases so sometimes it was only running on two phase. So well done Swarf Rat you were spot on with you diagnoses.

Well my build has progresses a bit further making all the round parts.

I made the bush a press fit into the frame.

In model flying we have a term hanger rash, which is damage done to an airframe when a model it is not being flown. Is there an equivalent for parts getting scratched or marked after they are finished? If there is then this little brass bush suffered twice! First off when I pushed it into the hole a small piece of swarf scratched as it emerged through the frame. Then later on in the build when I decided to place it to one side rather than mount it centrally in the frame to give more room for the grub screw in the crank wheel, I managed to push it into a square 3/8 socket drive hole, when I needed a shroud around the part so I could press it back through the frame with the vice. 

Here we are pre square 3/8 broach marks. (So later on when you see the assembled engine they are not 4 jaw marks.) The axle is still to be cut to final length






The axle is made from silver steel. It's stock form it was 6.33mm. I currently only have metric drills in 0.1 mm steps up to 6mm. Then I have 0.5mm steps. Well a quick test of 6.33mm axle in a 6.5mm hole gave too much slop so I decided to cut the axle down 5.8 mm so I had some leaway to make free and interference fits of the crank wheel and the flywheel.

I found that it's tough stuff to machine. Being thin I had similar spring issue to making the valve part.

Axel done. Next step was to tackle the fly wheel. I had a suitable piece of ali stock for the part. I put it in the chuck and faced the end, drilled the center hole and clean up the circumference, added the bevels. Everything was going well until I started to part it off. Even though I had the chuck done up tight and plenty of ali to grip, the parting tool cutting caused the part to shift in the chuck so it went out of true. I re-trued by refacing it but then the hole on the center was now not exactly in the center. So once I had finished it I mounted to on the axle as an arbor and trued it up again taking very light cuts. I think I got away with it, next time I will drill the hole last.

With hindsight I think maybe I should of cleaned up the end of the stock and then put that end in the chuck so it could get a better grip? The stock did look nice and round but I guess it wasn't perfect.

Anyway here we are about to clean up the parted face. I'm using a lemonade can kindly donated by one of our hoilday cottage guest's in their recycling bin to stop the chuck marking the part, one of my glass beer bottles wouldn't do the trick! I used the dial gauge on the shamfered rim to make sure the part was running true. As there was not much part to grip I took very light cuts using the cross slide self feed. It gave a nice finish (see below).






Here is the crank side of the engine. The crank wheel is also silver steel. I found it too hard for my parting tool to cut so parted it with the band saw and then put it back in the lathe to clean it up. It fits to the shaft with a 3mm grub screw. Why silver steel, well it was the only 1 inch round stock I had.






The finished axle assembly. Piston and valve in their correct position for a change.






And finally a view of the Flywheel and the rhs of the engine.






So just the crank and valve rods and their spacers to make and we are ready for a test run. I might build a set in steel first to protype the engine and prove the valve timing and then re make them in brass to give better aesthetics.

The end is in sight. Hope she runs.

Nick


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## black85vette (Apr 26, 2010)

Looking good. Everything looks like it is lining up well. 

On the flywheel; I have made a mount for a vise to place it vertically on my band saw so I can cut off thin slices for flywheels from round stock.  I have also made flywheels out of flat stock, cut the corners and then put it in the lathe to make it round. Just a preference, but I don't care for parting off large diameters.

Should not be long now!  Thm:


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## njl (Apr 28, 2010)

Thanks for the flywheel tips Black85vette and thanks again to you and the team for designing this training model, I've learnt a heck of a lot from building this engine. I've really enjoyed the process and I have now built my first running engine! Thm:

Well last night I thought I would finish off the last few engine parts but once I'd rough cut two strips of brass from some angle stock I had kicking about and drilled holes in them, I just had to use them in their unfinished state to have a quick play to see if the engine worked. Well I fired up my compressor, set the pressure at 10Lbs, put the air duster attachment on the hose and pressed it over the inlet hole squeezed the trigger and she instantly ran. She was on the induction stroke and just self started and away she went. I then spent the rest of the session just playing about with her. I found that the screws I had cut down and used to hold the crank rod to the crank wheel would gradually self tighten whilst the flywheel screw would gradually loosen, so to continue playing I switched them for their cut off ends. 

At the moment I'm just using some 3mm washers for spacers, so one solution might be to make my spacers threaded and use them as lock nuts or maybe I'll just use a bit of thread locker.

I found that I could even get her to run with just a trickle of air. I had a play about with valve timing too.

Anyway here are some pics for you of the engine with rough sawn cranks fitted. 
















Once I finish up the parts I'll post up a video (that will be a first for me too) and let you see her running. Still to do, I need to make some filling buttons and round the ends of the rods and clean up their rough edges, make the spacers and an air input connection. 

Meanwhile a big thanks to all those of you who have have answer my questions and chipped in with advice. For those of you about to take your first steps I hope my build thread has been of some help to get you started.

Nick


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## black85vette (Apr 28, 2010)

njl  said:
			
		

> I found that the screws I had cut down and used to hold the crank rod to the crank wheel would gradually self tighten whilst the flywheel screw would gradually loosen, so to continue playing I switched them for their cut off ends.
> 
> At the moment I'm just using some 3mm washers for spacers, so one solution might be to make my spacers threaded and use them as lock nuts or maybe I'll just use a bit of thread locker.
> Nick


 woohoo1

Fine job Nick!  Always exciting to get an engine running. Even more so when it is your first.

Great idea about using threading spacers as a lock nut. May have to steal borrow that idea.  I may incorporate that into any future designs.  Most of the time I use epoxy sparingly on the threads at the final assembly because it sets up so quick.

Looking forward to the video.


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## bearcar1 (Apr 28, 2010)

You know, I really do enjoy seeing these first engines being produced by ,'newbies', for a lack of a better word and not meant as demeaning in any way. It is so refreshing to see and hear of all of the trials and errors that were encountered in their construction and how problems were worked around. I especially enjoy seeing "non-complex" set ups being utilized to good results. Well done, Nick, a fine looking engine. You should be proud of your accomplishments. BRAVO!  Do you have plans for a second engine? Or another E-Z modified to suit your own artistic style? We are all awaiting your video, oh yeah, don't forget the "happy dance". We are all such suckers for cheap entertainment :big:


BC1
Jim


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## Swarf Rat (Apr 28, 2010)

Congratulations Nick!!! Nicely done and a bandsaw repair to boot


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## Deanofid (Apr 28, 2010)

Sounds like it's going great, Nick. We're all excited to see it chugging along!


Dean


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## arnoldb (Apr 29, 2010)

Well done Nick Thm:, and thank you for showing your build!

Its a great feeling seeing the first engine run, isn't it ? ;D

Kind regards, Arnold


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## njl (Apr 30, 2010)

Thanks for the complements chaps, it's been great having you along for the build.

Here is quick video clip for you of the engine doing a test run with the threaded spacers fitted to the crank pins. The idea works fine, but they are a little fiddly to tighten up. Long nosed pliers did the trick. The engine is running on 5lbs in this video. The air supply is connected via a small piece of ali tube just resting loosely in the hole with a ring of silicon fuel tube to stop it falling in and fouling the valve. I have the camera in one hand and the air duster in the other so couldn't star in the film too, we'll have to save that for another day when I can set things a little better.


[youtube=425,350]<object width="425" height="344"><param name="movie" value="http://www.youtube.com/v/IB5IE9Wc380&hl=en&fs=1"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="http://www.youtube.com/v/IB5IE9Wc380&hl=en&fs=1" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="425" height="344"></embed></object>[/youtube]

This is my first video on the web hope you enjoyed it. Just got to file the rods and she is done from a metal cutting perspective. Metal finishing is a whole new world to me I know absolutely nothing about it. 

Bearcar1; My next engine will be the ez2. I've already ordered the metal. Glad you enjoyed seeing how I set things up and how I tackled things. I wasn't sure how many photos folks would want or how much detail on how I did it rather than seeing the finished parts, so good to hear you enjoyed what it did, I didn't want folks thinking I'm teaching them to suck eggs.

Arnold; Yep it was great seeing it run for the first time. I was amazed it just ran straight off with no tweeking. It reminds me of when I was a kid (many years ago) playing with my Mamod steam engine.

Anyway I must away, I've now got plenty of swarf to clean up and a workshop to tidy before I can start the next one.

Nick


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## Deanofid (Apr 30, 2010)

Ah, that's just capital, Nick! Runs mighty fine.
You picked a good one to start with and did things up well.
Great to see it on the go. Very good!

Dean


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## SBWHART (Apr 30, 2010)

Very Nice build and cracking runner Nick 

:bow: :bow: :bow: :bow: :bow:

Cheers

Stew


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## black85vette (Apr 30, 2010)

Good job with the video. Looks like it runs really smooth at low pressure. Kind of strange how satisfying it is to watch a little engine run, isn't it?


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## Maryak (Apr 30, 2010)

Nick,

Congratulations. :bow:

Best Regards
Bob


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