Duclos Odds 'N' Ends Engine

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olympic

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I don't post here often because I'm not much of a machinist, but for once I seem to have made some decent progress on something, so I thought that someone might be interested in what I've done.

Here's a Philip Duclos Odds 'n' Ends engine in 1.5 scale that I acquired about two years ago. Flywheel diameter is just shy of 8 in., or 20 cm. if you prefer.

Though almost complete, it still needed a few things.

I made a muffler to my own design 😜.

IMG_20210415_145137_7056.jpg


I tried my hand at making oilers and a grease cup for the crankshaft (the originals were ugly zerk grease fittings). I replaced another zerk fitting with a small hit and miss oiler for the piston.

IMG_20210415_145126_1126.jpg


I had to make a return spring mechanism for the exhaust/lockout arm, as it didn't always want to follow the cam.

The timing was off by perhaps one gear tooth, so I adjusted it. I think it's right now. Time will tell, as it were.

The original engine build article suggested making a fuel tank from an empty tuna or salmon can, or something like that. I made one from an empty cat food can, but it was so outstandingly ugly

IMG_20210415_145216_6192.jpg


that I scrapped it and adapted an incomplete hit and miss engine oiler to do the job.

IMG_20210415_145029_1921.jpg


I like the "clear view" look.

Today I tested the electrics using my "universal power box," a buzz coil and battery housed in an old leather dynamite case,

IMG_20210415_150329_4325.jpg


and all looks good.

When the current rainy season ends, I'll take it outdoors and give it a whirl. Eventually, I'll make a small drive pulley for the non-governor end of the crankshaft, and fabricate a proper gib key for it all.
 
I think you discredit yourself.

I like the way your engine looks and I appreciate the personal touches like the muffler and the adaptation of the oiler for a fuel tank.

I will be watching for the video and I am confident that you will have it running.

--ShopShoe
 
The odds and ends engine is next on my list after I finish my Webster. I really like your improvements and especially your fuel tank! Congratulations on finding a great project and I look forward to your video of it running.

John W
 
Well, I took it out today and tried to run it. No joy.

Whereas I saw a healthy spark in the basement, when I got outside I couldn't seem to get any response. I checked all the wiring, and it still looked good. I took my power box and checked its operation on the bench with both the "proper" spark plug for the engine and a totally different one; they both fired great, but when I tried each of them by laying them against the engine block that nice purple spark was absent. I know that the buzz coil is working as it should, as it gave me a couple of 20,000 volt reassurances along the way.

Eventually, though I don't know why, I started getting the odd pop out of it (tried different fuel, too: gasoline instead of the Coleman/WD40 mixture), but still no go.

Finally, I noticed that the crankshaft gear wasn't turning with the crankshaft, and discovered that the original builder had used a set screw to fasten the gear to the shaft, and that it had recently fallen out, so the exhaust valve was never opening. When I took things apart, I found both a keyway and holes in two different places on the crankshaft that testified to attempts to pin the gear in place. There is one hole between two teeth in the gear, threaded 4-40 and which seems to have held the lost set screw, but it doesn't seem to match anything in the crankshaft.

I think that I can take advantage of one of the two transverse holes in the crankshaft, enlarge the 4-40 hole between the gear teeth, and use a 1/8" roll pin to hold the gear in place.

If anyone has any advice for me on this, I'd certainly appreciate it.
 
Hi
I've not reached that stage of the build yet, but the drawing suggests a 1/16" diameter hole is drilled right through the crankshaft gear. The hole being drilled between teeth. A 1/16" x 1/2" dowel pin or roll pin is used to secure to the shaft.
The crankshaft shows a 1/16" dowel pin hole drilled right through the shaft. The exact position being located with the bearing and gear in place.
If I was in your position I would try to drill fresh holes as detailed above.
I can't provide you with a copy of the drawings as these are copyrighted.
If you are in the US you could probably get hold of a secondhand Shop Wisdom book at a decent price. I purchased mine new from Village Press.
I hope that helps.
Cheers
Andrew
 
Well, I took it out today and tried to run it. No joy.

Whereas I saw a healthy spark in the basement, when I got outside I couldn't seem to get any response. I checked all the wiring, and it still looked good. I took my power box and checked its operation on the bench with both the "proper" spark plug for the engine and a totally different one; they both fired great, but when I tried each of them by laying them against the engine block that nice purple spark was absent. I know that the buzz coil is working as it should, as it gave me a couple of 20,000 volt reassurances along the way.

Eventually, though I don't know why, I started getting the odd pop out of it (tried different fuel, too: gasoline instead of the Coleman/WD40 mixture), but still no go.

Finally, I noticed that the crankshaft gear wasn't turning with the crankshaft, and discovered that the original builder had used a set screw to fasten the gear to the shaft, and that it had recently fallen out, so the exhaust valve was never opening. When I took things apart, I found both a keyway and holes in two different places on the crankshaft that testified to attempts to pin the gear in place. There is one hole between two teeth in the gear, threaded 4-40 and which seems to have held the lost set screw, but it doesn't seem to match anything in the crankshaft.

I think that I can take advantage of one of the two transverse holes in the crankshaft, enlarge the 4-40 hole between the gear teeth, and use a 1/8" roll pin to hold the gear in place.

If anyone has any advice for me on this, I'd certainly appreciate it.
Hello
Regarding the lost gear set screw. An option would be to is to machine a long set screw 4 x 40 with just enough of the threads to hold in the rest of the threads machined off to a diameter to say a reamed hole this would effect be a pin to hold an much easer to put in an if you have to removed no pounded round with these small parts.
Harvey
 
Thank you, everyone, especially Harglo, AndrewW, and a41capt, for your help and support on this. I intend to persevere until this engine works.

I think I'd like to follow AndrewW's suggestion and re-drill the crankshaft and gear for a roll pin. Andrew, I do have the 1986/87 "Home Shop Machinist" articles for this, and a41capt has given me some advice on timing, so I think I can do this.

I've decided to fill the existing drilled holes in the crankshaft with JB Weld, as they are too big and sloppy, and even the one tapped 4-40 is stripped. This should restore a bit of strength to the crankshaft.

Andrew, I can drill for a 1/8" roll pin, as the existing 4-40 hole in the gear is just smaller than 1/8" and my crankshaft is .625" in diameter rather than the .375" called for by Duclos, because my engine has been built to 1.5 scale (besides, I happen to have some 1/8" roll pins). As for the gear, it has an even number of teeth, so when I drill between gear teeth the hole on the other side will appear between teeth, too. It is my intention to drill the gear and shaft in situ, in hopes that this will prove to be the most accurate method.

I'm going to practise installing roll pins on a bit of scrap before I move to the engine.

Aside from that, the engine is becoming more interesting as I proceed. After I shut off the fuel flow I found fuel dripping from the lowest point of the fuel line and at first wondered whether my snazzy fuel tank was leaking, but it turns out that the taper in the carburetor needle valve was pretty rough and would not shut off the fuel flow completely, so I sat down with the needle and a small diamond file; now I can turn the crank to work on things without drawing a slug of fuel and flooding the engine. I'm sure I'll find more surprises along the way.

Comments and suggestions from all are welcome; I don't pretend to know just what I'm doing.
 
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Make sure you have the valve timing set properly, before you try to make anything perminate.
Rotate the flywheels through and compare the valve timing and the ignition timing.
If you decide to pin, use a pin made from aluminum or brass welding rod.
I usually us a set screw for set-up, before final pining or keying in place.

These engines from my experience, ran wet, meaning the exhaust was not dry. Your muffler is very ristrictive, you may want to put some small washers betwen the muffler halfs. This will let the slober drain out of the muffler.

Last question, are you rotating the flywheels clockwise with the carb. to the left hand side of you?
 
Thank you, Chiptosser.

I'll be very careful to get gears, crank, etc. in the proper relative positions before I make things irreversible.

I already found out what you mean about the engine's running "wet" so I will certainly place some washers between the muffler halves.

As for flywheel rotation, I have a few full-size engines, so I am all right with that.

Your suggestions are very welcome.
 
Just a little update.

Though I can't take this outside till all the snow is gone (April really is the cruelest month), I am almost ready to.

I managed to drill the crank gear on the shaft and fix it with a roll pin. Despite all my careful measuring and positioning, it came out just a tad off, but not enough to worry about.

Then when I put the cam gear and flywheel back on, I noticed that the camshaft was lacking the shoulder on the outer end that should keep the cam gear from wandering out toward the flywheel and hitting the governor lockout arm. I checked the drawings, and they did indeed show the camshaft with a shoulder, but the builder hadn't made his that way.

As I saw it, I had a choice: make another camshaft, or install a circlip/snap ring just outboard of the cam gear. The circlip won, and I did it right!

Now I'm waiting for the weather to accommodate me.
 
Still working at this.

I thought I was pretty well ready to go, then noticed that the flywheels were a really sloppy fit. Turns out that the crankshaft and flywheel keyways were not exactly accurate, and it took forever to find the combination of shims that would make the flywheels fit tight.

Then I discovered that the governor lockout arm was a) too short to engage properly and b) shaped such that if it ever did engage it would interfere with the arms of the centrifugal governor mechanism.

It's taken me forever to overcome these difficulties (I made three different lockout arms and did a lot of careful filing), but I think I have done it. I'm now worried that the governor springs are too stiff, but only a trial will tell me about that.

Going to try it soon....
 
Shims will work out! Make a tapered key.

Thank you. If you look earlier in this thread, you'll see that that is what I intend to do eventually.

For the moment, though, I can rest easy, as the ends of crankshaft are drilled and tapped, and the flywheels are bolted on. Ugly, but effective.
 
Hi. Just an update. I made my gears a few days ago. I converted to mod 0.5 which results in finer teeth - I don't have any 32DP cutters. This will enable more accurate timing but drilling a 1/16" hole for the dowel pin will be difficult. I've decided to make another crank gear with a 1/8" boss on the side to take a couple of grub screws. This will mean I will have to take 1/8" off the side if the main bearing. I explain this in my #MT41 Part 6 Conrod YouTube video which is due out soon.
All the best.
Andrew
 
That's a good idea, Andrew. I guess I could have done that with mine, but I didn't think of it. Besides, I had the room between teeth for a 1/8" hole.
 
Yeah - if you have the room between teeth it's definitely the easiest option. I hope you get it up and running soon.
Good luck and all the best.
Andrew
 
Working on it, Andrew.

Right now (and for the next few days) it's just above freezing and raining outside, and I don't want to try it indoors.
 

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