Design and build side-shaft hit and miss engine from bar stock

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G'day Brian.
I never really understood how this type hit n miss mechanism worked until this close up post.
Thank you.
Cheers
John
 
I haven't given up nor ran away. There is an amazing amount of farting around, making small bits, and fitting to this governor. I only have a couple of small spacers yet to make, and the "bump" which gets silver soldered to the brass part in the foreground, for the governor to push on when engaged. Everything else on the entire engine is just repeats of work I have done before, but I want to assemble and test run the governor first.
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Here's a new wrinkle on this type of governor. Obviously you need a spring like the yellow one to move the governor weights and associated bits back into the "not engaged" position when the engine slows down and the governor weights are no longer swung out away from the stempost by centrifugal force. However, I've had to add an extra threaded post and a couple of nuts to prevent the governor from moving too far into the engaged position. If the governor weights fly out at any more than a 40 degree angle, they get jammed there and won't come back into the correct position.
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If you remember, when I was first looking at this project I purchased a set of 2:1 ratio helical gears off Ebay. The cost was under $12 US funds, so I ordered them, figuring "What do I have to lose?". I went ahead and bought a different set of helical gears from DeBolt for $75 US and they arrived promptly and they were fine. I've been deluged by a spate of "real work" to the point where I haven't been able to do any work on this new engine recently. Today my Ebay gears came in the mail, and I'm quite impressed. The Ebay gears are in the foreground, with the gears from DeBolt setting closer to the partly finished governor.
http://rover.ebay.com/rover/1/711-5...0001&campid=5338413729&icep_item=262691511022
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Yesterday afternoon and this morning, I've finally found enough time to finish this governor. I must admit, I had serious doubts about this one working. However, Craig DeShong just completed a hit and miss engine that was bought as a casting kit, using the same design (I copied his) and he got stellar results. His engine runs beautifully. I haven't done anything yet on the actual engine, because I've built as number of previous internal combustion engines, and there will be nothing really "new" about this one----Except the governor.

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This is one of my least favorite jobs when building an engine. I have yet to find a "good" way to trepan the side of a flywheel. It isn't too horrible when using an aluminum center with a steel outer rim, but when you make the entire one piece flywheel from a single piece of steel, this job makes me crazy. There is simply no good way to go about it. I have one side of this flywheel done, except for a clean up cut. The carbide tools cut really well, but leave a rather ugly finish. the HSS tools leave a lovely finish but dull very quickly. When I do the far side of this flywheel, I will make a series of plunge cuts near the center hub (a total of 3/8" deep) and try using a brazed carbide turning tool to make successive cuts from the center out towards the rim.
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So there we are!! One done and one to go. When I machined the second side, I found it to be easier if I took about 6 plunge cuts to full depth (3/8") nearest to the hub with a .093" wide parting blade HSS with the heel relieved quite a lot so it wouldn't rub. At that point I had a wide enough slot to get the end of a brazed carbide boring bar in there, and make repeated passes 0.010" depth of cut from the slot out towards the rim. This took a heck of a lot of cuts, but was easier to control. I will use that same method when I do the second flywheel.
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Following along Brian. I would like to do a side shaft engine some day but with a different style governor. That one looks too fiddley! I learn a lot from you and I thank you.

Jim in Pa
 
And now I have two of them!! My poor little shop looks like swarf mountain, but I'm pleased with the way these turned out. I still need to broach keyways, add set screws, and put in the 1 1/4" holes in the webs, but the lathe work is done. I'm going to completely finish these guys before I start on any of the other parts, but it's all progress.---Brian
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Jim--All governors have fiddly bits. I have built flyball governors, hit and miss flywheel mounted governors, and this type of governor, and trust me, they all have fiddly bits.
 
Who can tell me how to edit my profile? I can't find where to do that now that the forum software has been updated.---Brian
 
Brian, I think that if you click on the little man icon, -actually looks like a chess pawn, at the top right of the page (On my PC anyway) you will go to your profile page.
See how you go.
John B
 
Who can tell me how to edit my profile? I can't find where to do that now that the forum software has been updated.---Brian
You can change almost everything about your profile from the little man icon in the top right of each page. If there's something you can't find give me a yell and I can help you out.
 
Even with having to use the boring head to end up with 1 1/4" holes in the flywheel web, it wasn't that bad. The web is 1/4" thick, so I went around once using the DRO and a 3/8" dia. countersink. Then stepped right up to a full 1" drill, the biggest I have, and went around once with that. Then I put in the boring head and set it to bore a 1.150" dia. hole and went around once, then opened it out to bore a full 1 1/4" hole and went around one more time. It didn't take nearly as long as I thought it would. The keyways are broached in each flywheel and the set screw holes are tapped.
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Jim--All governors have fiddly bits. I have built flyball governors, hit and miss flywheel mounted governors, and this type of governor, and trust me, they all have fiddly bits.

Yes Brian, I remember those fiddly parts on the Kerzel governor that I built. But I got it right the first time!
 
Today I finished up both flywheels. These larger, heavier flywheels are going to demand something heartier than a 3/8" crankshaft. While rummaging through one of my boxes of "things" I found a pair of lovely 1/2" inside diameter ball bearings, so that is what I will use, and make the crankshaft 1/2" diameter. I was lucky enough to find that a piece of 1.5" diameter stock is large enough to turn the crankshaft from solid, so I went to my favourite metal supplier today and picked up a piece of 1144 stressproof steel. Turning crankshafts from solid is not my favourite thing to do, but I have done it before successfully, so hopefully this will go well.---Brian
 

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