Building a twin cylinder inline i.c. engine.

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Today I got up, took one of my super addictive oxy-codone pain pills, and came downstairs to make a bottom for the crankcase. Everything worked out very well, the bolts all fit. Now I'm off to eat some lunch and spend the rest of the day reading.
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Modeling the cylinder heads almost exceeds my Solidworks knowledge. Some of the commands I type in to form the solid model are only used about once every five or ten years. There are about three hundred commands to remember, and when I only use them every five or ten years, I forget them. I do have an excellent book, and if I really get stuck I can look them up.
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Cutting fins on a cylinder head is---labour intensive!!! I'm well pleased with the results, taking full depth (0.300 inches) cuts with an 0.094" circular blade, but there is a lot of crank turning involved. I hope to finish this one off today, do another one tomorrow.
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Cutting fins on a cylinder head is---labour intensive!!! I'm well pleased with the results, taking full depth (0.300 inches) cuts with an 0.094" circular blade, but there is a lot of crank turning involved. I hope to finish this one off today, do another one tomorrow.
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Lovely, those fins really do add to the look of the engine.

If you have to do a lot of parts like this, it might be worth getting multiple saws and ganging them together on your arbor. That's how they did the cooling fins on old radial engines, presumably with some interesting fixtures!
 
Just the almost impossible to machine clearance notches for the rocker supports left to do. ;)
 
Can someone please direct me to a post about using a distributor on a two cylinder engine. I haven't done that myself, and would like to know more about it.----Brian
 
Wowzah!!! Both cylinder heads are finished and installed, and the rocker arm supports as well. Next up will be the rocker arms.
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I can't read the number on Brian's spark plugs, but I did find these readily available on ebay.
They may be a different size than what Brian is using.
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The guy who makes these uses 1/8in. ceramic tube, inserts his own wire centre electrode, and makes a steel body, 1/4" x 40 thread... Uses high temp epoxy to assemble them. Only ever had 1 failure when the ceramic popped-out because the epoxy had cooked. He has changed to a higher temp Loctite product now I understand.
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You can see it on the side of the next engine. (1/2in bore and stroke?)
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He made about 25 parts of everything for the 14 cylinder radial. - including the spark plugs... - because he can.
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I have tried to expand the spark-plug in the tin displayed at the front of the smaller radial...
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And a couple more with spark plugs.
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He Makes steam engines smaller scale, because he can. Drilled over 25 jets and 8 burners before he got one right for that boiler on his smallest engine.
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And in his off-beat moments makes wonky engines... with nothing in line... Steam punk?
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All working...
Puts me to shame.
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1/4"-32 sparkplugs are easy to find. I only found one source of sparkplugs with a 5/15 or M8 threaded nose, and they were in china. I ended up redesigning the cylinder heads to accept the M10 threads found on a commercially available sparkplug.---Brian
 
I would rather fight a tiger in his cage than make these little pieces of jewelry---the rocker arms. They are so small, yet they set right up on top of the engine for God and everybody to see. The only thing left to do now is trim off the overlength axles for the hardened ends and then they can be mounted on the rocker arm support brackets.
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