Chuck--I'm running it at about 55 PSI in the video.cfellows said:
Another Chuck Fellows engine as built by Brian rupnow
- Thread starter Brian Rupnow
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vlmarshall
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That sounds great! I'd like to hear it with aluminum flywheels... could you run it with only the governor flywheel?
PROBABLY---Vernon said:
hammers-n-nails
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what kind of loading device do you have in mind? i would like to build one also but about the only thing i could think of was to find a small generator or make one from electric motor and light up blubs or something else that could be seen visually. but i can imagine that not working.
hammers-n-nails said:
Very simple--An 8" diameter x 3/8" thick disc with a 3/8" hole in the center, supported on a 3/8" diameter shaft with a groove around the outer diameter of the disc for a 1/8" o-ring drive belt. One half of the disc will be solid, the other side will be all machined out. An o-ring drive belt from the non-governor flywheel will drive the disc. When the solid side of the disc is being "lifted" by rotation, the engine will be under load, so will "fire" on every stroke. As the solid side of the disc rotates "over center", gravity will assist the engine to rotate it, consequently the engine will "race" under no-load condition---the governors will disengage the cam, and the engine will "miss" untill the solid part of the disc starts to "lift" again.
vlmarshall
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Ha, that'll give it a nice "oilfield" sound, for sure.
hammers-n-nails
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a fine idea, the disk will be rotatng very slow i assume what ratio will that make? it wont work for me because my engine doesnt have a governor. i did make a crude dyno one time that i believe is called a prony brake to fit the flywheel. made it out of two pieces of plywood on the band saw, hinged at the back with a screw on the front to adjust the clamping force. it seemed to work fine and did give readings very near what should be expected from calculation, the problem is that it makes alot of heat and can only be used for a few minutes at 100% load.
Some folks have been asking me about the springs that I used in this engine. ---I just measured the spring that operates the 1/4" diameter sliding valve inside the cylinder head.---It is 0.19" o.d. x 0.023" dia. wire x 1.4" free length and the pitch is measured at approx. 0.077" . The spring which keeps the valve in contact with the cam is 0.25" o.d. x 0.023" dia. wire x 1.5" free length and the pitch is approximately 0.1" (Note that in the final build of my engine I departed from the blueprints in that area). The spring in the governor is 0.31" o.d. x 0.020" wire x 3/4" free length x ??? pitch (I've lost that spring--when I disassembled the hit and miss valving to put on a conventional valve system, the spring escaped and was last seen flying under my desk at 300 MPH.)
mklotz
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Thanks for that, Brian.
Also not specified in the prints is the length of the floating piston in the slave valve. By scaling the print I make it out to be about 0.375". Does that sound about right? (I doubt that it's very critical.)
Also not specified in the prints is the length of the floating piston in the slave valve. By scaling the print I make it out to be about 0.375". Does that sound about right? (I doubt that it's very critical.)
Yes, it is 3/8" long.---Brian
One thing I have to make clear---There was nothing scientific about my selections of the springs that I used. We have a local (to Ontario) nut and bolt company that has a selection of springs in a grey metal box. I am sure EVERY fastner company has the same selection of springs, probably in the same grey metal box!!! I just went in and purchased small, light compression springs that were the correct diameter to fit my application and hoped for the best---and they worked.
