My Rube Goldberg

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Philjoe5

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I have a few stationary engines I fool around with. I like to connect them up to a generator via belt drive and see what kind of power I can get out of them. Whenever my neighbors son, age 5, Mr. Will, sees them he comes over to watch them. At times I’ve taken him through the workshop and, of course, many times I’ve run my model engines for him and his mom. Last week Mr. Will asked me if I would run an engine for him. I said, “Sure, which one”? He said, “I can’t decide”. So I said, “How about if I run all of them? Other friends and neighbors stopped by to see this mini show also. So I made a video for you guys. Caution: it’s noisy

[ame]http://www.youtube.com/watch?v=bRI-NhgEeAY[/ame]

Here’s what you’re seeing. I had two model engines running on compressed air, coming from a manifold/filter unit, supplied by a Craftsman compressor that was plugged into an outlet on a generator that is belt driven by a 7 hp diesel engine…A Rube Goldberg if I ever saw one. Enjoy it.

Note to Bob, builder of a diesel ICE. This is my lame attempt at running a model engine on diesel fuel! :big:

Cheers,
Phil
 
Well, you were off of the power grid! It looks like these air engines do run pretty well off of diesel. ;)
 
Phil,

Thats not LAME,

A pretty neat way of operating a multiple demonstration. :bow: :bow:

Best Regards
Bob
 
Phil,

its great you got enough engines its a hassle to run em all at once

mine so far i'd need three cups of coffee ( and one of them will still need coaxing) to run them

only stirling kits so far but i'll finish the woodwork ( hey i gotta make some $$) this week and my toys from Mr Winter have arrived so i'll see where ( and when ) i can get a start on a real engine

good onya Phil keep up the good work

jack
 
jack404 said:
only stirling kits so far but i'll finish the woodwork ( hey i gotta make some $$) this week and my toys from Mr Winter have arrived so i'll see where ( and when ) i can get a start on a real engine

Jack, a stirling is a real engine! It may not be internal combustion or steam, but it is still an engine!! 8)

I am speaking from non-experience here, but I see a Sterling or a flame licker as very challenging project to undertake. An IC or steam engine I think has a little more room for error and still run. Just my $.02!
 
WE, Jack,
I second WE's comments! The first engine I tried building was Rudy Kouhoupt's Stirling. I tried twice, neither one was close BUT I did learn a lot. Then I tried a larger one, same results, except I got closer to having a runner. Next I tried a steam engine - first one ran immediately on assembly. I've built 5 since. They're all runners. Now, I suspect if I went back and started a Stirling I'd have a better chance at making a runner...but man they require great skill in my opinion. If you've made one that runs you've built a great engine :bow: :bow: :bow:

Cheers,
Phil
 
Just as with steam engines, for the beginning hobbyist there's a recommended progression of difficulty with Stirlings.

Whatever you do, don't start your Stirling odyssey with an LTD (Low Temperature Differential) design. These are just too demanding as a first engine. Start with an externally fired convential gamma Stirling. Work from a proven design - you can free wheel when you've got some experience - and adhere to the material and clearance choices in that design.

Start with a design where the displacer and power cylinder are perpendicular, e.g.

stir1.jpg


This will automatically give you the required 90 deg phasing between displacer and power piston without a lot of complex mechanical details.

After that, graduate to a design where the two cylinders are aligned

STIRLING.jpg


There's nothing magic about Stirlings like these. Yes, you need a well-fitted power piston and cylinder but that's true of a steam engine. The displacer is (purposely) a loose fit in its cylinder so it's very forgiving in fabrication. Unlike steam engines, Stirlings like these have no valves so you're spared the effort of making and fitting fincicky bits for same. Building a Stirling from a proven design is more an exercise in sealing and minimizing friction. They're usually very low pressure engines so one needs to ensure that the pressure changes are contained so that every bit of them can be put to work providing power. Operating at low pressure means these engines have very low specific power so friction is more of an issue than it would be in a steam or air engine.

Give it a try. There's something really fascinating about watching something you built convert raw heat from a flame directly into mechanical motion.
 

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