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Old 01-03-2012, 10:44 PM   #11
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Default Re: Wobbly engine plan for critique.

Say Mike, now it looks like you are cooking with gas. Do you have dimensions down yet? I ran across a packet brand new miniature ball bearings that I would be ideal for this engine. I'll have to find them again in the tool chest and verify what size they are. Keep up the good work.

Jim B.

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Old 11-16-2016, 02:52 PM   #12
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Originally Posted by Thegsey View Post
As promised, attached are the revised plans. I have tried to take in as much of your ideas as possible. Please let me know what you think.

Thank you very much!

I am rather new to steam engines; but your design looks like something I could accomplish. I have downloaded the revised drawings but see that a number of the compounds lack dimensions. Is there a set of dimensioned drawings?
If so could you email a set to the address below
Bikerbob@magma Dot Ca
Thank you for your attention

Robert Wager

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Old 01-04-2017, 02:12 AM   #13
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We build a similar engine in the Intro to Manufacturing Operations class here at the university that I work at. We have found that hole placement is critical for best performance. As the spacing of the holes gets closer together the hole size has to get smaller but the cylinder has less distance to travel. If the holes are too close the pressure needs to increase (because the holes have gotten smaller) and you need a flywheel with a large moment of inertia (I) to get you over the dead spot at the top and bottom. As to flywheels a larger diameter, thinner one is better than fat small one as there are less issues with overhung support.You can calculate "I" this way:
Mass moment of inertia = (1/2) * m * r^2
m = density * (thickness * Pi * r^2 )
So I = (Pi/2) * density * t * r^4

It is also important tho make sure that you guide the piston all the up and down in the cylinder. If yo let it come too far out of the cylinder it will rock and you will cause excess friction.

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