Author Topic: Fabricating a Flywheel  (Read 9069 times)

Offline tinglett

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Re: Fabricating a Flywheel
« Reply #30 on: December 21, 2016, 04:27:24 PM »
Thanks all for the advice (and encouragement!).

It's better now, but not perfect.  Still, it's plenty close for me to simply true it all up.  I hope to finish it today and will post photos of this last bit.  Then, I'd better think about starting an engine to put it on, don't you think?  ;D

Todd

Offline tinglett

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Re: Fabricating a Flywheel
« Reply #31 on: December 21, 2016, 09:14:46 PM »
Hmm...as I started to true it up, I noticed the web is no longer perfectly square with the shaft.  At first I thought it was an illusion until I got out a dial indicator.  It's about 40 thousands out of square.  I suppose that could have come from the tapping, but that wasn't vigorous by any stretch of the imagination.  So maybe it just warped a bit from the heat.

Everything else checks out ok.  I think I'll true up everything else and then see how bad it really is.  The only problem is that I can see the little internal wobble it makes, and I know I'll see that when it spins in an engine.  Maybe I'll do a light skim over the spokes to straighten it all up...but I guess that'll depend on how much I need to take off.  In theory that's about 80 thousandths, and that's a big fraction of the 250 I have for the spoke thickness.

Todd

Offline tinglett

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Re: Fabricating a Flywheel
« Reply #32 on: December 22, 2016, 12:43:05 AM »
Finishing the Flywheel

The flywheel was a bit tipsy, but I straightened it some, and then trued it up on the mandrel which is still in the lathe.  Here I faced the side.



Here I'm straightening up inside the rim.  At this point I noticed that the spokes are just a little wobbly.  Somehow they got a bit out of square with the hub.  For now I left that problem as-is.



Here I'm turning the outside of the rim.  I decided to try my boring bar.  This worked well, although I didn't have one for the right direction so I spun the lathe backwards and ran the bar upside down.  It didn't seem to care about gravity  :D.  You can see I'm taking a bit of wobble out of the surface.  Almost done.



A little touch-up on the hub since everything is concentric now.  May as well get all the bits aligned.  I had to take off about 10 thousandths, and I remembered to remove the setscrew!  Note that the rim got quite a bit thinner...but I like the look.



And there it is....



I decided to leave the wobble in the spokes for now.  I can still skim them, but I'm thinking it's not worth it.  They wobble a little, but the hub and flywheel seem quite concentric with each other so the wheel itself isn't wobbling at all.

I'm still mulling over what I'd do different.  Maybe if I cut the spokes after fitting to the rim things might not warp so much.  But it was very convenient to do that tricky work when it was nice and flat.  So at the moment, I think I'd try the same order.  Maybe I'd heat it just a bit more -- getting the whole rim to start turning blue.

In the grand scheme of things I like how it turned out.   Hopefully this log will be useful to someone.  Now this flywheel needs an engine!

Todd

Offline crueby

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Re: Fabricating a Flywheel
« Reply #33 on: December 21, 2016, 11:25:39 PM »
Thats a great looking wheel! Have you decided what engine to spin it?

Offline tinglett

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Re: Fabricating a Flywheel
« Reply #34 on: December 22, 2016, 11:42:58 PM »
I was thinking of building this little gem.  It's the Rocking Valve engine from the Shop Wisdom of Jesse Livingston.  The photo is snipped from that book.



I can't say I've seen a build of this one, though I haven't looked much yet.  I hope there aren't too many pitfalls.  There's a 1/8" thick brass fairing that needs to be annealed and formed.  I've never done that before.  But it's good to learn something new with each build, right? :)

Todd

Offline crueby

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Re: Fabricating a Flywheel
« Reply #35 on: December 23, 2016, 12:01:56 AM »
Thats a nice looking engine. Don't think I have seen that one before. With what you have done, annealing and forming brass will be no problem.

Offline Dave Otto

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Re: Fabricating a Flywheel
« Reply #36 on: December 23, 2016, 12:41:38 AM »
That is a nice looking little engine; if it is the correct size your curved flywheel would look very nice on it.

Dave

Offline Roger B

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Re: Fabricating a Flywheel
« Reply #37 on: December 23, 2016, 11:10:39 AM »
Very nice flywheel build and some useful lessons for the rest of us  :ThumbsUp:  :ThumbsUp: I'm looking forward to the engine to go with it  :wine1:
Best regards

Roger