How would you make a one piece model crankshaft

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DIX
Posts: 114
Joined: Sun Jul 27, 2003 11:08 am
Location: Iowa

Re: How would you make a one piece model crankshaft

Post by DIX » Tue Feb 15, 2005 12:38 am

Bob W.

Actually I thought of using a parting tool and I do have a hand crank for the spindle and if it takes a week of cranking I can do that too but what worries me is that parting tool sticking out 1 1/2". It doesn't look very safe. Well I have several so that's not a problem. :-)
What about getting a good finish on the bearing surface this way?

Oh yeah!! The big question is how to machine off the big slug of metal on what would be the backside of the journal. This will be about 2 1/2" in diameter with the con rod journal offset from center by 3/4". It's a lot of metal to gnaw away with a parting tool set up like in your picture.

Dick

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Bob_W
Posts: 108
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Location: Central PA

Re: How would you make a one piece model crankshaft

Post by Bob_W » Tue Feb 15, 2005 7:21 am

Doug:

You should try to rough out the shape as much as possible before beginning the lathe work. The finish I obtained was pretty nice and just needed a little polishing with a Cratex stick. You may obtain different results depending on the material you are using.

While set up to turn the main shafts you can cut the material that is outside the rod journal and get a surface that is then concentric to the rotation of the crank. Light cuts will be required when doing that with the large diameter, interupted cut.

Bob W

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