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miker
07-24-2006, 02:40 AM
That post turned into a "classic keeper". I just wanted to add something to gundog's begining post. In Harold Hall's "Lathework a Complete Course" he doesn't use a mallet but suggests the following. "Advancing the cross slide slowly, and with a small piece of wood in the toolholder, eases the workpiece to run true as the lathe is TURNED BY HAND. The chuck is initially only lightly tightened.". I guess the blunt piece of wood pushes the work true and then you swing off the chuck key.
Thanks for starting that great thread gundog. :)

Rgds

stuntrunt
07-24-2006, 11:10 AM
Thats how you center the metal disks whenmetalspinning:
If you need a shape without a hole in the bottom, you tighten the disc between the mould an a pad thats on the tailstock center. You then turn on the lathe and while (carefully!!!) loosening the tailstock you use a long piece of hardwood to force the disc to the center...
Even a few years of experience don't make this less frightening...

miker
07-24-2006, 06:42 PM
My lathe only goes to 1500 RPM. Would that be fast enough while you are loosening the Tailstock?? :)

stuntrunt
07-25-2006, 09:59 AM
For a 5 inch disc, ... yes. It needs enough speed. Too slow and you're just pushing the disc about. I do discs up to 70cm across... they're really scary ;)

gundog
07-25-2006, 06:10 PM
Thanks Miker,
I am not sure my info was worthy of saving for the future it seems some just think you need to use the 4 jaw but for me I can resonably set up in less than a minute to within .001" which is more than good for most of what I do. I am no machinist and it takes me about 20 minutes to dial in my 4 jaw and many times I get no better results.
GD