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I've been working on rebuilding 60's Powermatic model 30 that I pickup
up a few weeks ago. So far I've resurfaced the platen, made a new
sheave/arbor for the disc with I have yet to turn, but now I'm working on
the tracking. The previous owner had turned the drums, and it seems like
they put almost no crown at all in them. Of course with flat drums the
tracking is hopeless, and although I can get it almost stable with some
very fine adjustments, it will always have at least a slow creep one way or
the other.

So my question is, does anyone have opinions on the best shape or size
of the crown? Should it be an even curve or a peak? Slight plateau
perhaps? And how much higher should the center generally be? Belt life
is probably not much of an issue because I abuse and go through them
quite quickly anyway, so if the range is .005" to .015" I may like to lean
toward the .015". Should the idle drum have a higher crown than the
drive drum?

If anyone has any experience with this I am very open to suggestions. Or
of you have a 6" belt sander that tracks like a dream and feel like
measuring out the drums that would be very much appreciated.

David Collins39004.5002199074

_________________
Eschew obfuscation, espouse elucidation.

Dave,

Post this to the NEL Yahoo Group also. I believe there's a couple guys there who may have useful information.

Don

_________________
"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

Thanks Don,

There seem to be so many woodworking and tool groups that I really had no
idea which may be worth posting on. I'll try there.


   Edit: What does NEL stand for? - the closest things I could find on the web
were Network Engineering Limited and Non-European Languages groups. Is
it a woodworking or tool group?David Collins39004.6101273148

_________________
Eschew obfuscation, espouse elucidation.

David, I think NEL=New England Luthiers.

_________________
Dave Rector
Rector Guitars

Well, nevermind. I pulled the drums and turned them last night enough to
at least make it usable. I roughly copied the drums on my Jet 6DC,
although I didn't want to use that as a model because it's not the greatest
tracking either (although I think that's more due to the completely idiotic
arrangment of the tracking adjustments ).

Anyway, I couldn't fully crown them anyhow because I thought too much
material was already removed. I'll have to keep my eye out for
replacement rollers, so if anyone here has any Powermatic drums laying
around let me know. I'm sure I can order them from the local tool store,
but they would probably cost at leat twice what I paid for the sander.

BTW Hesh,
In case you haven't been down State street lately, our local Electric Tool &
Equipment has moved over off Airport Blvd. At least they were in the
process of doing so when I was there a few weeks ago.

David Collins39005.6168865741

_________________
Eschew obfuscation, espouse elucidation.