RE: [CAD_CAM_EDM_DRO] Re: fitting ballscrew ends

Marcus,

I think the cnc hobbyist would be reluctant to pay even $50/end for
end machining of his surplus ballscrews. That's $300 for an xyz
machine.(feel free to correct me on that :) )

So he would want a way to make his own accurate ends on a
HF mini lathe or something.

He could have the enjoyment of turning these end caps
in his own shop.

As far as holding the balls in place...I mentioned a dab
of glue...but a simple loosly fitting split ring with 6 holes
might do as well. Like a ball retainer in a bearing.

I can't see any way around pinning. Set screws perhaps... but
that would be questionable. As long as the case is hand ground
off in a couple areas where the hole is drilled it wouldn't seem
to be hard. Heck...I often drill taper pin holes with a hand drill.
It doesn't have to be centered or anything...just there.

The epoxy is problematic due to shinkage. It must bear shear
and bending loads...the balls are just for alignment.
They would quickly brinnel if they carried a load.

BUT...if the epoxy were slow cured in a cold environment (0-5c)
it would swell back enough (.005 mm or so) on warming to at least
be line to line.

BTW last time in Chicago I saw a big ballscrew grinder in one
of our division's bone yards. 36" segmented wheel. Custom machine.
One of my colleagues designed it. Bet it's scrap iron now!

Les

Leslie M.Watts
L M Watts Furniture
Tiger Georgia
(706) 212-0242

Main page:
http://www.lmwatts.com
Engineering:
http://www.lmwatts.com/shop.html
Cnc surplus for sale:
http://www.lmwatts.com/forsale.html
Carved signs:
http://www.lmwatts.com/signwp.html


-----Original Message-----
From: CAD_CAM_EDM_DRO@yahoogroups.com
[mailto:CAD_CAM_EDM_DRO@yahoogroups.com]On Behalf Of Marcus and Eva
Sent: Saturday, June 11, 2005 1:19 AM
To: CAD_CAM_EDM_DRO@yahoogroups.com
Subject: Re: [CAD_CAM_EDM_DRO] Re: fitting ballscrew ends


Hi Les:
I like this idea much better; it's certainly much easier to do for the
price point you're talking about.
Probably better concentricity too.
The hardest part will be getting the balls to stay where they're supposed to
as you slip the stub shaft over the end of the screw.