Re: please help........

--- In CAD_CAM_EDM_DRO@y..., dazedNconfused <tattoos4unme@y...> wrote:

> by capturing the far end of the screw, i assume you
> mean with a mounted bearing of some sort. as i just
> stated, its not machined an that end.
>

Indeed. The loose end will tend to flail about and vibrate at
different lenghts and rpm's. There are some physics formulas that
describe the oscillation of an object supported at one end. The
frequency of vibration would be a factor of length (the amount
sticking out past the ballscrew) and the energy applied as rotary
movement. Needless to say, heavy undamped vibrations are rough on
the equipment and play heck with accuracy.

If you don't want to deal with machining the ballscrew end then
perhaps you could find a bearing with an ID that matches the major
diameter of the ballscrew and fashion a mount. You could get by
without a keeper nut if you made sure the mount captures the bearing.

I just cut and modified three 7 ft 1" Warner ballscrews I scavaged
off of some equipment. I machined them to match the original ends so
I could use the same bearings, mounts and keeper nuts. Even cut down
they were over 68" so several feet were sticking out of the lathe
headstock. I had to build a support to keep them from whipping
around during machining. Carbide tools, lubrication and slow cutting
are the secret.

On one of them I had to remove the ballnut and of course the hundred
or so tiny ball bearings. Putting that all back together was a
painstaking job.