re:Re: leadscrew bearings / machine design(2nd gif dwg)

Jan:

I would like to know more about your ballscrew mounting methode.
Instead of getting very wordy, is it like methode A, B, or, C. In
the drawings stackup2, and 3 gif, but with more distance between the
bearings. Also i am getting confused if a ballscrew is supposed to
be held in compression or in tension.

Wally K.

--- In CAD_CAM_EDM_DRO@egroups.com, JanRwl@A... wrote:
> Sorry to disagree with learned wizards, but, though very, very
stupid and
> very, very, very ugly, I had been there, done that, and the most-
rigid and
> "bestest" way to do the ends of a lead-screw are to have two
SEPARATE
> angular-contact bearings on EACH end (total, four per screw!), each
pair set
> at least twice the screw-major-diameter apart (between them), or,
at least
> twice major screw-dia. plus one bearing-thickness "on-center".
Really! Just
> havin a pair of bearings with "no" space between them (oh, maybe
just a
> spacer between the two inner-races) is no-where NEAR the same as
the
> "spaced-apart" pair! Unless you are talking a total screw-length
no more
> than, say, ten times the major-dia.!