Re: [CAD_CAM_EDM_DRO] Re: Z axis conversion

Hugh Currin wrote:

>
> I'm thinking about this also. I'll get X & Y going then Z, but I'm
> still thinking ahead.
>
> I don't see how the screw could come loose from the quill? Any scheme
> I think of restricts it from rotating, thus unscrewing.

The problem is the point of attachment to the quill. There is a single 3/8"
(I think) bolt that attaches the link to the quill at the place where the stop ring
was attached. That is a fairly weak connection, and the constant up/down
flexing of the link/bolt/quill junction may round off the end of the link, turning
it into a pivot point, or stretch the bolt. I haven't had the problem of this
coming loose, but it is, I'm sure, the place where my backlash is coming
from.

> I've alternately thought of putting a split collar clamp around the bottom of
> the quill. A ballscrew mechanism can then be attached to this collar/plate.

Any sort of vertical link, if sufficiently stiff, should work. Possibly it would work
better than the horizontal link from ballnut to quill, as it would be less prone
to develop a bending moment. On the other hand, the longer the links
are, the more prone to developing some sort of flex, twist or whatever.
But, a big collar with an 'ear' attached to the quill could be a real pain
as it runs into clamps, workpiece protrusions, etc. Definitely something
to consider carefully before doing it.

Jon