Re: [CAD_CAM_EDM_DRO] Re: Sherline Z-axis ballscrew feed.

Hi Dan, lists,

(May have started on CCED, but I think other lists might want to pick up
on this thread)

Instead of trying to fit ball screws to the Sherline, I think we ought
to copy the method used on the other axis.

As the star nuts on the X & Y axis have a mating part that can be
clamped (newer mills/lathes), I wonder if we couldn't make a similar
star nut for the bigger Z axis leadscrew, and a mating start nut that
would be secured to the saddle nut with an allen head cap screw. I
don't have the hardware in front of me, but seems like it could be
made.

Anyone remember if the Z axis lead screw is left handed? I don't recall
that it is. If not, then a standard tap (3/8-?) could be used to make a
new nut (or a discarded locking lever could be used).

Then some very simple "teeth" could be cut on it's OD to form a "Z axis
star nut" (I'd make mine thicker, say 1/4").

Next, a similar sized and toothed nut with a smaller clearance hole for
an 8-32 or so thread could be made. Not hard, bronze or brass rod.

The saddle nut would have to be removed and drilled for this 8-32 thread
at an appropriate distance from the center of the leadscrew to allow the
proper mating of the two "gears".

The teeth of our two star gears needn't be perfect, they won't do much
turning!

Perhaps Sherline would even be willing to make this an accessory or
product!

Alan KM6VV
SherlineCNC
(Yeah, a gear-cutting project!)


"Statman Designs, LLC" wrote:

>
> The CNC-Ready versions of all Sherline mills are supplied with a non-locking
> saddle nut. I think I have an extra locking saddle nut or two lying around
> from a manual Z-axis milling column that I haven't used in 3+ years. Maybe
> I will scavenge that.
>
> Thanks,
>
> Dan.