Re: [CAD_CAM_EDM_DRO] Drill-Mill CNC conversion design.

Hey CADMAN, nice drawings!
The only thing I could suggest is to make the X nut holder wide enough to
screw in a ballnut on each side so you could adjust the backlash. You would
need a way to clamp down on the threads to keep them in place after
adjustment.
I bought some 3/4" screw and three nuts from McMaster and I was lucky that
one of the nuts only had .0025 backlash - I put it on the Y axis. The other
two have .007 - .010 I'll use them on the X axis. I don't think I'll get to
zero backlash because of the rigid nut mounting - It'll depend on the
accuracy of the screw.
As for the trust bearings, I just used el-cheapo deep groove ball bearings
in stead of angular contact bearings. It takes two and I installed them
just like angular contact bearings. They seem to be just fine. Maybe not
for a production environment but for home hobby use I think they'll last
quite a while - and I can replace them all for less than the cost of ONE
angular contact bearing.

Joel

----- Original Message -----
From: <cadman@...>
> I did not show preloaded ballscrew nuts in the design, I figured I
> could add them if I was not happy with the tolerance that a single
> nut gives. The cost of the preloaded nut scared me away. My use of
> this machine will not be for business of any kind, just making parts
> for my entertainment.
>
> My web site is http://24.12.163.105/cnc/
>
> CADMAN