Acme screws and pre-load nuts was:Re:Re:greetings

--- In CAD_CAM_EDM_DRO@egroups.com, Jon Elson <jmelson@a...> wrote:

>

The spring method works

> fine with
> ball screws, but will cause VERY accelerated wear of not only the

nuts,

> but the
> SCREW too!
>
> Jon

Yep! becouse the of the lead accuracy of +-.003 per foot the nut
would be tight at one end of the screw and losse at the other end
causing it to wear out fast.the preload nuts made by BSA does't wear
very fast becouse it's made of delrin(acetal) and it conforms to the
lead error,The only one that could fit the grizzly would be the 3/8"
with a maximum load of 25lbs for backlash free.As you increase the
load the nut backdrives and backlash is there.
it would be very easy to excede the 25lbs load on the grizzly
becouse of friction.I should work ok on ballbearing ways(very litle
friction)