You know your ballscrews are aligned when...

I'd just like to pass along a little tip:

You know your axis and your ballscrew and your preload are all in sync
when there is no play/backlash anywhere and when you can spin the
ballscrew very fast by pushing on the slide with a force of about 40
pounds. This is before the servo motor is connected to the ballscrew.

That is our standard of alignment/setup. The slide needs to be able to
spin the ballscrew. This morning we had one that wouldn't and traced it
to an alignment problem. Don't assume your castings are square.
Measure from a machined surface.
--
Kim Lux <lux@...>