In article , Jack says...

I have some ball screw
slides at work, and when the stepping motor is de-energized,
it takes very, very little force to move the slide and spin
the ballscrew.

On manual small lathes or mills?

In this case they were crossed slides for some motion
control experiments. If the rail was up-ended a bit, the
slide would zip to the end, just from gravity.

The small stepping motors generated so much linear force
that one had to be really, really careful not to get
an appendage caught between the slide and the end stop.

You guys are going to have to be more careful. You may be stifling
genius here. These guys may grow up to be your bosses. :)

Heh. Just 'cause he's the boss, that don't make it right!
Sometimes the hard part of dealing with the boss, is being
tactful when explaining that some part of his plan is
technically wrong. Incorrect. Won't actually work.
Which is actually one reason why I like my present one.
He's right most of the time so I don't have to do that
dance, hardly ever.

Jim

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