Hi, all.
Finished building a new bench top router and am having the following problem. When I power down, the Z axis drops until it hits something. The Z has 25mm Hiwin rails and carriages, and weighs about 35 lbs. It is powered by a Clear path nema23 driving a 1605 x 350 rolled thread ball screw, supported at both ends.
What is the best option for stopping this? I hate to add a spring to the side as this would eat up X travel.
If I turn off the motor enable power it drops very slowly, but killing the power to motor allows it to drop fast enough to hurt you if you got in the way. I gotta fix this. Your ideas are welcome.

Ben