The lead screw needs to be stabilized axially. The lead screw should turn, but not move any other way. The method to keep the lead screw stable is to use two bearings with ID (inside diameter) that match the diameter of the lead screw. The bearings are positioned before and after a stable structural part. A collar is positioned at one side of the bearing assembly and another collar, or end of a coupling is positioned at the other side of the bearing assembly.
How many times do you need to turn the handle to move the lead screw 1 inch?
For our 5 start 10 tpi, the lead nut will travel one inch with two turns of the lead screw.
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How do I keep the lead screw from moving back and forth?