I pulled my Z motor off to do some maintenance and cleaning and noticed it has about .010-.012” backlash in the ball screw. The screw itself will move up and down between the thrust bearings. This does not seem normal to me, what type of adjustment is used to control the end play? Can a shim be used to take up the slack?
4 days and no response. I’m sure someone else has had the same problem. I ended up drilling and tapping the end of the ball screw, and securing it against the bearing with a button head machine screw and washer. This would have been a good idea in the first place.
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Do you have a video showing where that play is?
I found the same thing when I replaced the motor on my Z axis, I found that the location of the motor coupling half is what limited the endplay on the ball screw, not very precise to get set just right, I like your fix much better.
pat
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I really have no idea what the original plan was to captivate the screw between the bearings. The only thing had to be relying on the end brackets to do it, providing that the ball screw did not have slack between the shoulders. At least now, the ball screw is drawn up against the bottom bearing removing end play. Now as long as the bearing doesn’t move within the bottom bracket we should be ok. It would make more sense to have the bearing pressed in from the outside on both ends and then captivated with a screw on the bottom and a snap ring retainer on the top.
Anyway, it is easy to check. Just go to the bottom of the slider and put your finger on the end of the ball screw, and push up on it. If it moves up, you have end play.
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