Gantry Blocks Seized

It’s Saturday, I’m assembling my new machine and Onefintity customer service is not working today. The gantry blocks on the Y rails will not budge. I’m not saying they move with a lot of effort. I’m saying they won’t budge. I cannot manually push the gantry rail, not will it move by jogging. Any ideas?

I believe some have found the nut at the end of the ball screw to be overtightened. I believe the washer should be able to turn slightly.

Is the controller powered on? If so, they will not move, by hand.

Thanks for replying. I do think the problem may be that the screws won’t turn. However, the nuts don’t seem to be overtightened. Also, when you refer to a washer, do you mean the bulbous shaped piece? That’s all I have directly behind the nut. I can’t tell if it turns because it’s recessed too far in to put my finger on.

Thanks for your reply. I tried powering on the controller again and doesn’t help.

I am not sure if you have seen this video but it may help:

Are you able to turn the ball screw by hand by grabbing and turning it - not powered though?

I would pull the 2 screws that hold the ball nut into the Y rail block, then see if you can freely spin the nut on the ballscrew, and then if the ballscrew will rotate. If not, it’s either too tight at the nut end, or there may be an issue with the motor being locked up. The issue is more than likely caused by something in the screw/motor assembly. It’s possible, but not probable, that the bind is caused by the linear bearings. If so, I would loosen the set screws that hold them into place. But first rule out anything to do with the motor or screw.

Edit: I just reread your original post that both appear to be seized. My response was wrongly based on my thought that it was just one side that wasn’t moving. Something else is going on with it. Hope customer service gets you squared away with it. So you can’t even move it with the motors unplugged from the controller?

Correct, neither side will move even when unplugged. Weird, huh? Someone from the support team has reached out, so hopefully we’ll get it sorted soon. I’ll provide updates. I really appreciate your help.


The support team sent me two new Y rails and got them to me quickly. Kudos to them.

Happy to hear that. Did you find out the cause of the binding, or will 1F determine that on there own?

They never said what they thought the cause was, but I assembled with the new Y rails today and they work much better. So far, they haven’t said anything about returning the original ones.

1 Like