Z Gantry - Can this...
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[Solved] Z Gantry - Can this be correct? How do I fix it?  


Topic starter

After suffering awful print jobs, I decided to go through the Maintenance library (calibration, valve opening etc). While doing the Level Gantry routine, I noticed (by eye) that it was not level to the bed? Following the "Manually Levelling the Z Gantry" notes and removing the Side Cover, I see this:

See attached image.

Shouldn't the nuts (highlighted top & bottom) be held in the lead-screw housing?

Can I fix this? Or has it got to go back to the workshop?


REgards, Martin

2 Answers

That is a sign of a lack of maintenance or driving the head down with the gantry out of level. The dust and dirt of every day use builds up on the Z screws and must be cleaned and the lubricant replaced periodically per the maintenance instructions in the help section of the CEL website. 

I suggest that you open a support ticket to get the instructions to repair the issue after you have cleaned it. This will also help ensure you have a contact established in the event that you need to purchase a replacement Z drive due to damage.

Topic starter
Posted by: @bhudson

That is a sign of a lack of maintenance....

After only ~100hours use?

The only way I can see that the (spring loaded) nuts can drift apart, as seen in the image, is if they were not in the Z-Screw housing from the start?

However, as the saying goes: "There's always a silver...". While refitting the Z-Nuts, I noted that the two (LM6UU) bearing were completely shot! Two new bearings fitted and walla.... Solved a long standing issue: See "What is happening here?"


Regards, Martin

@mprowe I have seen bearings and nuts damaged very quickly by running the printer in very dirty conditions. It may be that the bearings were defective, but you shouldn't see both of them fail and the screw fail on one side without some external cause. I would still be looking into a problem with cleaning and lubrication or some head crash to cause the problem.


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