X-Axis seems to shift while building object

I am having some issues with the x-axis shifting slightly to the left during a build. Sometimes this happens in the first few layers and sometimes it happens later in the build, which then ruins the part if there are screw holes or anything that needs to be straight. Has anyone run into this issue before?? If so, what could be going on?

Hi,

One thing I would check is whether the X pulley is slipping or not, and whether the belt is tight enough (but not too tight).

Have you flattened the shaft of the stepper motor?

Cheers,
Gary

Edited 1 time(s). Last edit at 09/08/2011 04:27AM by garyhodgson.

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I had this problem (non-mendel build), it appeared after adding weight (AL plate) to the carriage, turned out to be lost steps in the X motor. Slightly increased the driver's current and added a fan pointed to the culprit stepper (this one: [www.zappautomation.co.uk], I prefer the 1684 , problem solved.

There are a number of different things that can cause this. I had it happen myself recently and it turned out that my heat bed was too hot. I was printing PLA with a heat bed temperature of around 70 degrees C and it was enough to cause the lower layers of plastic to soften enough to shift over slightly.

Another possibility is a problem with your z axis i.e. your entire x axis is shifting back and forth due to loose parts etc. Or it could be your heat bed shifting (is the glass plate secure?). Or your hot end might not be properly secure as a result of it or its mounting bolts expanding due to the heat, and it's tilting back and forth. Or your x endstop might be shifting when the x-carriage hits it (unlikely though, you'd eventually expect it to stop). Or if your heat bed plate is thin and isn't regulated properly then it might be expanding and contracting throughout the course of a print.

Point being, there are many possible culprits and your best bet would be to first determine whether the problem is due to the print bed shifting or the extruder nozzle and then work back from there. To be honest though I think Lanthan's suggestion of lost steps is probably the most likely cause.

I think I found the issue. I secured the pulley on my x-axis motor and it seems to have gone away.

thanks for the help!

I had this issue too and in my case it was because I got lazy / thought I could avoid flattening the stepper motor shaft. After fixing this and really tightening on the gears, I haven't had an issue.