TAZ5 - Z axis steppers move at different rates?

Hi,

I recently got a TAZ5 and am super pleased with it. I spent a bunch of time leveling the bed and my first prints have come out well. I noticed though that for every ~20 hours of printing, the bed becomes out of level by ~1/2mm. The whole right side of the bed will be further away from the extruder, while the left side is fine. I suspect that the right-most Z-axis stepper motor may be moving a hair slower than the left one, causing the issue. I can re-level the bed prior to every print by manually turning the right-most z-axis rod/screw. Wasn’t sure if anybody else has experienced this issue or has any advice.

Thanks in advance
-Justin

Check that the small sets crews on the couplers are tight, at least one is on the flat spot of the leadscrew and motor shafts, and both of them on both sides are still there. Sometimes they work loose or fall out.

I don’t think the steppers are moving at different rates… I’d attribute the change in bed level to removal of parts. Specifically, the corners of the bed can “catching” against the bed leveling adjustment screw when accidentally pressing on the bed to remove parts. Treat this as a sign to re-level the bed. :slight_smile:

Thanks - I thought about this, but when I first realized the problem (after a bunch of failed prints), I noticed the bed was almost a whole centimeter out of level, and the whole right side was the issue. There’s no way it’s the bed adjustment screws.

I’ll check the set screws. If it’s not that, I just thought of a small experiment I can run though that will help quantify the problem and prove it’s not the set screws. I’ll plan on moving the z-axis up and down in fixed increments (e.g. 100mm up, 100mm back down) and then measure the gap between the extruder nozzle and the bed each time. If I see no difference after a bunch of movement, it must be something I’m doing. Otherwise, there is something wrong.

OK, so I don’t see any difference after moving the z-axis up and down a bunch. I’m wondering if the printer got bumped at one point or something, but it has happened a couple of times. I’ll keep an eye out as I remove parts, but I’ve done all but a few of my prints overnight and by the time I remove them in the morning, the bed has been cool for several hours and I can just pick them up.