Failures at the same height with every model

I’ve had my Ender 3 Neo for a few weeks now and it was working beautifully up until about two weeks ago. All prints, regardless of model or slicer, fail between 10-15mm. My latest two failed after only a few layers.

I have completely disassembled and reassembled the machine to make sure nothing was loose. I’ve used two different slicers just to make sure it wasn’t a problem with the gcode. The bed and z-offset are good. Leveling test prints come out fine, adhere beautifully, and first layers are smooth everywhere on the bed. Filament feeds from a dryer, which is almost always running. Changing filament brands hasn’t helped.

I think there may be a mechanical problem, but I can’t find it. I have to redo the z-offset after every print because it changes. Sometimes the changes are significant. For example, I would set the offset to -02.100, but when I redo it after a print, it’ll be something like -01.85. Next time around, it’ll be -01.98. I also have to wait about ten seconds after changing the offset because the nozzle continues to drop after it’s set. One moment the paper slides without resistance, but a moment later with no changes made, the paper is pinned to the bed.

People, I’m getting desperate. I have had one successful print in the last two weeks.

Hi @crankysaint and welcome to the forums.

It sounds like your gantry is loose if it is lowering on its own. Check the lead screw and stepper motor on the Z axis and make sure that nothing is loose. You might find that the coupler is not fully tightened.

Hi @crankysaint,

As @Nikoli commented, I can confirm this is the Z axis bearings being to tight in one of the sides. Remember to not leaving them too loose or too tight.

Loosened the gantry a little. It worked. Thanks, folks. Much appreciated.


That print looks great! Glad to hear its printing well now :slight_smile: