Getting lines and seperation in my prints.

[spenter 0]

I purchased and assembled a Ulimaker Original + kit. Go it working after a few hiccups.

The big problem now is that I getting visible lines in my prints (100 microns) and occasional separation at the lines.

These lines have always been at the same height. UM support has not figured it out. The suggested going up on nozzle temp and down on print speed. Worked for a while until I changed filament.

I re-did the z axis bearing seating procedure and the line seems to have moved up just a little but is still there.

This is my third kit I have built. The previous two were from China and you get what you pay for sure held true. I expected a lot better from this printer. I think this can be a great printer once I get this straightened out but it sure needs some help.

Any one else expereaince this or have any ideas?

[tomnagel 79]

My suspicion goes to the z-bearings. If you decouple the spindle from the bed, or at least the z-motor from the spindle, does the bed move smoothly? Without points where it feels like there's sand in the bearings?

Such friction points in the z-bearings can hold the bed at a certain position while printing. It just hangs there for 2-3 layers, until the play between spindle and nut runs out, so that the bed is forced past this friction point. Since it then drops multiple layers, the next layer that is printed looks underextruded, and may cause separation as you describe.