I am at my wits’ end. I’ve tried everything I could to prevent the z axis jamming and everything I tried that could make it work either seems to result in having the left side missing steps/microjamming and messing the z height (usually by not going up enough and therefore skewing the whole x gantry left-low/right-high).
Here’s what I tried:
loosening the x carriage’s rods until they turn free, manually setting the x gantry level to the top of the frame, re-setting the stepper motor’s unions to their leadscrews, dismantling the whole machine and remounting it exactly according to the specs and info on the ohai webpage, running the z axis with everything that can be loose loose, replacing the steppers, replacing the mainboard… I have no idea what causes this and why it continues like so.
It was a free printer and I can guess why the previous person decided it was enough…
Ouch. Can’t speak to your situation. Sounds like an initial leveling problem. Occasionally, my Taz 6 z-axis rods get out of level since they are not mechanically connected. After cleaning the nozzle & heatbed, I use machinist 1-2-3 inch blocks to check for mis-alignment using the direct connection lead from computer to printer to make movements with the cura le software monitor manual printer control console. Starting with the nozzle all the way to the left, adjust the height to the 1” side just fits between the nozzle tip and the heatbed. Next using the console X axis movement, slide the nozzle all the way to the right side and repeat using the block. If they do not feel the same slightly touch, they require adjustment. At this stage, TURN THE PRINTER OFF. With the printer off and working on both sides, manually turn the Z axis leadscrews to move up or down. This requires manually sliding the nozzle left & right between adjusting the leadscrews. Turning the leadscrews is done in small increments and realizing turning 1 adjusts both sides. Again, a clean nozzle and heatbed are crucial. Once happy, turn the printer ON. The leadscrew timing should now be aligned. While on and controlling movement from the console, reset the nozzle height to fit the 1” side of the block on both sides to check your work. When happy, use the console’s Z axis control to move up 25.4mm exactly. The movement should be exactly 1” higher. Again, use the block on the 2” side & check nozzle clearance. This will check if the Z axis screws are in alignment and show any wear the mating parts may have. Check the clearance at the 2” level, then repeat Z movement up 25.4mm. Check with 3” side of block clearance. Repeat movement again, only in the down (-25.4mm) to the 2” and 1” positions.
Please understand, this method works well while the printer is level flat in frame as well as heatbed and the frane is as square as can be had. Refer to instructions as to how to align & level the printer. This method can be used to assure Y axis rails are squared to the frame. If a Z nut is worn, it will show up as inconsistant movement on one or both sides. If squeeking, lubricate.
Have you tried to square the frame, here are the instructions OHAI: Open Hardware Assembly Instructions