Crooked Z, What else should I try?

I have a Prusa-Mendel (I believe this is the i2) that was working fine, but for the last three weeks has been printing the leaning tower of Pisa. I noticed my bearings were worn so I replaced the smooth rods and bearings for both X & Y. Then I leveled the frame and hung a plumb line to make sure the Z axis was straight. Then I tightened the Y axis belt a tiny bit.

Nothing helped. Whenever I print anything the object slopes back towards the motor end of the Y axis. I can print a perfect square or circle as long as it's 1mm tall. Anything more than that will be crooked on the Z axis. Any suggestions on what else could be wrong?

Make sure your currents are set high enough so that the motor doesn't skip steps.

---

greghoge.com

HUGE 3D PRINTER PARTS SALE!!!

Yeah sounds like your y-axis is skipping steps. Might be too tight on one section of the rods. Make sure the carraige moves easily along the entire lenght.

Edited 1 time(s). Last edit at 07/23/2014 02:32PM by Rooski.

These are good suggestions. The Y-Carriage moves very smoothly since I replaced the bearings and the rods, but after reading your posts I noticed that the Y motor isn't 100% straight. It looks like the previous owner put the tension part a centimeter off from where it's supposed to be. If it's not straight there's a good chance it's binding, which would put a strain on the motor. I'm going to take apart the area that holds the motor this weekend and reassemble it so that it's perfectly straight.