x/y seems to be off, but I'm not hearing any skipped steps

joeauthentise · October 7, 2014

I have a Ultimaker original, and I have all the relevant settings set in Cura, but the x & y axis seem to be off when it comes to infills, and sometimes curves. Anyone know the fix to this?

gr5 · October 7, 2014

Those holes are partly created by underextrusion which you can fix by printing a little hotter or a little slower (e.g. 50mm/sec .2mm layers 240C should be fine) or you can try tightening the screw on the feeder. My spring is compressed down to 11mm if that helps although I think that isn't helpful as the feeder design has changed a bit I think and it might not be the same spring.

ALSO I agree that you have some X/Y error. It's caused by "backlash" also known as "play". Backlash can be caused by loose belts or very high friction. In the case of loose belts, the head never moves as far as the stepper commands it in either X, Y or both. In the case of high friction, the head also never moves as far as commanded because even though the belt is tight the head doesn't move that last .2mm because static friction holds it in place.

So push the head around in X and Y. If you push with the side blocks you should be able to push the head with one finger on each side block. X and Y friction should be similar. Put some oil on all 6 of the rods in the gantry system. Any light oil will do. More likely though the problem is the belts are too loose. Start with the X and Y short belts. Push the motors down quite firmly. The longer belts are trickier to tighten. I recommend using the metal part of a clothes pin and using that to tighten the long belts. Google it. More info about the relationship of loose belts to print quality results here (posts #7 and #8 - look at picture in post 7 and read the text connected to that photo - you have to click on the photo first and then the phenomenon is explained better in post #8):

http://umforum.ultimaker.com/index.php?/topic/1872-some-calibration-photographs/?p=14396