1 Topic by johnforeman

  • johnforeman
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Topic: totally screwed up my calibration!!

well, i spent last weekend getting my new SD3 dialed in and then was gone all week.  So today i start printing out a thingverse filament spool holder and the filament got in a bind while i was away from the printer.  needless to say, the print was ruined and now my calibration is crap.  actually i think it's worse than what it was out of the box.
after calibration after filament bind picture.  the one on the left is after i 'crashed' the printer.  looks like i messed up the xy.  guess it's time to start over..
oh well, i guess that's why we do this stuff.. lol

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2 Reply by IanJohnson

  • IanJohnson
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Re: totally screwed up my calibration!!

That is Y backlash. Maybe the alignment messed up just a bit so it is harder to move the Y axis.  You could try turning off the motors and sliding it forward and back a few times by hand. If that doesn't help, look for the True Circles Calbration video Solidoodle posted to Vimeo.

3 Reply by johnforeman

  • johnforeman
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Re: totally screwed up my calibration!!

IanJohnson wrote:

That is Y backlash. Maybe the alignment messed up just a bit so it is harder to move the Y axis.  You could try turning off the motors and sliding it forward and back a few times by hand. If that doesn't help, look for the True Circles Calbration video Solidoodle posted to Vimeo.

that's what i did.  got it close enough to keep printing the filament spool.  it's not as good as i had it, but it will do for now.  when i was adjusting the axis, i noticed the carrier pulley's were floating in both directions quite a bit.  Any idea what adjustments to make to get that out?

4 Reply by Briggs

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Re: totally screwed up my calibration!!

This is a very common problem. The solution is what Ian said, plus tightening up your y-stepper to drive shaft belt, the little short one. These are MXL belts, so there is some slop. To minimize, tighten belt tight. Too tight, however, and you bend the drive shaft. Some users have added pillow block bearings to prevent the shaft from bending. My guess is that if you held the drive shaft with one hand, and turned the stepper motor pulley with your other, you would see first hand the backlash slop I'm talking about.