1 Topic by Skyminer

  • Skyminer
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Topic: Z axis calibration?

I've discovered a problem with my printing.  Imagine a cylinder, sliced in half, laying with the flat (sliced face) on the tray.  When printing it, things get squashed in the Z axis.. It doesn't turn out to be a half circle, but rather more of a squashed half circle.  It starts the right width, but seems to go out of wack as it works it's way up the curve.

This recently became apparent for be when I was trying to mate parts together.  The cylinder I was able to print standing up was perfect.. The one I had to cut in half and lay down wasn't.

Thoughts?

2 Reply by Tomek

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Re: Z axis calibration?

(1) Sounds like you have your circles calibrated, nice.

(2) It's unusual for Z axis to need calibration on the E-steps. I think it'd be a good idea to print something easily measured with calipers (a round object is not ideal.) So like a 50mm tall box mostly hollow infill of course, and then measure how close it is to 50mm.  This might tell you more about your situation.

3 Reply by Skyminer

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Re: Z axis calibration?

Ok, so here's what I've found.

I double checked that the things I've been trying were modeled and sliced correctly.  When I re-assemble the modeled bits, they are a proper circle.

I printed a 25mmx25mmx25mm calibration cube.  X and Y are both about 25.05mm, and Z is 24.43.

When I look at the printed cylinder thing though, it looks like it's probably squashed about a mm or two on each half preventing it from being a proper circle.

4 Reply by doppler

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Re: Z axis calibration?

Skyminer wrote:

Ok, so here's what I've found.

I double checked that the things I've been trying were modeled and sliced correctly.  When I re-assemble the modeled bits, they are a proper circle.

I printed a 25mmx25mmx25mm calibration cube.  X and Y are both about 25.05mm, and Z is 24.43.

When I look at the printed cylinder thing though, it looks like it's probably squashed about a mm or two on each half preventing it from being a proper circle.

Is it possible that your squash is due to the first layer, which we all squash to get good part adhesion to the bed.  A mm would be too much for this, and your z being 24.43 probably needs a little e-step tuning, if the filament is filling in everything properly.

Andrew