Shifting

[bray.christopher]

We have an Ultimaker 2 Extended. It usually prints GREAT, but it is shifting when printing this part.

The material is Semi-Flex.





Here are the settings I used.



Then I tried to print it again. I slowed the print speed down to 1300 mm/min.



And still, the print shifted at the same height! But it did shift a little more than the last time.

At first I thought this was a machine problem, now I think it is a slicer problem since the shift is happening at the same height.

And yes, the print previews looked fine. I always check the preview for weird things.

Anybody have any ideas?

[Heutinck]

Check your gcode to see if its actually SD3 or the printer that is shifting the print.

[nexusdb]

I have the same problem here.

How do I check the GCode?

I have checked the Preview Screen from all Angles and cant see any issues, just like bray.christopher stated in his post.

[dkightley]

BC

You have your X/Y axis movement speed set at 6000mm/min. This is probably what is causing the stepper motor to either jump the belt or fail to move fully...which is what I think is happening.

Have a look at the build in preview mode and set it to view movement speeds with travel moves shown. Take a look at the travel moves. Are there any at the point of the skip in the same direction of the skip?? If so...then this may indicate the conditions for the mechanical glitch.

Slowing the movement speed down may be all that is needed.....

[bray.christopher]

After much trouble shooting, I think I have decided that this was a hardware problem.

After printing two more successful PLA prints and another (different model) Semi-Flex print... the printer completely freaked out.

The printer started clicking like crazy. Not stepper clicks. The belt was skipping. I killed the print, but it was still trying to home the head and the belt was still skipping, so I had to kill the power.

The rear "X" linear rod was sticky in the middle of it. I have no idea why. I should probably stop eating cotton candy around the printer.

I wiped down all of the linear rods with acetone and then applied a bit of sewing machine oil.

This might be completely unrelated. I doesn't make any sense that this problem would have caused two 36 hour prints to glitch at the same height. But whatever.

Thanks for the ideas.

[wirlybird]

Don't know if this will mean anything or not but I was talking to someone who was having a long print blow up at the same exact point each time (S3D was used). They ended up rotating the object about 5 degrees on the bed (like clockwise) and it solved the problem.

[CompoundCarl]

They have a page about this issue: https://www.simplify3d.com/support/prin ... salignment

Definitely sounds like mechanical issues or moving too fast are the common causes

[bray.christopher]

Don't know if this will mean anything or not but I was talking to someone who was having a long print blow up at the same exact point each time (S3D was used). They ended up rotating the object about 5 degrees on the bed (like clockwise) and it solved the problem.

Crazy. But I believe it.