Y Offset on 2nd Object

[czucker 0]

I'm having a very odd problem in the past 2 days.

It seems that when I print multiple objects, the first layer shifts after the brim is printed. You can see what I'm talking about in the attached photo.

The first object (right) printed just fine, but the second (left) shifted after the brim finished.

I'm printing via OctoPrint from my Raspberry Pi. . . .

I saw that people have had similar issues that may have been cleared up after reflashing firmware.

I'll give that a shot tonight, but in the meantime, anyone have any thoughts?

Best,

Chris

 

[gr5 2,269]

This is most likely a hardware issue and not a software issue. There was probably a very high acceleration between brim and part. I would mark the 6 pulleys for the Y axis but almost always it is one of the 2 pulleys on the short belt that slipped. Alternatively it could be missed steps and it *is* possible that firmware messed up but very unlikely.

You probably just have a setscrew that has worked its way loose over the years. Tighten the hell out of the motor one and the other one on the short belt. Enough so that the allen wrench twists quite a bit. But don't break your wrench.

 

[czucker 0]

No short pulleys in my setup. I went direct drive on the motors. I will check the set screws on the couplers though.

Out of curiosity, is there any reason not to use a little dab of locktite on the set screws to avoid things like this in the future?

 

[illuminarti 18]

Are you sure the fan isn't catching on the first print under some circumstances. I mean I know it got the brim down ok, but based on the photo at least, it looks like it would be pretty tight to fit the fan into the gap between the parts?

 

[czucker 0]

Are you sure the fan isn't catching on the first print under some circumstances. I mean I know it got the brim down ok, but based on the photo at least, it looks like it would be pretty tight to fit the fan into the gap between the parts?

 

Good Call! I didn't even think to check that. I never did change the print head size in the machine settings when I popped the UBIS on.

My gut tells me that this is the problem.