RE: Layer Shift Wall of Shame
... and please add comments with each print whether you had "avoid crossing perimeters" enabled. 🙄
RE:
... or loose belts ... or the part warped ... or ...
- Bob Marley
RE: Layer Shift Wall of Shame
#1 - first rodeo with layer shift, so makes sense that I would rely on default settings. Real question is, if it should be turned on, why isn't this the default?
#3 - avoid crossing perimeters enabled
#4 - avoid crossing perimeters enabled
#5 - avoid crossing perimeters enabled
... and please add comments with each print whether you had "avoid crossing perimeters" enabled. 🙄
RE: Layer Shift Wall of Shame
#1-#3 wasn't aware
#4-#5 Belt tensioned per app. As admitted in this thread, it appears the Core One seems to be a finicky in this area.
Part warpage? I do my best to avoid that as well:
Indoor setting, temperature controlled environment
Thorough isopropyl alcohol (90%) cleaning, every build, no exceptions (some have recently suggested soap/water rinse which I have done as well, just not every build)
Nozzle cleaning, every build, no exceptions
Use almost exclusively Prusament filament (have one Kexcelled roll that was a specific color, no issues with that so far)
Try to control filament humidity with Polymaker dryboxes, seal bags for storage, etc. (admittedly the Polymaker boxes/dryer don't do that well, and currently looking for other solutions)
Then there's been the suggestions around slowing down speed & feeds, acceleration values, etc. All welcomed tips and suggestions, just nothing so far that has guaranteed that it won't happen again. Will keep refining the process until I find something that works more reliably. Appreciate the input.
... or loose belts ... or the part warped ... or ...
RE: Layer Shift Wall of Shame
If I'm not mistaken, "Avoid Crossing Perimeters" is off by default. It should remain off since its the cause of many layer shift issues. I only experienced layer shifts early on when I didn't fully understand how the belts should be tensioned. Another time when umbilical sagged and wedged between the printhead and the X motor around (0,220) etc.
- Bob Marley
RE: Layer Shift Wall of Shame
This helped, thanks. I found the original thread where this was mentioned...and forgot about the part where this was in combination with Stealth Mode.
https://forum.prusa3d.com/forum/postid/754692/
So, I can see how I misinterpreted as it needing to be turned on. I'll try again.
RE:
... Another time when umbilical sagged and wedged between the printhead and the X motor around (0,220) etc.
Very good point ... I'm even starting to wonder whether my printer is missing a part.
The picture is from the assembly instructions. Support of the umbilical ("swing arm assembly") ends at the right end (!) of the green marks in the picture.
And yes, the cable always drops down and would get stuck between print head and left stepper motor if moving to the back left corner. Maybe it holds at room temperature, but chamber temperature during operation is higher so the cable softens and sags.
How should this cable be kept above the stepper motor level reliably?
RE: Layer Shift Wall of Shame
This is what I use: Core One modified "bowden-bend" with wider radius with the Bowden tube on top, it acts a rigid spine and lifts it up enough that I needn't worry about sag (as much). I found that it also makes it slightly easier to get filaments into the extruder.
How should this cable be kept above the stepper motor level reliably?
- Bob Marley
RE:
Right... I'm using the "PTFE tube clip" that came with the MMU, which attaches the tube horizontally (as the MMU brings its own filament tube).
So the PTFE tube does not support the umbilical at all, as in the non-MMU stock version. This is, IMHO, a design flaw for the "Core One with enclosed MMU" product: It seems they just forgot that the original PTFE tube is lifting the umbilical a little.
RE: Layer Shift Wall of Shame
If I'm not mistaken, "Avoid Crossing Perimeters" is off by default. It should remain off since its the cause of many layer shift issues. .
Thanks for clarifying. Yes, that's what I meant in my post above: It is known that the "avoid crossing perimeters" mode causes the slicer to generate Gcode with impossibly rapid movements, but I don't think Prusa has officially acknowledged (let alone fixed) this issue. Hence many users still fall into this trap, and it is probably the root cause behind a significant percentage of the layer shifts that are encountered.







