XY shifting midprint with no apparent reason?
Printing with SUNLU ASA, ususlly with no problems. This time it seems like XY shifted mid-print, so layers are moved from their required position. Havent caught this in time, so i am not sure if there was something mechanical, or motors losing their steps... Did anyone encounter such issue? What can i do to avoid this? Both print were with a little tweaked settings, right one printed even with 75% speed, as i thought maybe acceleration was to fast.
RE: XY shifting midprint with no apparent reason?
It is very likely due to step loss in one motor -- if a single motor misses (part of) a movement, you will get a diagonal displacement. This could be due to a mechanical collision, e.g. if the print has detached and is warping upwards in one corner. But the most common cause is actually a software bug in PrusaSlicer:
In Print Settings > Layers and Perimeters > Quality, do you have Avoid Crossing Perimeters enabled by any chance? That setting may generate Gcode with sporadic "impossible" moves, with extreme accelerations and speeds. Simply disabling this option should then result in Gcode that prints reliably.
Make sure your build sheet is thoroughly clean - look up threads here on the topic.
Cheerio,
RE: XY shifting midprint with no apparent reason?
A myriad of possible issues. The "avoid crossing perimeters" bug mentioned by Jurgen is certainly something to check for even. But I'm more in camp Diem, my first suspect is always lack of adhesion to the print bed. If your sheets are clean, a common cause I noticed, particularly, with ASA is a tiny bit of material sticking to the nozzle during the mesh bed leveling process. Not enough to fail the nozzle cleaning process but enough to screw up the first layer. May not manifest itself right away but after a 1 cm or so of printing. Could also be warped corners or curling overhangs. If I run into an inexplicable layer shift and I don't have time or desire to troubleshoot it (which is like, always), I usually just slap some Layerneer bed weld on, which more often than not does the job and I can get on with life.
Formerly known on this forum as @fuchsr -- https://foxrun3d.com/
RE: XY shifting midprint with no apparent reason?
A myriad of possible issues. The "avoid crossing perimeters" bug mentioned by Jurgen is certainly something to check for even. But I'm more in camp Diem, my first suspect is always lack of adhesion to the print bed.
I did not rule out that possible physical cause -- actually mentioned it as the first possibility in my reply. Given that the part is a largish, solid plate, warping might well be an issue. But checking whether "avoid crossing parameters" is enabled takes no time at all, and might avoid lengthy printing attempts and misprints. So I would always start there.
RE: XY shifting midprint with no apparent reason?
Avoid crossing perimeters is disabled. Bed is clean, with glue, but most of that part is on supports due to something sticking out on the other side. But it doesn't seem that the part lifted. Nozzle is clean. I will try to print it upside down to check if that lifting is a problem. In PLA test print everything went smoothly...