Problem:
During the start g-code the nozzle is cool during bed level. Nozzle heats up before print area scan. When the print area is large the nozzle starts oozing filament during the process. Its not an issue with smaller prints becauae not as much is scanned. This issue happens regardless of shutting off bed level or flow calabration.
Solution:
Either scan the build plate before all the other start g-code processes or at least wait till 50% of the scan is done before heating nozzle.
Also it would be smart to put the qr scan BEFORE the whole start up process instead of at the end.
2 Likes
I have noticed this too. Cause blobs on the nozzle and even the wiper doesn’t get them off. I use ABS, but I couldn’t imagine what it would be like with PETG.
1 Like
I just noticed this with petg. It oozes like crazy for prints with large bed coverage (e.g. the filament spool). Waiting for 50% wouldn’t do it either in such cases. Wait until a small, fixed amount of time is left.
Please fix this ASAP.
Related is that the gcode doesn’t wait long enough for the nozzle to cool down before starting the first layer scan for PETG. It starts scanning almost immediately even if the nozzle has only dropped 20 degrees and a large blob of petg will form AFTER the wiping that will often trash parts of a pristine first layer. I’m guessing the code is waiting for a fixed temperature delta as opposed to a fixed threshold temperature which may be fine for lower temps like PLA, but for PETG it isn’t sufficient.