PETG loading to nozzle malfunction
I need some help transitioning from PLA to PETG.
I figured that I would begin by loading the PETG material to the nozzle just to see if it will extrude correctly, but all that my printer does is bring the filament to the nozzle and then retract it back several times (like 6x) before it decides to move on. Then when it actually begins to "extrude the filament " the filament is actually back in the MMU2, so therefore it is not extruding anything. Then when it asks me if the printer extruded the correct color I press no but nothing happens. It seems to glitch and doesn't let me click the NO button.
any tips on printing with PETG
Can someone please help me?
RE: PETG loading to nozzle malfunction
If it starts printing even though there is no filament loaded, it is probably an issue with one or both of your filament sensors and wrong readings. Check in "support" the sensor readings and if they are correct and responsive (you can check by manually inserting filament towards each of the sensors while watching the reading). If the sensors work fine it can also be that you have too much resistence in your nozzle, ie a partial clogg. In that case flush the nozzle manually (via "move extruder" options in "settings") with some piece of filament.
PETG is softer than PLA it can be that this leads to wrong filament sensor readings in the extruder, if your tolerances are too tight. One possibility is to change the tension and thereby compression of the filament and the location of the sensor lever.
Printing PETG works fine on a well tuned MMU. But PETG can be a bit more "smeary" or messy. during changes.
Mk3s MMU2s, Voron 0.1, Voron 2.4
RE: PETG loading to nozzle malfunction
Thank you so much @thejiral. I didn't know that you could make the extruder move without actually going forward with a print. All my sensors were good, I think that when the PETG filament was going to the nozzle it was too sensitive and would just go back and forth with loading and unloading. Thank you so much again, I have been fighting with my printer for 2 days and I am glad and excited to move forward.