RE: PETG Fails Nozzle Cleaning every time.
This worked for me too. To make it automatic without having to turn the knob, I modified the ;START G-CODE section in the Prusa Slicer Printer Settings. Replaced code between lines M83 ; extruder relative mode and M84 E ; turn off E motor with:
;*********
;* BEGIN * Set HotEnd Temp for Nozzle Cleaning Cycle and Bed levelling (MCB)
;********* - Changed PET temp from 195 to 215
M104 T0 S{((filament_type[0] == "PC" or filament_type[0] == "PA") ? (first_layer_temperature[0] - 25) : (filament_type[0] == "FLEX" ? 210 : (filament_type[0]=~/.*PET.*/ ? 215 : 170)))} ; set extruder temp for bed levelling
M109 T0 R{((filament_type[0] == "PC" or filament_type[0] == "PA") ? (first_layer_temperature[0] - 25) : (filament_type[0] == "FLEX" ? 210 : (filament_type[0]=~/.*PET.*/ ? 215 : 170)))} ; wait for temp
;********
;* END *
;********
I am using Prusa Slicer Version 2.7.4+win64.
ZZTOP: RE: PETG Fails Nozzle Cleaning every time.
Hello ZZTOP,
thanks for your gcode. After inserting it into the Start G-Code section, it now works (more often than before). It is a huge step forward. Thanks again!
With best regards,
TJ
RE: PETG Fails Nozzle Cleaning every time.
TJ,
Im glad it helped!
My thinking on why this works is that the problem seems to occur when filament is oozing out of the nozzle during the nozzle cleaning phase, interfering with the load cell readings. So I did a test print without any filament loaded plus a 'clean' nozzle. The nozzle cleaning worked perfectly along with the bedleveling phase too. Of course I aborted the print before the print progressed any further. I tried this test many times, always getting the same good result.
Based on this and using Sunlu PETG I determined that 170c was just about the right nozzle temp without it oozing. So for the nozzle cleaning and bedleveling phase I set it to 170c and then 230c before the print started. These settings have been working great for me.
I assume this process would work for any filament? I haven't tried PLA or TPU yet with this approach yet, but I think it has a good chance of working.
Let me know if your results turn out like mine.
Thanks.