0.6mm HF nozzle first layer lines are too fine on textured sheet
I am running an MK4s upgraded from a factory build MK4. This issue was also seem using standard flow 0.6mm nozzle on MK4 with textured sheet.
I am using the 0.6mm HF nozzle on the MK4S, printing PETG using these settings; everything is stock in the printer and filament settings:
Filament is Black Overture PETG; I have also tried with Polymaker colored PETG.
It looks like the first layer calibration using the load cell is not working properly on the textured sheet. As you can see the layer lines are far too thin.
I can get the first layer to turn out fine if I bump up the extruder temperature to 210 for PETG before the bed leveling takes place as below:
M140 S[first_layer_bed_temperature] ; set bed temp
M104 T0 S{((filament_notes[0]=~/.*HT_MBL10.*/) ? (first_layer_temperature[0] - 10) : (filament_type[0] == "PC" or filament_type[0] == "PA") ? (first_layer_temperature[0] - 25) : (filament_type[0] == "FLEX") ? 210 : (filament_type[0]=~/.*PET.*/) ? 230 : 170)} ; set extruder temp for bed leveling
M109 T0 R{((filament_notes[0]=~/.*HT_MBL10.*/) ? (first_layer_temperature[0] - 10) : (filament_type[0] == "PC" or filament_type[0] == "PA") ? (first_layer_temperature[0] - 25) : (filament_type[0] == "FLEX") ? 210 : (filament_type[0]=~/.*PET.*/) ? 230 : 170)} ; wait for temp
As shown before, the first layer looks much better with enough "squish" for a good first layer:
The problem is this leaves dots of petg at all the probing points which can be hard to scrape off. Nozzle cleaning also fails often because of this.
Would appreciate some thoughts on next steps here.
RE: 0.6mm HF nozzle first layer lines are too fine on textured sheet
I think this is related to
https://github.com/prusa3d/Prusa-Firmware-Buddy/issues/4254
I don't use 0.6 nozzles or HF nozzles but I routinely have to adjust live Z on my Mk4S's manually when the print starts. For PLA, I have to go up, for PETG down. Go figure. But it's pretty much never "always perfect". Maybe on smooth sheets, but I haven't used those in years.
Formerly known on this forum as @fuchsr -- until all hell broke loose with the forum software...
RE: 0.6mm HF nozzle first layer lines are too fine on textured sheet
I think this is related to
https://github.com/prusa3d/Prusa-Firmware-Buddy/issues/4254
I don't use 0.6 nozzles or HF nozzles but I routinely have to adjust live Z on my Mk4S's manually when the print starts. For PLA, I have to go up, for PETG down. Go figure. But it's pretty much never "always perfect". Maybe on smooth sheets, but I haven't used those in years.
Agree, I think this is the same issue. Setting the live Z to -0.07mm while the print starts solved the problem entirely.
Given the fact that the probing at 230 mitigates the issue it seems like there is some residue left on the nozzle that the cleaning step doesn't get. However, compensating for the bad probing with Z offset is another solution I guess.;
Thanks!
RE: 0.6mm HF nozzle first layer lines are too fine on textured sheet
I'm also unable to get reliable first layers on the regular flexible sheet. As you can see the first layer Z offset is too high.
This Prusa MK4S is FAR less reliable at printing PETG than my MK3S+ was. Sure it is fast, but enough prints get ruined that I'm wondering if it is even worth trying to print PETG on this printer.
RE: 0.6mm HF nozzle first layer lines are too fine on textured sheet
I think the problem is that there is filament leftover from the last print. If I scrub down the nozzle I don't need the extra temp trick. Just a huge pain to have to do that though.
RE:
I have reached out to Prusa support but after 3 weeks of back and forth I don't feel we are converging on an answer. I'm pretty bummed because I love my MK3S+ and was stoked to get higher print speeds. However my Mk3s+ is running circles around my Mk4s because I can don't have to spend so much time futzing with it.
I kinda wish I could get an Mk4s to mk3s+ downgrade kit. Hah.
RE: 0.6mm HF nozzle first layer lines are too fine on textured sheet
I think the problem is that there is filament leftover from the last print. If I scrub down the nozzle I don't need the extra temp trick. Just a huge pain to have to do that though.
I've never had problems of PETG build-up on the nozzle causing bed leveling probing to fail, thus causing prints to fail. I keep my nozzles clean, and that usually just entails taking 3-4 seconds to remove any oozing filament that's on the nozzle after a print finishes. Sometimes there's PETG build-up on the side of the nozzle that you really should remove, but that wouldn't affect the probing and bed leveling process.
I assume you've already thought about this, but on the off chance that you haven't, maybe this would help. (I print 95% of all my prints on the satin sheet but I don't think that would make a difference with this specific problem)
RE: 0.6mm HF nozzle first layer lines are too fine on textured sheet
. Sure it is fast, but enough prints get ruined that I'm wondering if it i
I have it working quite reliably now. When the print starts I adjust live z by -0.04.
It's crazy. I have to adjust PETG and ASA down but PLA *UP* by +0.04.
my Mk3S were set and go. My MkS need babysitting. And at the same time my XL is going fine without adjustments. Go figure.
Formerly known on this forum as @fuchsr -- until all hell broke loose with the forum software...
RE: 0.6mm HF nozzle first layer lines are too fine on textured sheet
I think the problem is that there is filament leftover from the last print. If I scrub down the nozzle I don't need the extra temp trick. Just a huge pain to have to do that though.
I've never had problems of PETG build-up on the nozzle causing bed leveling probing to fail, thus causing prints to fail. I keep my nozzles clean, and that usually just entails taking 3-4 seconds to remove any oozing filament that's on the nozzle after a print finishes. Sometimes there's PETG build-up on the side of the nozzle that you really should remove, but that wouldn't affect the probing and bed leveling process.
I assume you've already thought about this, but on the off chance that you haven't, maybe this would help. (I print 95% of all my prints on the satin sheet but I don't think that would make a difference with this specific problem)
Out of curiosity what do you use to clean the nozzle? I have been using a wire brush but wonder if I'm perhaps being yo aggressive.
After more testing even if I do clean the nozzle I still find it unreliable. Sometimes it works and sometimes it doesn't.
RE: 0.6mm HF nozzle first layer lines are too fine on textured sheet
. Sure it is fast, but enough prints get ruined that I'm wondering if it i
I have it working quite reliably now. When the print starts I adjust live z by -0.04.
It's crazy. I have to adjust PETG and ASA down but PLA *UP* by +0.04.
my Mk3S were set and go. My MkS need babysitting. And at the same time my XL is going fine without adjustments. Go figure.
Yeah if I adjust the live z it's pretty consistent. My problem is I use these printers for a lot of repetitive prints. With the mk3s+ I can pop into the garage and clear the build plate in a few min. With the mk4s+ I have to sit and babysit the start of the print so I end up getting less jobs in aggregate.
RE: 0.6mm HF nozzle first layer lines are too fine on textured sheet
That about sums it up. I'm actually glad I kept a Mk3.5 around. It just works.
Formerly known on this forum as @fuchsr -- until all hell broke loose with the forum software...