RE: Nozzle cleaning consistently fails with PETG
No, you change the default gcode in PrusaSlicer. Then that'll get included in every gcode file.
Okay, I'm going to see how @trantako's wiring changes do for a while. If reliability doesn't improve, I'll look into the gcode changes.
Thanks
RE: Nozzle cleaning consistently fails with PETG
@trantako's wire routing changes appear to have resolved the nozzle cleaning issue for me--I haven't had a single startup error since making that simple adjustment. Woot! Thanks, man!
I upgraded my mk4s in June and am finally able to use this thing without getting frustrated at it. I've never had any issues with previous Prusa printers (mk3s, 3.5s, 4, and 4s) so I was extremely disappointed in the Core One's performance up to this point. Some kind of note needs to be added to the kit/upgrade instructions so folks are at least aware of a potential problem and how to fix it.
RE:
Some kind of note needs to be added to the kit/upgrade instructions so folks are at least aware of a potential problem and how to fix it.
The notes are there in the build instructions as user comments. I built my kit end of June at a time when most of these bugs were still being worked out (by users of course and not Prusa). Anyway, in hindsight, it's quite obvious (at least to me) that Prusa rushed to get the Core One out-the-door before they became irrelevant. Just like 4-5 years ago, when every one copied the Creality Ender (except Prusa), every one now is copying Bambu (except Prusa). Let's hope they stay relevant with the INDX system.
RE: Nozzle cleaning consistently fails with PETG
I have n't had the problem with PETG, only with PCBlend. My solution: change the "-25" in the custom Gcode start section to "-50" (there are two of these lines).
Not a single problem after that (the same issue I had with my mk4s that was solved in the same way).
M109 R{((filament_notes[0]=~/.*MBL160.*/) ? 160 : (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 : 170)} ; wait for temp
Just for the fun of it I also installed, much later, a nozzle cleaning pad. Works as expected, no strage goo on the plate.
RE: Nozzle cleaning consistently fails with PETG
I have n't had the problem with PETG, only with PCBlend. My solution: change the "-25" in the custom Gcode start section to "-50" (there are two of these lines).
Not a single problem after that (the same issue I had with my mk4s that was solved in the same way).
M109 R{((filament_notes[0]=~/.*MBL160.*/) ? 160 : (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 : 170)} ; wait for tempJust for the fun of it I also installed, much later, a nozzle cleaning pad. Works as expected, no strage goo on the plate.
As an aside, really wish Prusa would allow/implement nested if/then/else macros. The compound ternary operators are hard mentally to parse.
RE: Nozzle cleaning consistently fails with PETG
... indeed, or case statements... whatever makes that ugly thing read better 😀
I have n't had the problem with PETG, only with PCBlend. My solution: change the "-25" in the custom Gcode start section to "-50" (there are two of these lines).
Not a single problem after that (the same issue I had with my mk4s that was solved in the same way).
M109 R{((filament_notes[0]=~/.*MBL160.*/) ? 160 : (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 : 170)} ; wait for tempJust for the fun of it I also installed, much later, a nozzle cleaning pad. Works as expected, no strage goo on the plate.
As an aside, really wish Prusa would allow/implement nested if/then/else macros. The compound ternary operators are hard mentally to parse.
RE: Nozzle cleaning consistently fails with PETG
What is this "nozzle cleaning" procedure needed for in the first place? I'd say it's the most annoying feature with Prusa printers, and now you can never be sure if your printing work will succeed or not. With my C1 and PETG it can occur multiple times in a row, and has made my 3D printing everyting than a smooth experience. Imagine starting a 20-hour job and coming a day later just to see nothing has been printed. Or not being able to just start a job and go away but you need to wait 5-10 mins to see if the cleaning routine succeeds or not. This is PITA!
I don't even get it what's happening when the printer "cleanes the nozzle"? The nozzle doesn't wipe the platform but touches it, what does that "clean"? Could someone explain, please. Can I just disable the cleaning routine (how)?
RE:
What is this "nozzle cleaning" procedure needed for in the first place? I'd say it's the most annoying feature with Prusa printers, and now you can never be sure if your printing work will succeed or not. With my C1 and PETG it can occur multiple times in a row, and has made my 3D printing everyting than a smooth experience. Imagine starting a 20-hour job and coming a day later just to see nothing has been printed. Or not being able to just start a job and go away but you need to wait 5-10 mins to see if the cleaning routine succeeds or not. This is PITA!
I don't even get it what's happening when the printer "cleanes the nozzle"? The nozzle doesn't wipe the platform but touches it, what does that "clean"? Could someone explain, please. Can I just disable the cleaning routine (how)?
it's needed for the loadcell-based probing. Any foreign material on the tip throws off the readings.
To improve, make sure filament doesn't ooze (humidity, brand). A small half-drop forming on the tip will cause it to fail repeatedly.
You can AFAIK edit temperature settings in G Code, set a bit lower.
RE: Nozzle cleaning consistently fails with PETG
Does the cleaning routine then remove the foreign material from the tooltip? I doubt. Wiping would be much more efficient, I guess.
With me, the routine fails in a row, no matter if I brush the tooltip with the Prusa brush.
RE: Nozzle cleaning consistently fails with PETG
Older Prusa printers use inductive sensor to measure distance to printing plate, which is contactless but not very precise. You had to manually tune Z value for each printing plate. Loadcell replaced that and should give perfect first layer automatically, but the sensor is sensitive and probing requires touching the plate. Because of this, any filament residue in the printing head is now a problem.
Wiping indeed is how it should have been solved, and you can add that feature yourself. Current tapping approach I think only checks for consistency in the readings.
If it fails even though the print head is clean, you might have the same problem I had: strong currents in print head and print plate heating cables causes EMI to the low voltage unshielded loadcell sensor cable.
The fix was simple to do: open the back center panel and separate cables to two sets: high current power cables and the rest. Just use zip ties and try to make them farther apart from each other. Prusa should know better than this and use proper shielded cables for the sensors.