Cold pull recommendation
What is the recommended way doing a cold pull with the MMU2S?
Do I remove the chimney and the door screw or the door screw, the hinge screw and the Festo connector?
Re: Cold pull recommendation
Only thing I remove is the festo at the top of the extruder body. Heat to 210, insert filament into nozzle, cool to 100 and pull with pliers.
Peter
Please note: I do not have any affiliation with Prusa Research. Any advices given are offered in good faith. It is your responsibility to ensure that by following my advice you do not suffer or cause injury, damage…
Re: Cold pull recommendation
Only thing I remove is the festo at the top of the extruder body. Heat to 210, insert filament into nozzle, cool to 100 and pull with pliers.
Peter
Doesn't this generate too much reverse voltage when the extruder motor is still engaged?
Re: Cold pull recommendation
Only thing I remove is the festo at the top of the extruder body. Heat to 210, insert filament into nozzle, cool to 100 and pull with pliers.
Peter
Doesn't this generate too much reverse voltage when the extruder motor is still engaged?
no. Many years of folks doing this with no issues.
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Chuck H
3D Printer Review Blog
Re: Cold pull recommendation
What cold pull temps have folks found that work for different filament types?
90C works for PLA but I have yet to have much luck with PETG as it always either strings or breaks off; haven't found the sweet spot yet despite both
pulling as soon as it starts to free up or waiting a little longer.
I print with black PETG often so it'd be nice to get good cold pulls on that when switching back to a lighter colour....
Re: Cold pull recommendation
I use nylon and I heat to 260-270 fro 5 minutes then cool to 90 and pull.
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Chuck H
3D Printer Review Blog
Re: Cold pull recommendation
For what it's worth, I did not recognize this was for the MMU ... the following is stock MK3.
I use whatever is in the printer: I do open the idler door rather than chew up filament and create extra dust.
From cold: set nozzle heat to 90c for PLA (120c if PETG) then immediately start pulling on the filament with fingers. At some point the filament starts stretching so I never jerk or I'd break the filament, and with constant tension the filament finally comes loose of the colder spots in the nozzle.
Some people report lifting their printers off the table, I pull just hard enough that doesn't happen.
Re: Cold pull recommendation
I use whatever is in the printer: I do open the idler door rather than chew up filament and create extra dust.
From cold: set nozzle heat to 90c for PLA (120c if PETG) then immediately start pulling on the filament with fingers. At some point the filament starts stretching so I never jerk or I'd break the filament, and with constant tension the filament finally comes loose of the colder spots in the nozzle.
Some people report lifting their printers off the table, I pull just hard enough that doesn't happen.
Thank you, I'll try 120 for PETG next time and see how it does.
Re: Cold pull recommendation
An interesting aside regarding "glass transition" of FDM plastics ... I think ymmv is an adequate prelude to think of it that way: but the fun part was the mention of hysteretic material properties. That comment alone explains why I've seen some of the FM (a certain kind of magic, aka, inexplicable effects) when doing cold pulls.