Hot Extruder Motor / Proto Pasta Glitter Flake Jamming
Hey Everyone!
I just received my MK2S to MK3 upgrade kit and now have it fully assembled. I have been having some issues though. My extruder motor has been getting very hot during prints with PETG or Proto Pasta Candy Apple Red and Glitter Flake HTPLA. I would say hotter than the bottom of the build plate (not the top of the steel sheet) at 60C. Also, sometimes when I start a print (or in the middle of one) the extruder jams and I have to unload the filament, cut the tip off, and reload it. This has never happened on my MK2S even with these same filaments. I am trying to get the retraction dialed in, so I don't have fixed settings, but my temp is between 210 and 220C, Retraction 0.5 - 1.5 mm, Retraction speed 20 - 60mm/s, travel speed 250 - 350mm/s, Lift Z 0 - 0.5, and Retract before wipe 0% to 100%.
I'd appreciate any help I could get, and feel free to ask for more info if you need to.
Thanks!!
Mason Stewart
Re: Hot Extruder Motor / Proto Pasta Glitter Flake Jamming
It mainly jams when the hotend goes down to ambient and then heats up to start a print. Heat creep maybe?
Re: Hot Extruder Motor / Proto Pasta Glitter Flake Jamming
My extruder motor has been getting very hot during prints...
This *seems* normal for the MK3. A higher voltage and holding/running current results in a hotter running E stepper.
But...
The E stepper can get so hot (especially in an enclosure) that the bondtech gears will soften filament as its feeding it into the hot end. As you would expect, this causes all kinds of shenanigans.
I've read online (here for example) that typical stepper motors can operate upwards of 200 degrees F (100 C) before any issues. My extruder hovers around 110 - 130 degrees F (@50 C) so I'm really not concerned about it burning out or anything.
My big concern is the softening of the filament mentioned above. All that heat will travel down the shaft and eventually heat the bondtech gears on a long print.
I've added 40mm aluminum heatsinks to the extruder stepper in an attempt to mitigate this.
It drops the outer temp of the stepper by about 10 degrees F passively. I plan on adding fans to them to see how much more it can be reduced.
Not sure if any of the above even applies or could be helpful to your situation though. My apology if it comes off a bit ranty. Regards.
Re: Hot Extruder Motor / Proto Pasta Glitter Flake Jamming
Thanks, I will try that. Do you have any ideas about why it's jamming? Could they be related?
Re: Hot Extruder Motor / Proto Pasta Glitter Flake Jamming
Hello,
My printer arrives today, so I can't say that I've experienced this on a Prusa, but my first printer was a PrinterBot Maker. All of the motors on that ran hot, out of the box. I found out I could lower the drive current via controls on the circuit board, and the heat went away. No sense running more current through the motors than they need. Of course if the current goes too low, the printer has other issues.
Does the circuit board for the I3 have the drive currents adjustable?
Tay
Re: Hot Extruder Motor / Proto Pasta Glitter Flake Jamming
I don't think so.