Very hot extruder stepper during MMU2 print only
Has anyone else noticed the stepper motor for the extruder getting very hot only while printing multiple colors?
With single color prints it just gets warm. With multi color, it is getting to where you cannot touch it for more then 2 seconds.
I am running the MK3s and MMU2s, just printing PLA at 205. It is really hot after 20 minutes or so. 3.7 Firmware.
I know the stepper current is bumped up during filament exchanges, but this seems excessive.
I am suspicious that the heat may be softening up the filament at the bondtech gears too much and causing jambs. I can't see to get more than 30-40 minutes into a print before a jamb.
I am using slicer PE and the only thing I changed was the cooling moves from 1to 4.
The pic is the filament that jammed last, after a cold pull.
Re: Very hot extruder stepper during MMU2 print only
My extruder motor is about 50 degrees Celsius (122F) when printer single color and about 60 degrees Celsius (140F) when printer multi colors and this is after several hours into printing
I think it's very important to try to get the filament to go with the least resistance through the tubes and buffer etc.
Re: Very hot extruder stepper during MMU2 print only
i am starting to think they screwed something up. even my mmu temps started going high. but at least I have a fan I used to run on the extruder. .. but wonder what they broke with the "S" firmware. something is wrong.
I have a Prusa,therefore I research.
RE: Very hot extruder stepper during MMU2 print only
I need to investigate that path. I made a lot of changes all at the same time, and filament path and spool holders was two of them.
I am having jambs at relatively the same point/time, so I think it is heat related and you may be on to something. I am going to go back to the messy short tubes I had before and try the exact same print and see if there is a difference.
Thanks for the thought kick. 🙂
RE: Very hot extruder stepper during MMU2 print only
Same issue here. The bondtech shaft and gears are running very hot with my MMU2S. This causes the PLA filament to melt, followed by a jam.
RE: Very hot extruder stepper during MMU2 print only
make sure your slicer is set for mmu2s.
after changing mine to the "s" it seems to be behaving better. I will turn my added fan off tonight and see if it still gets hot.
I have a Prusa,therefore I research.
RE: Very hot extruder stepper during MMU2 print only
Has anyone else noticed the stepper motor for the extruder getting very hot only while printing multiple colors?
With single color prints it just gets warm. With multi color, it is getting to where you cannot touch it for more then 2 seconds.
I have been having the same issue for a long time.
things that i have learned cause the higher temp.
1. ptfe tube not aligned with bondtech gear and or the ptfe is damaged
2. the idler bearings are dirty or not properly installed
3. the idler is not mated correctly to the bondtech gear
4. the idler spring screw is too tight.
5. the extruder motor is not at 6.5 ohms +-10% at room temperature