Extruder Motor running Hot

mattbenimble

Hi,

My extruder motors (https://images-na.ssl-images-amazon.com/images/I/81rKW7OedjL.pdf) are running really warm (55d C) during an avg. print (2hrs). Here is the Config that im using currently:

; Drives
M569 P0 S1 ; Drive 0 goes backwards
M569 P1 S1 ; Drive 1 goes forwards
M569 P2 S0 ; Drive 2 goes backwards
M569 P3 S1 ; Drive 3 goes forwards
M569 P4 S1 ; Drive 4 goes forwards
M350 X16 Y16 Z16 E16:16 I1 ; Configure microstepping with interpolation
M92 X100 Y100 Z400 E399.54:409.35 ; Set steps per mm
M566 X900 Y900 Z12 E120:120 ; Set maximum instantaneous speed changes (mm/min)
M203 X6000 Y6000 Z180 E1200:1200 ; Set maximum speeds (mm/min)
M201 X500 Y500 Z250 E250:250 ; Set accelerations (mm/s^2)
M906 X1000 Y1000 Z1000 E400:400 I30 ; Set motor currents (mA) and motor idle factor in per cent
M84 S30 ; Set idle timeout

Do you have any idea of why they would be running so hot? Given that the stepper is rated at .4 Amps, should it be set to lower than 400mA in the config?

Thanks in advance!

elmoret

55C is normal for running a stepper at its rated current. If you don't need all the rated torque, back down the current.

deckingman

To elaborate on elmoret's comment, the spec for your motor has a temperature rise quoted as 80deg C so 55 is fine.

mattbenimble

ahh. i read that as the threshold of demagnetization. im glad to hear that it can run hot and not break. Thanks!!!

Dougal1957

Having said that you may be advised to look for a motor with a higher Current but much lower mH value

DjDemonD

My 20mm nema 17 gets quite hot probably in that range, it's not an issue but you don't want printed brackets softening so how about a mk8 extruder aluminium heatsink bonded to the back. Runs fairly cool now barely any mass added.

deckingman

@DjDemonD:

My 20mm nema 17 gets quite hot probably in that range, it's not an issue but you don't want printed brackets softening so how about a mk8 extruder aluminium heatsink bonded to the back. Runs fairly cool now barely any mass added.

Good idea DJ - quieter than a fan too.