Extruder Motor Getting Hot.



  • Hi I was wondering if someone would be able to help me with this issue.

    I am using Board: Duet WiFi 1.02 or later
    Firmware: RepRapFirmware for Duet 2 WiFi/Ethernet 2.05 (2019-12-13b1)
    Duet WiFi Server Version: 1.23

    I have just started to use my CoreXY Hypercube after it sitting there for a long time of not being touched after it was built with mainly the help of @Phaedrux which I am eternally grateful for.
    I was doing some test prints with it to makesure that everything was ok and found that the extruder motor is getting extremely hot, can't say excatly how hot but it is not comfortable to touch.

    The Test prints were being done with PLA and at about 70mms

    I am using a Trianglelabs BMG Clone extruder with a genuine E3D V6 hotend.

    The stepper motor is:
    Pancake UsongShine NEMA 17 1A (17HS4023)
    Model: 17HS4023 (XH-Linie)
    Holding Torque:≥ 130mN.m
    Motor weight: 132 g/piece.
    Size (L * W * H): approx. 42x42x23.5mm / 1.65 "x1.65" x 0.92 ".
    Rated Current (Single Phase): DC 1.0A. Rated Voltage: DC 4.1 V.
    Phase resistance(20°):4.1 X (1±10%)Ω/phase.
    Phase Inductance(1KHz): 4.1 X (1±20%)mH/phase.
    Positioning torque: 20 mN.m REF.
    Maximum no load Starting frequency:≥ 1400PPS.

    I originally had the power set to 800 in the config file and dropped it down to 600 in the hope it might help but it just seemed to make the extruder skip a lot so I tried to change the power to 1000 in the hope that it might allow it to run a bit easier if it was doing lots of retractions and not struggling with running on what I thought might be to little power and causing it to heat up.

    It doesn't seem to matter what power I set the extruder seems to get hot after about 15 minutes of use.

    All the other stepper motors I have controlling the axis's seem to stay cool which are a different brand.

    STEPPER MOTORS X, Y & Z AXIS:
    Stepperonline NEMA 17 1.5A (P/N 17HS15-1504S-X1)
    Motor Type Bipolar Stepper
    Step Angle 1.8 deg
    Holding Torque 45Ncm (63.74 oz .in)
    Rated Current/phase: 1.50A
    Phase Resistance 2.3ohms
    Inductance 4.4mH +/- 20%(1KHz)

    PSU:
    24v 500w 20.8A

    I did leave it to do a test print which took about 1 hour and 40 mins with 15% infill printing at 70mms which I noticed wasn't very good on the infill but the outer shell seemed to be ok.

    If anyone could give me an idea as what to do to solve this with the information I have provided I would be very greatful.

    Hypercube config.g



  • the rule of thumb is no more than about 85% of the rated motor current, so that would be 850ma for you.
    Too high and it will over heat and skip, too low and it will skip.
    How hot is hot? Can you still hold it?
    60 degrees is pretty normal



  • @jay_s_uk

    I originally had it set to 800 because of the rule of thumb with currents on stepper motors and it was hot and skipping. The skipping seemed to go away when I upped it to 1000 but it was still getting hot even though I allowed it to cool off before using it again.

    I can hold it but then I can hold a fresh cup of coffee so I don't think that will help much but I would say it is probably about 60c - 70c

    I have never had a extruder motor get hot before so I am not sure if this is what is causing the printing issue with the not so good printing results on the longer prints.

    I did run a 4 cube retraction test which was good but it only took about 20 mins to run.



  • are you sure your thermistor settings are correct and you're extruding at the right temperature?



  • @jay_s_uk yes they are set correctly as Phaedrux helped me originally set it all up and I haven't changed a thing since it was built and I have also tried printing the PLA at 190 to 215c

    When I print the PLA at 190c it doesn't make any difference with the extruder motor temp.

    Forgot to mention that I am running the Trianglelabs BMG clone as a bowden and not direct drive. I have also tried using 2 different bowden tubes. 1 no name and I am currently running the Capricom or how ever you spell it version as I thought that maybe the bowden tube was causing issues. I have also put a brand new e3D 0.4 brass nozzle on too and I can feed filament through the throat with the nozzle removed with no issues.



  • can you measure the resistance of one phase.

    Model no.: 17HS4023
    Size:424223mm
    Phase: 2 Phase
    Voltage: 12V
    Current: 0.7 A/Phase

    from what i can see the motor is 0.7A so 500ma would be better



  • @Veti said in Extruder Motor Getting Hot.:

    can you measure the resistance of one phase.

    Model no.: 17HS4023
    Size:424223mm
    Phase: 2 Phase
    Voltage: 12V
    Current: 0.7 A/Phase

    from what i can see the motor is 0.7A so 500ma would be better

    Well this has thrown a spanner in the works. it looks like there is 2 motors from the same company with the same model number.

    1 is 0.7A and the other is 1.0A which is what I am certain I have but I just removed the motor from the BMG to see the label and the writting is rubbed out but looking at the pictures the labels are slightly different and mine looks like from what I can see is the same as the 1.0A

    1.0A
    https://images-na.ssl-images-amazon.com/images/I/61oCibxPEQL.SL1500.jpg

    0.7A
    https://images-na.ssl-images-amazon.com/images/I/614OmoeLMLL.SL1120.jpg





  • @Veti this is definately the version I have which it says is the 1A version from this listing.
    https://www.amazon.co.uk/Usongshine-Titanium-Extruder-Printing-17HS4023/dp/B07L8CGQMB

    I have one of the other motors that I use to drive the X,Y & Z Axis's would I be better off putting that in ?



  • try the motor with 500ma first



  • @Veti said in Extruder Motor Getting Hot.:

    try the motor with 500ma first

    Ok will do thanks for the help Veti



  • @Veti I dropped the current to 500 and it seems to have worked. before starting to print extruder motor temp was 21.5c and 36.7 by the end of the print which was a 1 hour 40 min print. I didn't change any of the other settings so that everything was the same as before.

    The print quality is not great though. the infill is still very poor and so is the surface finish.

    Would you think it would be a good idea to do extruder and temperature calibrations again now that I have changed the current settings ?

    This is what the print came out like it is 60mm in height and was printed using .2 resolution.
    20210112_161107.jpg
    2.jpg
    3.jpg

    If I did the same print on my other printer the quality would be a lot higher.



  • check all bearing and pulleys. everthing has to be very smooth without resistance.



  • @Veti everything seems to move ok and I don't have the belts to tight I made sure of that.
    Is there a recommended way to check or is it more a case of feel ?



  • start with something simple like a calibration cube.
    then go to a retraction test print.


  • Moderator

    @RAM said in Extruder Motor Getting Hot.:

    Would you think it would be a good idea to do extruder and temperature calibrations again now that I have changed the current settings ?

    Yes. I would say that looks over extruded and maybe printed too hot.



  • Hi @Phaedrux will do that once the test print has finished. I changed the S3D Printing profile and did the 40mm cube which came out quite nice so decided to do something a little more crazy which is going well so far but I'm not holding my breath.

    Bet you hoped you would never have to deal with this printer again after all the issues I had at the very beginning lol.



  • Honest thoughts on this please with if there is anything that I could possibly do to improve the print quality.

    it was printed with Black Real Filament PLA @ 210c & 60mms with 0.4 mm nozzel at 0.2 resolution. no supports, cooling fan set to maximum after 4th layer. Retraction distance 3.50, Retraction speed 150mms

    Side
    20210113_133543.jpg

    Underside
    20210113_133611.jpg

    Top
    20210113_133635.jpg



  • the quality of the underside is determined by the quality of the part cooling.

    this print needs a lot of cooling and it has to be focused cooling.

    put some water in a shallow container underneath and see where the airflow is directed when the part cooling fan is on.


  • Moderator

    It also looks very glossy which can mean it's printed too hot.

    Look into doing a temp tower test where the temp gets changed at certain points up a tower so you can visually see the results. If the thermistor isn't very accurate when you think you are using 210 it could actually be 240. So in absence of accurate measurements, you can still determine a good set point experimentally. In other words, it doesn't matter if you use 190 or 220 so long as the results look good.



  • @Veti said in Extruder Motor Getting Hot.:

    the quality of the underside is determined by the quality of the part cooling.

    this print needs a lot of cooling and it has to be focused cooling.

    put some water in a shallow container underneath and see where the airflow is directed when the part cooling fan is on.

    20210114_170353.jpg

    It looks like the fan is blowing where it should be from what i can see



  • @Phaedrux said in Extruder Motor Getting Hot.:

    It also looks very glossy which can mean it's printed too hot.

    Look into doing a temp tower test where the temp gets changed at certain points up a tower so you can visually see the results. If the thermistor isn't very accurate when you think you are using 210 it could actually be 240. So in absence of accurate measurements, you can still determine a good set point experimentally. In other words, it doesn't matter if you use 190 or 220 so long as the results look good.

    20210114_171232.jpg

    Not sure what you think but 205c looks ok to me and it is also what is recommended on the filament.


  • Moderator



  • the water looks like you have two places where the part fans are blowing and its not underneath the nozzle.
    also it does not seem that strong


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