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Extruder skipping and DAC_MOTOR_CURRENT_DEFAULT in Firmware

Discussion in 'General Questions' started by Jordan H., Feb 19, 2020.

  1. Jordan H.

    Jordan H. New Member

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    Has anyone played around with this value in the firmware for the R2? Before I kill a board or driver testing, I wanted to check and see if anyone had tweaked these settings with any luck. The max extrusion speed seems to be quite low before I start losing steps on the extruder (I use a lot of PETG @ 242C w/ .3mm layer height for part testing). Increasing the temp only nets me a small increase in feed rates. I understand that this printer doesn't utilize any gearing on the extruder for higher torque but it still seems to underperform with extrusion speeds in comparison to older Robo offerings. Any input would be helpful. Thank you!
     
  2. mark tomlinson

    mark tomlinson ༼ つ ◕_ ◕ ༽つ
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    AFAIK there is no software control of motor current in the Robo machines.
    Our delta supports this, but it uses completely different electronics (Rambo board) and while it looks different the Robo board is still effectively an Arduino Mega and a RAMPS.
     
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  3. Jordan H.

    Jordan H. New Member

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    Thank you! That's what I was afraid of, but I was hoping I was wrong since Robo customized the line and put their [robo] comment on it.
     
  4. tkoco

    tkoco - -.- --- -.-. ---
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    The motor might be overheating. Check the shaft of the extruder motor after printing for a while. If it is very hot, please consider this mod: http://community.robo3d.com/index.php?threads/r2-extruder-mod.23518/
     
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  5. Jordan H.

    Jordan H. New Member

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    Thank you. I will check that for sure. It happens right after bringing the hotend up to temp too, but it is good to know there have been issues with that and that there is a solution.
     
  6. Jordan H.

    Jordan H. New Member

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    So I just wanted to give an update, it seems that my issue was due to that fact that the stock extruder was just not powerful enough to do what I wanted to do. I replaced the stock extruder setup with an e3d Titan using the adaptor from WheresWaldo (I will link it as soon as I have enough posts). The 3:1 gear ratio seems to have fixed my issues, I can print at 80mm/s with no issue now if I like.

    tkoco, I will have to add the mod you linked for sure now, the Z stepper runs much hotter after this mod (not dangerous but I would like to prevent premature failures), thank you for linking the heatsink mod. mark tomlinson, thank you for your quick and knowledgeable responses in this and many other topics. I have been a member and a robo owner for a long time and haven't posted, but you and WheresWaldo have inspired me with your contributions, as well as many other members. It's far past due that I give back to the community!
     
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  7. mark tomlinson

    mark tomlinson ༼ つ ◕_ ◕ ༽つ
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    Different styles of printers need cooling for the steppers. Our Cartesian style printers are fine even when worked long and hard, but our large delta requires heat sinks on the x/y/z axis to stay reasonably cool when operating (it has a 3ft tall volume and that means a lot of stepper movement). Direct driven extruder drives (like the C2, R2 and even our big delta) use a much higher duty cycle for the motor and it will work harder to get the job done than a geared one. At one point I stuck a GregsWade on our delta to try and help it out -- it worked, but we later just removed it and used the heat sinks :)
     
  8. tkoco

    tkoco - -.- --- -.-. ---
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    The mod keeps the extruder motor very cool even with the demands of printing with NinjaFlax filament.
     

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