1. Got a question or need help troubleshooting? Post to the troubleshooting forum or Search the forums!

Solved Jamming of Pla

Discussion in 'Troubleshooting' started by BJS227, May 18, 2019.

  1. BJS227

    BJS227 Member

    Joined:
    Sep 19, 2017
    Messages:
    42
    Likes Received:
    7
    After printing great for awhile now. We have gone through 4 hot ends last week. After changing each we do a z offset, bed calibration and then a fine tune. After getting everything ready to go. The printer primes itself, and start in on the raft. After 2-3 layers which looks good the PLA jams in the extruder and the feed gear start to skip. There is plenty of z offset and by no means is it to close to the print. Also cleaned the spline gear and everything seem to not be binding. Any ideas how i can fix this?
     
  2. mark tomlinson

    mark tomlinson ༼ つ ◕_ ◕ ༽つ
    Staff Member

    Joined:
    Feb 21, 2013
    Messages:
    23,912
    Likes Received:
    7,338
    Is this on an R1? It doesn't sound like it :)

    Maybe you posted in the wrong section...
     
  3. BrooklynBay

    BrooklynBay Active Member

    Joined:
    Apr 7, 2018
    Messages:
    452
    Likes Received:
    50
    What is the temperature set to on the hotend?
     
  4. BJS227

    BJS227 Member

    Joined:
    Sep 19, 2017
    Messages:
    42
    Likes Received:
    7
    190 degrees with standard robo black pla
     
  5. BrooklynBay

    BrooklynBay Active Member

    Joined:
    Apr 7, 2018
    Messages:
    452
    Likes Received:
    50
    I've always had issues like this when the hotend wasn't set high enough. Raise the temperature then see if it still jams.
     
  6. mark tomlinson

    mark tomlinson ༼ つ ◕_ ◕ ༽つ
    Staff Member

    Joined:
    Feb 21, 2013
    Messages:
    23,912
    Likes Received:
    7,338
  7. BJS227

    BJS227 Member

    Joined:
    Sep 19, 2017
    Messages:
    42
    Likes Received:
    7
    What temp would recommend
     
  8. BJS227

    BJS227 Member

    Joined:
    Sep 19, 2017
    Messages:
    42
    Likes Received:
    7
  9. WheresWaldo

    WheresWaldo Volunteer ( ͠° ͟ʖ ͡°)
    Staff Member

    Joined:
    Feb 18, 2015
    Messages:
    5,905
    Likes Received:
    3,593
    Usually you can take the recommendation and increase it by 10% with no issues, so if the filament maker says 190°C then you can usually go all the way to 210°C without issues.
     
    mark tomlinson likes this.
  10. mark tomlinson

    mark tomlinson ༼ つ ◕_ ◕ ༽つ
    Staff Member

    Joined:
    Feb 21, 2013
    Messages:
    23,912
    Likes Received:
    7,338
    I always test around the range they spec for the filament. Start at the top of the range and print something small (like this: https://www.thingiverse.com/thing:66175) and then lower it 5 degrees and try again. When it is right you have your temp. For that spool, on that printer, in that room at that environment/room temp ;)
     
  11. WheresWaldo

    WheresWaldo Volunteer ( ͠° ͟ʖ ͡°)
    Staff Member

    Joined:
    Feb 18, 2015
    Messages:
    5,905
    Likes Received:
    3,593
    One note about PLA, it gets stickier the hotter you extrude it. Simply chemistry. But it does flow easier.
     
  12. BrooklynBay

    BrooklynBay Active Member

    Joined:
    Apr 7, 2018
    Messages:
    452
    Likes Received:
    50
    Some brands such as Inland specify a different temperature range for regular pla & pla +. On my machine, my temperature for this brand is set a little higher (235° C). I'm sure that you could print it at 10° or 15° lower but on my machine the print quality, speed, and layer adhesion start to display issues. You could try a print tower test with different brands then save the results into specific print profiles for future use.
     
  13. BJS227

    BJS227 Member

    Joined:
    Sep 19, 2017
    Messages:
    42
    Likes Received:
    7
    Do you check temp with heat gun or on screen readout. On mine they seem very different.
     
  14. mark tomlinson

    mark tomlinson ༼ つ ◕_ ◕ ༽つ
    Staff Member

    Joined:
    Feb 21, 2013
    Messages:
    23,912
    Likes Received:
    7,338
    Not sure how you would accurately read the internal temperature of the heater block any more accurately than than an attached thermistor :)
     
  15. BrooklynBay

    BrooklynBay Active Member

    Joined:
    Apr 7, 2018
    Messages:
    452
    Likes Received:
    50
    The thermistor is next to the heating element so it should be accurate. What does the thermal IR gun show compared to the thermistor reading? Some multimeters have a heat probe (thermistor) for direct measurements.
     
  16. mark tomlinson

    mark tomlinson ༼ つ ◕_ ◕ ༽つ
    Staff Member

    Joined:
    Feb 21, 2013
    Messages:
    23,912
    Likes Received:
    7,338
    An IR gun is tricky on the heater block and I know -- I have tried,
    Even when you get it reading it is reading the external temperature, not the internal.

    Very hard to get an accurate read.
     
  17. WheresWaldo

    WheresWaldo Volunteer ( ͠° ͟ʖ ͡°)
    Staff Member

    Joined:
    Feb 18, 2015
    Messages:
    5,905
    Likes Received:
    3,593
    Also don't expect accuracy to the nearest degree, we are working with commodity Chinese electronics and a lookup table that is only a theoretical representation of the thermistor type. It's all about compromises.

    When we are dealing with things like these you have precision, accuracy and repeatability, pick any two. In our case you don't get to pick, we have only precision and repeatability, so it can precisely measure differences in temperatures, and it can repeat those measurements, but since we are translating electrical signals against a general table we are lucky if it is accurate. But 3D printing and melting extrude is very forgiving and we don't really need accuracy to melt and print with plastic.
     

Share This Page