Jamming in V6 (retract)

Discussion in 'E3D-v6 and Lite6' started by z4ibas, Feb 28, 2016.

  1. z4ibas

    z4ibas Member

    Joined:
    Feb 28, 2016
    Messages:
    4
    Likes Received:
    0
    Hello,

    I have jamming problems in my V6 for more than 2 weeks. I can not resolve this anyhow.

    Extruder: Airtrippers v3 bowden
    Bowden tube ~30cm long
    E3D V6 Hotend, 0.4mm nozzle.
    Software: Simplify 3D
    Filmament: ColorFabb PLA/PHA 205 degress temp.

    While starting the prints, first layers are always OK, but whenever it wants to retract, after 1-2mins of printing with retracts, it fails. Hotend jams somewhere in heatbreak, extruder starts grinding filament or plastic starts bending in extruder. However printing with 0.5mm retract seems everything is OK, but V6 hotend oozes a lot and makes item strings on outer walls. Once the hotend jams, plastic cannot be pulled out, but it can be push in and extruded. Heatsink fan is connected directly to 24V PSU, so it's running always. I have reassembled hotend many times, cleaned everything, reaplied termal paste everywhere, but the problem persists. Adding a screenshot of simplify 3d anti oozing settings, please help me :)
     

    Attached Files:

  2. UlrichKliegis

    UlrichKliegis Well-Known Member

    Joined:
    Sep 5, 2015
    Messages:
    187
    Likes Received:
    47
    New filament make / charge? Does the part cooling fan switch on before this happens? Tried a somewhat higher hotend temperature? PID-parameters of the hotend tuned?

    Cheers,
    U.
     
  3. z4ibas

    z4ibas Member

    Joined:
    Feb 28, 2016
    Messages:
    4
    Likes Received:
    0
    I have disabled print cooling fans for first 3 layers. But printing first layers does not need retracts, so can't blame coolers. PID's are tuned 3 times right after installing hot end. This filament says that highest temp is 210 degrees, however I kept monitoring temperatures when extruding fails. Temperature varies only +- 1 degree.

    P.S. right now printing with 0.5mm retract and it does not fail. Dunno what else to do :S Stringing or jamming.
     
  4. UlrichKliegis

    UlrichKliegis Well-Known Member

    Joined:
    Sep 5, 2015
    Messages:
    187
    Likes Received:
    47
    Two thoughts: After having similar problems some time ago, I increased the hotend temperature - and I turned the heatbreak cooling fan upside down so that the lowest layer of the heat sink got some more of the air stream. If you look at it closely, you will see that the opening of the fan outlet hardly spends any air on the most important one, the lowest sheet. Don't ask why it worked so far... 3D printing is and stays an art and a mystery.
    But first, I'd just give it a try to increase the hotend temp. Just my two €uroCents.
     
  5. z4ibas

    z4ibas Member

    Joined:
    Feb 28, 2016
    Messages:
    4
    Likes Received:
    0
    I have tried printing at 215degrees temp, the problem still persists. Cooling fan is so low, that it atmost touches heat block.
     
  6. z4ibas

    z4ibas Member

    Joined:
    Feb 28, 2016
    Messages:
    4
    Likes Received:
    0
    OK some new reports. Changed extruder to I3D bowden. Added MK8 drive gear. Much more torque. Increase printing temp to 220 degrees. Minimised ammount of retracts. Problem still persists. When retraction is 2mm it always fails. 1,5mm fails too, plastic jams in heatbreak. Now it fails with any retraction. Heatsink is totally cool. What the heck?
     

Share This Page