Jump to content

niamor2

Dormant
  • Posts

    10
  • Joined

  • Last visited

Posts posted by niamor2

  1. 17 hours ago, gr5 said:

    PVA and Nylon need to be kept quite dry.  Especially nylon.  I don't leave my PVA on the printer overnight if it's not printing.  I keep it in a sealed bag.  Whenever I get new filament with new dessicant I move the dessicant packet to my nylon and pva bags as the PLA really doesn't need it.

     

    You can tell if PVA is too wet (or any material) because it sizzles and pops while printing and comes out more snowy than clear (lots of micro steam bubbles).  You can "repair" the PVA by heating it but it gets soft at 65C so I wouldn't heat it beyond 60C.  You can put it on a heated bed at 60C with a towel over it for 10 or 20 hours.  I suspect that will work.  Assuming that's the problem.  PVA is annoying in that if it gets too dry it also fails (gets brittle).  60C should be safe.  You want I think around 10-20% humidity.

     

    Using this slider: http://www.dpcalc.org/

    Let's assume in your building the temp is 20C and humidity is 60% then the dew point is 12C.  Crank temp up to 60C using the calculator above and slide the humidity down until you get 12C dewpoint still and your new humidity is about 7% (heating air won't change the dewpoint but it lowers the humidity).  I'm not sure this math is the correct way to calculate things for drying filament but it's what I use.  That should be safe I would hope.  It just might take many hours for the water to escape the pva - especially on the inner turns of filament deep in the spool.  Anyway I've used this trick (heat it to 110C for nylon) to dry nylon to great success.

     

    Thanks a lot ! For now I will try putting the spool in an airtight pouch with dessicant for several days. If that doesn't work I will try the heated bed.

  2. 1 hour ago, Ghene said:

    Get a nylon paint brush and vacuum cleaner. Remove the bowden tube.
    Then try to dislodge the ground filament while sucking them out.


    If that fails, try this... 
    https://ultimaker.com/en/resources/50688-clean-the-feeder

     

    Thanks for the advice, but I already removed the bowden tube, and I couldn't remove the filament no matter what. So I tried your last solution, and here is what I found :

     

    IMG_20180621_101909.thumb.jpg.386a56d7e77298608978129fc5adbd85.jpgIMG_20180621_101924.thumb.jpg.2d77bc0dbc06a9c1f5863dba0e7294d0.jpgIMG_20180621_102213.thumb.jpg.fc7ca6af2bd9ad18fff70834ed36c741.jpgIMG_20180621_102222.thumb.jpg.d5aa0de06b7aa6e2349e5e478619ce5f.jpgIMG_20180621_102825.thumb.jpg.57038e002503bb7a0888c22c36abedcf.jpg

     

    I don't understand how that could happen, but it seems the filament folded inside the feeder... explaining why I couldn't remove the filament manually !

     

    So I finally extracted the filament successfully, and launched a print with a new PVA spool : everything seems to work properly !

     

    Conclusion : NEVER try to print with a PVA spool that remained a long time in the open air !

     

    • Like 1
  3. Merci pour vos conseils !

     

    J'ai donc démonté le feeder, et voici ce que j'ai trouvé :

     

    IMG_20180621_101909.thumb.jpg.52a1cd9d4cd8f383806e73b1fc88630f.jpgIMG_20180621_101924.thumb.jpg.2e3125857eeadea0d4f5d481c1ba1ffd.jpgIMG_20180621_102213.thumb.jpg.5f25a9b5900e4f804994e92f461eab1f.jpgIMG_20180621_102222.thumb.jpg.2e9701fb6e90c6b1325bab37895c27f3.jpgIMG_20180621_102825.thumb.jpg.a1bee5814c5c00c1b10db58f0841da46.jpg

     

    Je ne comprends pas comment ça a pu arriver, mais il semble que le filament se soit replié à l'intérieur du feeder... Il y avait donc 3 épaisseurs de filament passant par le feeder, pas étonnant que je n'arrive pas à l'extraire manuellement !

     

    J'ai donc finalement réussi à extraire le filament, j'ai remonté le feeder et j'ai lancé une impression avec une bobine neuve de PVA, et tout est apparemment rentré dans l'ordre ? Je vais tenter de récupérer l'autre bobine en la laissant dans un sachet fermé avec du dessicant.

     

    Conclusion : ne JAMAIS lancer d'impression avec du PVA laissé à l'air libre pendant un mois !

  4. Hi everyone,

     

    I'e got a serious problem with my last print with PVA on my Ultimaker 3 : the material stopped extruding after 1hr, and while trying to unload the PVA filament I realized it was stuck in the feeder. Then I removed the bowden tube at both ends, removed the PVA filament from the printhead, and cut the filament under the feeder. But I still couldn't remove the filament, whatever side I pulled on :

     

    IMG_20180620_150413.thumb.jpg.e91feda11d975f6ddab49724158a7fd3.jpgIMG_20180620_150423.thumb.jpg.202422a90b7f8905f37195bdd1af1df1.jpg

     

     

    I guess that might be caused by a degradation of the filament by ambient humidity : the spool was left out in the open air for more than one month. But I still don't know how to remove the filament from the feeder. May be I could try moistening the filament in the feeder to soften it and remove it more easily ? Or will I have to disassemble the feeder completely ? Any ideas ?

     

     

    Thanks !

  5. Bonjour à tous,

     

    J'ai un gros problème concernant ma dernière impression avec du PVA sur l'ultimaker 3 : l'impression a cessé d'extruder après plus d'1 heure d'impression, et en voulant retirer le filament de PVA je me suis rendu compte qu'il était coincé dans le feeder. J'ai ensuite retiré le bowden tube des deux côtés, puis retiré le filament de la tête d'impression, et coupé le filament en dessous du feeder, mais malgré cela et en tirant dans les deux sens, impossible de faire bouger le filament :

     

    IMG_20180620_150413.thumb.jpg.7c3c72d4482dc473c6a2c79baf751e2a.jpgIMG_20180620_150423.thumb.jpg.b3785fa939bd7195d3f67520590e18c2.jpg

     

    Je suspecte que ce phénomène pourrait être dû au fait que la bobine est restée à l'air libre pendant plus d'un mois, le matériau a pu être dégradé par l'humidité ambiante.

    Toujours est-il que je ne sais pas comment me sortir de là. Peut-être que je peux essayer d'humecter le filament dans le feeder pour le ramollir et l'extraire plus facilement ? Ou faut-il que je démonte entièrement le feeder ? Vous avez des idées ?

     

    Merci d'avance !

×
×
  • Create New...