I am using a Lulzbot TAZ 6 at work for some prototyping, and we have chosen to use PLA + PVA so that we can build support materials and easily pull off/dissolve our supports, but this has been coming with a litany of problems. For some reason both filaments are starting to have problems extruding. I have successfully printed sample models in each filament with none of these problems, but when I go to do dual printing with all the settings the same, I’m seeing serious problems.
For the PLA, I am seeing the drive gear tearing into and eating away the filament, thus not actually allowing it to extrude or retract. This can happen multiple times in a print, and consistently so. I have also seen this happen to our reel of ABS, but found out that it occurred because the filament got caught and couldn’t un-ravel at all. I know the nozzle is clean (cleaned it twice), temperature is adequate (215C), and I even turned of retraction. My fear is that the stress of actually feeding the filament is somehow causing the drive gear to instead tear apart the filament instead of driving it to the hot end to be extruded.
The PVA is another story. This stuff isn’t really fun to work with to begin with so it is pretty frustrating in general. Regardless of my views on it as a material, it seems to be struggling to extrude as well. Again, the extruder was clean, temperature is adequate (190C), and no retraction. The filament in this case though doesn’t get ground off until it pig-tails and jams between the drive gear and the hot end. This happened multiple times and mysteriously vanished. I think the only setting I changed was the print speed in Cura, but that doesn’t seem to have that much effect, so I’m wondering what exactly was causing this.
Does anyone have any tips/thoughts on what may be happening?
I’ve been thinking of printing an alternate spool holder like this one: http://www.thingiverse.com/thing:725128. If my suspicion about the stress of feeding the filament is correct, I think that this may be a possible solution.
I will try to attach pictures of what I’m seeing, but this forum setup keeps rejecting when I add attachments…
Any thoughts/help would be greatly appreciated.