PVA Glass in Extruder

This is for general discussions. Also FAQ can be found here.

Moderator: speedake95

Post Reply
WayneC
Posts: 17
Joined: Tue Sep 02, 2014 3:42 am

PVA Glass in Extruder

Post by WayneC »

I finally got comfortable using my single head with PLA, so I decided to add the second head and try printing with PVA as support material. I googled the printing temperature and I saw ranges from 160 to 200. I tried 190, and now it appears that the extruder is glassed up. I've seen lots of posts on cleaning PLA or ABS from extruders, but not much on PVA. Is drilling it out my only option?

Dreide
Posts: 176
Joined: Sun Sep 29, 2013 12:32 am
Location: Lausanne, Switzerland

Post by Dreide »

What do you mean by "glassed up"?
Apparently, PVA is more critical regarding the maximal temperature above as it decomposes faster than other material when too hot. Still, I would try to get the extruder free by raising the temp and possibly by helping the extruder motor by pushing the filament also manually.
As an alternative for drilling - PVA is water-soluble, so you could let the extruder soak in water over night (after having removed the thermistor and heater, or at least after having switched off the printer).
Felix 2.0->3.0dual * Repetier (host+firmware) * KISSlicer Pro, Simplify3D * Cubify Design

WayneC
Posts: 17
Joined: Tue Sep 02, 2014 3:42 am

Post by WayneC »

I have read that PVA will crystalize at high temps, and I've seen the term "glassed up" used someplace to refer to that condition. I remember reading that once the crystallization happens with PVA, it is very difficult to remove. I have tried re-heating and manually pulling out the filament, with no success. I've since disassembled the extruder and pulled off the thermistor and heater. I'll give it a soak. Thank you Dreide.

reeja
Posts: 1
Joined: Sat Dec 27, 2014 1:16 pm

Post by reeja »

Thanks for response WayneC......
reeja

emdash
Posts: 5
Joined: Sun Oct 26, 2014 5:59 pm

Post by emdash »

Any luck?

WayneC
Posts: 17
Joined: Tue Sep 02, 2014 3:42 am

Post by WayneC »

Soaking it did not help. I took the whole thing apart and reamed out each part with either a drill bit or piece of wire. In the end I got it all cleaned out.

Post Reply