PLA oozeing instead of Extruding

Hello all, I got in six pounds of IC3D PLA yesterday so I can print a helmet for a friend. Any how I am having some serious issues. Before I used PLA I printed around 15lbs worth of IC3D ABS using the same extruder setup and every thing. I have an Itty Bitty Double Extruder, works great with my ABS but the PLA is causing issues. At first it seemed to work well it would extrude at 190 fine but I had chunks of ABS getting caught so to clean it out I had to run it at 220. Came out fine. just very clear and gooey. Eventually I was just getting PLA so I decided to turn off my hot end and go to bed. I came around today to try and print and some how the PLA clogged up my extruder by expanding and sticking to some of the ABS on the guiders. I took it apart cleared the jam and now I start to print. How ever now the PLA just kinda oozes out slowly. I ran a small drill bit used for cleaning nozzles to try and clear any gunk out but that did nothing. I tried turning the temperature all the way up to 230 and I still have the same issue where it oozes out instead of extruding properly. Does any one have and idea as so why it is doing this? I haven't even managed to print the first layer of a small cube because of this.

Edited 1 time(s). Last edit at 07/10/2015 12:31AM by cayoke.

Have you checked to make sure the extruder didnt strip the filament? I assume you checked this, but it doesn't seem clogged to me if it is oozing? maybe the PTFE tubing is clogged? Heating PLA too hot will cause it to expand further up the hot end inside the PTFE tubing and it jams.

---

My creations/2020 aluminum parts/FolgerTech i3 upgrades [www.thingiverse.com]

Thank you for your reply!

The extruder did strip the filament but not nearly to the point that it would stop extruding. I'm going to need some clarification. What exactly is the PTFE tubing? I had an issue where it expanded and jammed in the 3D printed part of the extruder but I managed to clean that out. I have not check to see if it has clogged in the actual metal 'heat sync' which is called the Hexagon hotend upper half. But when I retract the filament it comes out with the tip melted.

I have a Maker Farm Prusa I3v 12"

My guess is, you have glass-hard ABS splinters inside the nozzle, that partially hinder the extrusion.
Using a nozzle for different material seems a bad idea, because I've read the same problem before in this forum.

-Olaf