I had to clean my Reprap's nozzle with a blow torch.
I haven't been posting here because my Reprap has been very finicky lately. I almost didn't bring it to Maker Faire (Detroit 2011) because it was so unstable. It wouldn't print PLA at all, ABS was fine though. I made a quick video once I cleaned out the nozzle throroughly. I've cleaned it before following ReprapLogPhase's video here https://www.youtube.com/watch?v=6bTfl35zlHE But, I didn't clean it enough this time (this is the second time this nozzle has gotten clogged). Lesson learned: if you're going to use a blowtorch on your nozzle, keep doing it until all the smoke is gone. It takes some experience to know when your nozzle is really cleaned out.
I guess I should ask, does anybody know of a safe way to switch between ABS and PLA? It seems everytime I switch I need to clean my nozzle out.
Fixed my Reprap nozzle (blocked by ABS) from Mark Kimsal on Vimeo.
Sorry, this video is kinda loud.
I said "Maker Gear", but I meant "Maker Faire" (Detroit 2011)
If your extruder nozzle isn't easy to push by hand it needs to be cleaned. I could push plastic out of my nozzle, but I needed to grip the filament with pliers. If you need to force your plastic out with pliers, there's junk in your nozzle.
I cleaned out the nozzle once before, but the second time ABS gunked it up, I didn't clean it out enough. Keep burning it until black smoke comes out if you have been printing ABS and switched to PLA (only if your PLA won't extrude easily). Then keep heating it up until no more smoke comes out. Burn it out according to ReprapLogPhase's video, but do it with lots of ventilation and a fan on your alcohol (explosive fumes build up).