Okay, I cleared the barrel and reattached the nozzle and barrel at print temperatures, as you recommended. The PTFE tube inside the barrel came out, but I was able to reinsert it. A 100mm test extrusion showed no immediate problems. I also adjusted my Slic3r settings to keep the fan on, to ensure a stronger temperature gradient. I have also attached pictures of the extruder, hotend, and printby Sargent890 - Reprappers
I purchased my first 3D printer, a RepRap Mendel Prusa i3 about 3-4 months ago. I had been printing with ABS with a fair amount of success for a while. I switched to PLA about a month ago. When I first did this, my print quality skyrocketed, I was getting comparatively amazing results out of my printer. However, about a week and a half after the filament switch (after some particularly heavyby Sargent890 - Reprappers