Whenever the nozzles on my PowerSpec Ultra 3D printer clogged, I can unclog them by loading filament into them. Last night was the first time that I was not able to unclog one of the nozzles by loading filament into it. Following the tutorial at http://www.instructables.com/id/Uncl...forge-Dreamer/ , I had to disassemble one of the extruders. How is it possible for PLA filament to get so clogged in the nozzle that I had to disassemble the extruder? Should I buy new nozzles shown at http://www.amazon.com/gp/product/B01...f_rd_i=desktop ?