This allows the Replicator 2X to print PLA. By sliding the filament through a sponge dabbed with oil, the PLA filament doesn't stick to the extruder heater tube.
1: Cut a small strip from a dense sponge and put it in the larger piece.
2: Put on several drops of oil.
3: Slide the PLA filament through both pieces.
4: Push the small piece into the large piece and twist counter-clockwise to lock it in place.