I have a twin screw extrusion with a die that has a nozzle diameter of 2.0mm. Therefore, the extruded filament are 2.0mm thick. However, I tried to feed it into the print head but it does not fit it. I am wondering has anyone had any experience in using 3.0mm thick filaments? Can I change the print head to fit a thicker filament? I am using a Makerbot Replicator 2X. Thanks very much.