I love Satoer's Bowden feeder http://www.thingiverse.com/thing:159159 I have tried and printed a lot of differerent extruders/feeders but I went with his as it seemed to jam the least, looks great, and it is just so easy and convenient to use, I take no credit for the Bowden feeder at all this is all his idea, I just tweaked it. I am running a dual head and wanted one on each side of the printer so I flipped the base and the top and then reversed the writing so that is still reads properly, the only other change was to make the outlet hole 8mm like the inlet hole so that I could tap it and thread on a fitting. All the other parts are the same and just need to be turned over once printed. Please see http://www.thingiverse.com/thing:159159 for detailed instructions