timelapse & instructions : http://youtu.be/CvMu79ZCd9AThis design is influenced a lot by the designs of |robert| & "Geeks". Thanks for your great work !!!https://www.youmagine.com/designs/alternative-um2-feeder-version-twohttps://www.youmagine.com/designs/extruder-um2-version-2And a big thanks to Ultimaker for the published STEP files I could use to take the measurements from!!update: 30/6/14 > added a little knob for easy spring adjustment (see last picture)update; 2/7, as cor3ys already mentioned in the forum the arms holding the bearing are a bit to short (sorry, I only tested at low speeds...) updated the file. Version nr. 25 of the front and back arm have 2mm increased length.At the same time made a little change for easier installing the m3 x 50mm bolt...