This is a derivate of http://www.thingiverse.com/thing:3680, which should be consulted for instructions. The only addition of this thing is, that I already had filament on a spool, and did not want to create a wooden spool. Hence I designed a small spindle holder.

Print 2 spindle holders according to the diameter of your spindle. The sketchup file is included for modifications. Mine had a diameter of 52mm. I just put a screw through both to stabilize it a bit and the end of the screw goes through the bearing.

Make sure that your plastic spools has a rim somewhere, so that you can adjust the bearings to follow it.

I also could not find the proper tube, hence I just used a gardening supply water hose. Will see how it works. (Addition: it does not work at all :-( Just to much friction.