UPDATED 3-6-16: The Connection part has been modified to have wider rails that fit into the groove on the arm part. I have had issues with the arm falling out of the groove, so widening the rails by .4mm on each side should do the trick.

A remix of http://www.thingiverse.com/thing:231725 to work with a Kossel 2020 delta printer.

Holder has a quick removal connection and contains 2 12x28x8mm bearings that you can get on ebay or Amazon for a couple bucks each, for super smooth low-friction movement. I got 2 bearings delivered for $3.30 here: http://www.ebay.com/itm/231075663249

I remade the attachment for fit my Kossel delta printer with 2020 extrusions. The spool holder does not extend straight out from the tower, but is offset to alow the filament to feed off the spool more inline with the extruder motor.

It has worked flawlessly since I installed it. The only tip I can give is this: the weight of the spool tends to cause the holder to flex a bit at the attachment. Installing a tiny washer or 2 bewteen the bottom of the mounting bracket and the tower to push out the bracket and thus angling the bracket up a couple degrees will result in a perfectly level holder once the spool is placed on it. This prevents the spool from walking to the outside of the holder.