Printrbot Metal Plus Spool Holder

Minimalistic spool holder for the metal plus. Add as many of the "middle" brackets as you like for support for longer rods and more spools. A printable 17cm long rod is included, alternatively you could probably use a 7.5 or 8mm metal rod. (I haven't tried that)

Requires 4 8mm diameter skateboard bearings, like these ones: http://www.amazon.co.uk/gp/product/B00EPNN62M

There are three different variants of rod ends which might give you different results depending on your printer: a normal one, a thicker one and a tapered one. The tapered one's inner diameter gets smaller towards the top for better grip on the rod.

One file includes everything you need except the rods which really should be printed separately one by one. The combined file contains all three variants of rod ends, so you'll have some bits left over.

It might be a good idea to add a dab of super glue on the bearing casings and/or rod ends for additional stability.

I'd recommend printing everything with 100% infill and 0.2mm layers (at most), for biggest stability.

Note: you might get intro trouble when printing small infill areas at high speed when using this if you hit a resonant frequency. Lots of vibration. Bad news.