Spool Skeleton Mount for Delta Kossel

I needed to print a new spool holder for a Kossel Mini, and the "Spool Strong Arm Mount for Delta & Kossel Printers" by bryhil looked interesting, but a bit overkill :)

It was also a bit short for my spools.

So I made a new one, following similar lines in design, like the double sided base (same part on left/right) and aiming for a strong enough holder, but a bit lighter on plastic usage.

It's a bit taller, with a little over 12cm total height, and a litlle over 7cm width.

I has a bit more grip on the axle area, for a good fit on an 8mm axle.
I used a threaded steel rod with wing nuts and a spool adapter (as pictured), but the wing nuts forced the bearings center to the inside and it binded a bit, so I made a remix of a spool roller, and it worked out great: http://www.thingiverse.com/thing:1763377

The base is only 3mm height, but I made it solid in Slic3r settings, and it has holes for 3mm bolts, but they can be drilled to 4mm.

It can also be bolted to some wood bas