Spool axel holder for anet A6 and A8

This is inspired by 2 other similar designs but designed to use the bearings from the Anet A6 and A8 kits. I had some left over after I replaced them with quieter bearings. In addition to that, I increased the spool compatibility.

It is compatible with spools from 25mm to 85mm and fits 15mm diameter bearings.

I, however, don't think I know how this type of design is supposed to be used as the entire bolt rotates together with everything else, rendering the bearings pointless and if the bol