Spindle Spool Hub holder SCAD

This is a SCAD spindle holder inspired by the Spool Holder-Lulzbot Mini by cbc in terms of design, with the 3-winged shape.
* First pass is in Spindle_Hub_v2.scad
It is parametric, this version is for a 52 mm hub, with a lip of 5mm and for a 12mm axis, but can be changed at will in OpenSCAD.

I've added external slits on the hub for togheter fit, and inner slits on the inside of the axis for axes with grooves.
* Second pass in steppedSpindle.scad has the stepped design and two