SpaceSpool - A lightweight MasterSpool

This is an expandable 'MasterSpool' style printable spool.

Called the SpaceSpool, the design requirements were as follows:
Must be lightweight
Must be expandable to allow for 1KG refills to be used
Must work with both 1.75 and 2.85 filaments
Must be easy to print with larger nozzles
Must be available for commercial use to allow for adoption by filament refill manufacturers.

Weight:
24g per rim = 48g per x2 rims
29g per half core = 58g per core
Total weight = 106g per spool

Features:
Prints in four parts which are secured using filament or zip ties
Works with all filament sizes
No hard to print features
Can be printed with large nozzles 1mm+

Two Versions:
The Original SpaceSpool which follows all masterspool guidelines and has a reduced inner diameter for spool holders that use the inner surface as the contact point
The Saver SpaceSpool which removes most of the inner core to save on filament weight. This version is meant to be used with 'roller' style spool holders (TUSH), but has a smooth inner surface so it may work with inner contact holders too.

To encourage improvement I am uploading .STEP, .F3D, and .STL files so users can make their own changes if they find something lacking.

NOTE: This is an untested WIP, pictures and testing will follow.

UPDATE 9/12/18 - Added V2 after initial tests showed tolerances were too tight
Tolerances between alignment tabs and holes increased to .4mm from .25mm
Chamfers added to all bottom surfaces to enable easier printing and reduce 'elephants foot' presence.
Increased lock pin hole from 2mm to 2.5mm, and doubled it's width to hopefully make inserting filament easier.