This is a CNC-able filament spool for holding loose rolls of 3D printer filament. By cutting more of the wooden washers, it can be made wider. We cut this one in 18mm MDF and use it to hold Diamond Age Solutions Ltd. http://diamondage.co.nz 100m x 3mm PLA.
Cut from 6mm-18mm sheet using a 4mm - 6mm router bit (1/4" should work). On each slot in the wheel arms, sandwich 2 small wooden washers and secure with 8mm (or 5/16") bolts or threaded rod, washers and nuts. One large washer goes on each side of the spool when it is on the axle to prevent the bolts snagging in the side of your 3D printer.
To load, undo the nuts on one side, remove the side of the spool, and put the roll inside. Replace side, do up nuts, slide fastenings so that the wooden washers hold the roll in the centre of the spool. Tighten nuts, thread on your printers spool holder with a large wooden washer on each side.