50mm Spool Support For Hypercube

I am building a Hypercube printer, and needed a mount for a filament spool, so this is what I came up with. It may be similar to some others posted here, but I designed this from scratch.
The spindle has two 608 bearings that run on either an 8mm or 5/16" shaft. Amazinglly, they only differ in diameter by less than .001 inch. I used a 6" long piece of 5/16" rod that I threaded 5/16" UNC on one end. You could also use a 5/18" X 6" bolt also.
You will notice that the mount has a slot and a boss