Roller bearing for Inland filament spools

I use spooless filament from Microcenter but often it's out of stock. To their credit, they will sub a spooled roll at the same price, but the large center hole of their spool makes it drag when I hang it on my 1" holders. Using Brien Allison's excellent bearing scad as a base, I made a slip in bearing that fits snugly in the Inland cardboard spools and slides onto the 1" rods I use. Cuts the drag to nearly nil on my TPU spools to... 

Prints in place using no supports or additional hdwr, use .3 layer, 15% rectilinear, and it'll print in about an hour depending on your settings… flathead slots in the rollers to make it easy to break loose and use right away.