Filament spool bearing

I wanted to mount filament spools on a spindle so they spin freely. I use a half inch wooden dowel as a spindle and National Bearings A-1 bearings, which were the smallest bearings I could get in a local auto parts store. The spool bearing parts are as follows:

bearing_housing_inner - Slips over the spindle and stays stationary. Inner part of the A-1 bearing slips onto it.
bearing_housing_reverse - Outer part of the housing ("reverse" means that it's upside down from my original design). Out