Summary Changeable width, poor man's spool holder. I didn't have enough bearings hanging around the house so I invented this cheap version of a bearing. You will have to have 1/4"OD tubing. Mine is airline tubing, but you may have some left over from installing a water filter or you can get it from auto parts store or hardware store for like $0.39USD per foot. You'll need less than 4". Need: 4, #8 screws about 20mm long 4, #8 nuts 4 pieces of 1/4" tubing cut to about 12mm or less. Cut to fit after printing. The printed parts. Cut the tubing to fit loosely in the slots, lube it with some teflon spray or household lubricant and install the screws. You may opt to leave out the two bars for support, they are not really needed, but I use them so the rollers don't fall over from my clumsiness.