Bare Minimum Spool "Roller" Holder

Print from your cereal drybox. No bearings to buy and degrease. 17g of filament. I suppose this is "yet another" spool roller holder, but the existing ones a) require a good deal of filament, b) do more than just hold the spool, c) the ones intended for holding a spool while you print pretty much all require 4 bearings. This design does away with bearings and silica compartments and hydrometer holders and focuses on the job at hand: printing from your cereal drybox. Instead of ball bearings, this uses PTFE tubing as the sliding surface… you may know PTFE by the brand name Teflon, it is famously slick and I use the same stuff that feeds the filament to your printer. All you need is a few cm of worn out tubing—new works just as well, and it's easily replaced when the spool eventually saws its way through. There is no need to be particularly accurate with the length of the bits of tubing, if you get at least ¾ of the slot filled you will be fine but longer is better than too s