I build a Mendel90 from a kit by nop head. This kit included a spoolholder, but only for a particular type of spool (narrow and large radius) which nobody seems to sell around here. So I designed this universal spool holder. I couldn't be bothered to get any vitamins, so I made it fully printable, meaning you don't need any extra parts and it'll just snap onto your printer! In the meantime I've been using it for a couple of months now and it works flawlessly. The spool slides over the holder with very little friction. I've also made it customizable, so you can make it fit onto your 3D printer.