I needed some spools for various wire I had laying around so I whipped these up in Sketchup. They are all 70 mm diameter and come in heights of 60, 50, 40 and 30mm and should scale well too. I figured I'd upload them in case someone has a use for them too. I used abs glue to attach the top, but you can use whatever you like. Print the size you want and use the one top for all sizes.