If you know what this is you know this is an oddly specific design. I had a friend whose bobbin winder broke on her sewing machine, so I designed and made this as a Christmas present. So if you have a sewing machine that can't wind a bobbin and a 3D printer here's an alternative to fixing or replacing it. I made it easy to print and assemble.

It requires an M5x 35 or so hex head bolt with an M5 nut. Glue the bolt into the last gear and glue the nut into the bobbin holder. It also has holes for 3mm filament to stabilize the axis's. Just glue the filament into the gears. 1.75mm filament may work too or find something about that size. After printing it I noticed that there was a slight catch when rotating it. Probably when interfacing layers had filaments strands aligned. So for increased usability I think a piece of paper between the gears and container would fix that, or sewing machine oil, or put a finish on it. Or maybe there's a print setting to make the top and/or bottom layers of the gears concentric instead of linear.