I Needed a 5mm pinion gear while I waited for mine to ship. It's very tight around the shaft, you might want to drill it out a bit larger or remix. I haven't run it yet as I only printed a test part to fit. I would suggest abs probably. I'll post more pics when I run it and we'll see how long it lasts. 100% infill no supports.
The author marked this model as their own original creation.