This is my frist attempt on a motorized Grinder. Is use a N20 Geared Motor on 6V mit currently 600rpm, but i just ordered one with 100rpm. I think less revolution would work better.

My printed Version is glued together, i developed some parts, printed them and put them all together later. The Download is a ready to work Version.

It is all printable, the Rod is a 3mm square which is guided in every hole. You just need to glue the Endcaps on. For better stability you can also glue the cutting wheels on the rod. You have to mount the Rod and the cutting wheels in place. Its a bit fiddly, escpecially if you want to glue it.

I printed the cutting wheels in full PLA, works fine so far. Since my motor has so less torque it stops from time to time. So yeah 100rpm should be fine.

The gears are printed mit 2mm walls an 25% Infill. Geras run really smooth and are easy to print, just print them slower.

There are two Versions of the cutting wheels. I currently use the two bladed Version, works good, the four bladed version is not yet tested.

Hope you enjoy it, Version two is mostly done. There will be a18650 onboard power supply, a RPM control and direction switch. So you can reverse it if it jams. Also Part two has the bearings inside. The tray for the Herbs are now with meshes and separate drawers. It is a lot Bigger! New gear rate, so even less rpm on the motor needed, means more torque from the motor. 12V System to further enhance torque.