The handle switch for my rototiller broke. Took a while to reverse engineer it but I did make this working model. It is still in service over a year later. I think the center pin is just a touch too tight but I sanded it out and its fine. Please unplug your tiller before attempting a repair if you do. This is live 120v (US) in that box, it will hurt you. In the photos you will find: My final printed handle, the original which I glued together temporarily for measurements, and a screenshot from Ryobi's website circling the handle.
I recommend at least PETG and pretty stiff infill (I used 20% I think?). It is in a very harsh environment outside and high vibration.
The author marked this model as their own original creation.