I made this because the plastic washer on the electric lawnmower got worn out. They wear out from hitting rocks and tree stumps and they are designed to go out first instead of causing further damage. Instead of buying a new one, I thought why not print it?
This is still a work in progress. The first one is probably a better fit. It was taken from measurements from the broken part. The second one is closer to the actual shape, but it took alot of grinding with a dremel to get it to fit. We will see how long it lasts.
Credit to John from the MP Select Mini facebook group for the help with the design.
Edit: The file with the square edges seems to be a better fit.
Edit: Both versions broke into pieces immediately upon starting the mower. PLA seems to be too weak. Need to print in a stronger material.
I added my own supports to the second version. The first version should fit right in place, but I haven't tested it. If you print the first version you might want to add some supports or set Slic3r to auto generate them. You could also try printing it sideways, but with a raft so it doesn't get knocked over.