Propeller Mounting Case for 2mm shaft DC Hobby Motors

thingiverse

This is not going to be waterproof, but if you seal up the hole at the back with epoxy/hot-glue and pack the motor shaft hole with grease you may get some time with it in the water before it leaks and ruins the motor! :) Use at your own risk. The different sections glue together with epoxy. Make sure you don't use too much solder on the motor wiring or it won't fit in. No mounting points, these were just attached using cable-ties. Update: this has had three submersions in water for a few minutes each and no water leaked in through the silicon grease. Obviously for long periods of time or under pressure this won't be the case, but I'm pleased it lasted at all! :)