Brushless Motors

I am buying cheap Brushless Motors for my DIY ROV. I have heard online that they are waterproof, but what about particles in the water? Wouldn’t they harm the motor? If so, is there any way to protect against this?

If you’re running in freshwater, you should be ok for a bit. If you’re running in saltwater, your motors will corrode fairly quickly. You can try experimenting with coating the windings (I’ve seen Rustoleum spray paint used), or pot them in epoxy. The bearings will probably be the first to go, so whatever motors you are working with, you can try to find plastic or ceramic bearings.

If you’re running in freshwater, you should be ok for a bit. If you’re running in saltwater, your motors will corrode fairly quickly. You can try experimenting with coating the windings (I’ve seen Rustoleum spray paint used), or pot them in epoxy. The bearings will probably be the first to go, so whatever motors you are working with, you can try to find plastic or ceramic bearings.

Wouldn’t potting the motors in epoxy cause them to not spin? If you filled a motor with epoxy, how could It move?

You have to take apart the rotor from the stator. Then you basically have to create molds for each piece, pour in the epoxy, let it dry and then trim the excess away so it still spins freely. It’s a pretty painful process, so I’d recommend M100s.

SV Seeker did a bit of R&D into it: ROV Thrusters - Part 1 - YouTube I think in the end, he just bought M/T-100s.