Hi @Jhans
We have been using the T200 for years in salt water, with intensive use, almost daily, especially in high season since we are a tourist project.
The first T200 that we used(5 years ago), rusted a lot and we had this problem quickly. With the newer thrusters, which are better encapsulated, this problem has been minimized.
But an essential procedure that has helped us significantly reduce this problem is the following:
- obviously sweeten a lot
- (after sweetening) activate all thrusters for about 5 seconda, resting the ROV on all four sides, face up, down and to the side, repeating the process.
By doing this process, we remove almost all of the water that accumulates on the rotors, which in my opinion is what causes most of the oxidation through scratches that occur on the rotor magnets. If we are not going to use the ROV in a few days, the next day we repeat the process again so that they dry completely.
In my opinion, this problem is due to the friction that occurs in the rotor magnets with external agents, such as sand, which scratch the paint protection and expose the magnet to the elements. Therefore, removing the water helps slow down the problem.
Another thing we do, when we see friction or resistance when turning the propeller by hand, a sign that the oxidation process has started, is to disassemble the rotors, remove the rust and paint the magnets with a small brush and epoxy. Thus we create a new protective film that again extends the life of the rotor.
By doing these steps at least we have tripled the life of the rotors.
I hope I have helped.
Regards