Thanks Tim, Good info…I am still researching, the sea rider I made uses a 6v gel cell battery, a 540 cheap buggy type motor from memory and a plastic 2 blade prop, will have to measure the size of that, but some good grounding work.
A 3 bladed prop would be better for looks when out of the water…the HMS romper I made has a ,3 blade prop…
With the advent of 2.4 radio gear all sorts of possibilities spring to mind these days, my aero 2.4 set can be used economically…working depth charges, now there's a thought.
Anyways I must be realistic, the local lake is quite choppy so water tightness is most important for now, the extras can come later.