Electric surfboard - dual motor direct drive. Few Questions


Hey E-foilers, I’ve been researching some ideas for my electric surf build and then came across this forum, its absolutely awesome what some of you are building, and great that pacificmeister started the forum!!

For my surfboard I’m going to be using 2 6364 190KV out runners https://hobbyking.com/en_us/kd-53-30-high-voltage-brushless-outrunner-190kv.html that will be fully submerged, directly driving the props (which I haven’t fully decided on yet). This will be on a small surfboard with no foil.

I just wanted to clear some things about preparing the out runners for maximum life length undertake water.

  1. I will be using epoxy on the motor, so will any 30 minute epoxy work, or is there a certain one to use?

  2. When putting the epoxy on the stator would it be fine to not use a vacuum system, but apply it by hand and force it into the motor? my main aim for using the epoxy is to help strengthen the windings from all the water running over them - which would eventually wear off the enamel coating, and stopping the magnets from rusting.

Some more about the rest of the build:

It will be running on 12S li-po, with 2 of these ESC’s https://hobbyking.com/en_us/yep-120a-hv-4-14s-marine-brushless-speed-controller-opto.html which with the active freewheeling can take high power at low throttle without overheating.

My idea for the propellers might be stupid but Ive bought got some big wood Radio control plane propellers 2 with 20 inch length https://hobbyking.com/en_us/turnigy-type-d-light-wood-propeller-20x6-1pc.html , and 2 with 13 inch length https://hobbyking.com/en_us/turnigy-wooden-slowfly-propeller-13x4-5-ccw-1pc.html , I plan on cutting these down until I get the most efficient mix of power and amp draw. The blades on these are a lot thinner than the ones you use on yours but its worth a shot. Any better ideas?

Ill just be using some metal brackets to mount the motors to the surfboard at this stage also

At this stage a battery configuration of 10Ah 12S.

Ill be sure to post some progress of the build here.

Any advice would be awesome!

Thanks Everyone!!


Here you find some description on epoxying motors:

The propellers have to be much smaller. I would recommend 50-120mm for these motors.


@PowerGlider, yep I realise those props are way to big, I plan on cutting them down a lot haha. Do you think that the blades on the wooden propellers are wide enough?

Thanks for the help.