One last job before a return to the lake, make a buoyancy aid for the Ark.
My theory is that if I fill the hull with polystyrene, it can't fill with water. This might not save it on its own, but if it does start to sink, the sinking will be less dramatic and I can charge the bank to get within rescue distance.
To aid this, the receiver is sealed up in a plastic bag. I can't protect the motor or servo, and the speed control can take a dunking, but it's all about increasing survivability.
The foam is hacked away using a sharp knife (messy) and hot wire (clean, but limited use due to access issues). I kept pushing down on the foam to mark where I should cut next.
Fingers crossed I don't need this...