I think I mentioned the issue of the hull going hot and cold over the weekend and water being sucked into the boat. I believe it was getting sucked in through the top of the radio pot because there was no seal. To the rescue came our winner Tony, with a disk of 2mm thick EVA foam which formed a nice seal in the top of the radio pot. It was so good, when I took the lid off the pot, the EVA foam was sucked into the radio pot but more important no more water in the hull.
I found a supply on Amazon so if you need any, that is where to go. Look for EVA foam sheets, 2mm thick, A4 size, 10 sheets in a pack which should keep you and your club in sealers for a season. All you have to do is cut them out.
It is the small details that make a difference.