Water proofing a Project

[John Gutmann]

First of all as an idea how about an off topic technical forum for random mechanical, electrical, and programming questions that have no relation to FIRST? LIke the Chit chat but pure technical threads.

Ok, my main point. The other night I was at a friends house when she was showing me the lighting in her pool so I had the idea of making little floating lighting elements. The problem is that I would like to make them totally submersible so you could just leave them in the rain and not worry about how you get them out. The problem is I want to be able to make them so that I can change the batteries in them. So it would need to be some type of box. I was thinking of maybe of just casting the actual control board or whatever I choose to do for the control (whether it be a micro controller or what) is some sort of non conductive resin but then I still have to worry about the battery. Then I though of using vacuum bags, but they are pricey, then I thought of the big sheets of laminate for text books but then how do I seal the box and what if water gets under the laminate?

Do you guys have any ideas?

-John