Hi Paul

: The simplest waterproof switch I've seen was built by a friend in college for
: operating an underwater housing for his camera. Since he did not want any
: holes in the housing, which might leak, he used an inexpensive magnetic
: "reed" switch which was sealed inside the plexiglass housing
: with his camera.

Yes, I looked at these also. The only ones I could find would only take an extremely small current, a few milliamps.

I also looked at the ones used for home security and they were also only able to handle small currents under 1 amp.

Radio Shack is getting out of the repair end of the electronics industry. It seems no one wants to spend $50.00 to fix a device that only costs $59.99. GO FIGURE!!

: A reed switch very simple and reliable. It is a sealed glass tube with two
: wires inside it. The wires are mounted close to one another in a vaccuum
: and a small magnetic field will cause them to flex and touch. Depending on
: the thickness of the wires used on the reed switches these devices can
: handle substantial current.

Yes, I had thought of these first but I need a minimum 2 amp switch at 12 volts and these were rated to a few milli-amps at 12 volts.

I also thought of using a relay to control the pump and a low voltage circuit to trigger the relay. This way I could have everything sealed into the batterybox and build the reed switch right into the kayak by enbedding it in epoxy on the underside of the deck. A little complex but reliable.

I decided to try the regular toggle switch first simply because of ease of building and the fact that the only problem is to seal the switch. If the rubber caps work, which by looking at them, is very likely, I should be able to build the whole thing in a matter of minutes.

: A magnet on the outside of the housing turned things on and off. He used a
: rectangular magnet, and made a track out of plastic strips which were
: glued onto the housing. The magnet could slide to either end of the track,
: but could not come out of the track and be lost. It worked fine through
: 3/8 inch thick plexiglass.

I will keep this in mind. This was one of the problems I was looking at solving with the low voltage relay circuit and this is a good way to solve it.

Thank you for your input,

Ian