I have a 20 year old fishfinder that used to sit on my long-gone bass boat. When I recently bought a Hobie Outback it seemed the perfect vessel for the old timer (no, I'm not cheap, just really, really, really frugal.) I didn't like the idea of drilling holes in my new toy and mounting the finder permanently especially since on longer trips I cartop with kayak upside down - lots of chances to knock off a permanent mount and cause damage to the kayak. My solution was to rig up a friction fit cup holder mount that is quickly and easily removed and stowed with the battery in a foam box under the forward hatch. The friction fit part consists of a short piece of 3 inch diameter PVC. 3 inches is the inside diameter - the outside diameter is a little over 3 1/4 inches. Since the cup holder is a little less than 3 inches in diameter, I cut a 1 inch vertical slice out of the pipe. This allows you to squeeze the pipe and slide it into the cup holder. The rest of the mount is made of 3/4 inch exterior ply. The finder mount is screwed to the little platform and off we go. So far it has worked great. I mounted the sensor inside the hull right under the hatch just in front of the seat using silicone bath caulk. The sensor cable and power cable come up from the front hatch and the hatch lid closes over them with no problem. I haven't been out in any heavy seas with this rig yet but I don't think I will have a water penetration problem - the wires just kinda sink into the rubber hatch seal and it seems water tight. The pics should clarify.
