Homemade hatch cover for the Looksha Sport LV

The kayak has a hatch aft of the cockpit, but there was no hatch cover, and I couldn't find a replacement.

Hatch cover number one.

The inside of cover #1.

 The first hatch cover was made from an exercise ball that I bought at Urban Ore to make into a flotation bag.  It has a skinny inner tube glued into the rim of the cover; the tube was cut to a bit more than the circumference of the hatch, one end was glued shut, and the other end has an NRS air valve.  (The valve is glued into a piece of vinyl tubing, which is jammed onto a PVC hose barb, which is glued to the end of the inner tube.) 

The idea is that when the inner tube is inflated the cover tightens around the hatch rim and seals it.  It seems to work, but the tube has a slow leak and the cover becomes loose after a few minutes.

I made a second cover from part of an air mattress that I had cut up to make a flotation bag.

The second cover on the hatch.

The inside, with a temporary coroplast insert.

It has another inner tube glued into it, and this time I checked the tube carefully for leaks first.  It still needs a valve (the white thing on the tube is a hose clamp that doesn't work too well), and the edges have been left untrimmed to make it easier to wrap a bungee cord around it as a temporary fix.

(Update, October 2012:  The hatch cover I've been using the last few months is a sheet of 1/4" marine plywood shaped to the hatch and covered with a rubbery plastic material that's held on with a a loop of elastic cord around the outside.  This has an 8" plastic deck plate in the middle, which makes it easy to get stuff out of the hatch from the cockpit without removing the whole cover.

This setup is heavy [and kind of ugly] and I'm thinking of making a fiberglass cover to replace the plywood, and adding a fiberglass rim to it to secure the rubbery material, which is difficult to glue to anything.)

(Later update: a fiberglass cover would have been fairly easy to do, maybe with part of a refrigerator door gasket, or a car door gasket, to make it somewhat water tight.  I don't really like working with epoxy and fiberglass, so I might try a neoprene cover made the same way as a neoprene spray skirt.  I can document and post it here if I think there's any interest.)