The second, larger hatch on my kayak needed a cover as well. This one was going to be more complex because it is oval instead of round. Intuitively that already tells you that the tensions holding the cover onto the lip of the opening will be distributed unequally. As before we start with an old wetsuit.
Trace, measure, cut, measure again, trim a little bit, and sew. Since there’s barely any tension keeping the the long sides of the oval on the port, I sewed some velcro onto the cover and glued the matching velcro onto the boat. Pop it on, secure the drawcord in an eyelet and we’re ready to conquer the stormy seas.
I dragged her down and launched her from the beach in light surf with no apparent problems. During my peaceful paddle ’round the wharf the wind and the chop picked up. We tried to ride a small wave in during the landing. Her bow plowed deep and the overpressure pushed the new hatch cover in, flooding the kayak before I could even think up fitting expletives.
This version is a clear failure. I think it’s time to move on to the rigid HDPE sheet with clamps and glued neoprene seals.