: My Beckson hatches have sealed well using Aquaseal. Clean both surfaces with
: alcohol and lightly sand. I also used small screws with a 1/4" backer
: plate on the inside of the deck.

Ill have to use screws then. The small 4" I got was without the pre-drilled holes, and I liked the look, so I just glued them in place and filled the holes (on the 6" hatches) with black goo.
I just liked the cleaner look, as well as having no screw-holes penetrating the wood.