: I am curious, do hatches spring back from the deck shape when removed? Also,
: can you reinforce them before cutting them loss?

It would be tricky to reinforce them before cutting them out, but depending on your access to the hatch area it might be possible.

You would have to know the exact place on the interior of the boat to glue your reinforcing strips.

You'ld normally drill a few holes on the cutting line in order to have a spot to start your cutting. If you make those holes in the right places you can use them for aligning your reinforcements.

One way to do this would be to draw the outline of your hatch on the outside of the boat, then decide where on the inside you would want your mini-deckbeams or reinforcing strips. Lay out those lines on the outside of the deck, too. (A grease pencil or china marker should work nicely on your epoxy. You can remove it with a swipe of a solvent laden cloth.)

Drill a small hole in the line you would cut on, where it is intersected by the line you want your reinforcing piece to be. Then drill another hole on the opposite side of the hatch, again keeping it in line with the proposed location for the reinforcement. If you are putting in two reinforcing strips, you'll drill 4 holes.

Now, when you stick your head inside the boat you should see tiny dots of light showing where those reinforcements will go.

You wamt to make the reinforcements shorter than the width of the hatch so they don't interfere with the hatch lip you'll be putting in later. You cna get the length for this by measuring the distances between the two holes. If your lip is going to extend in 1/2 inch from each side, make your reinforcement at least 1 1/2 inches shorter. this allows for learing the hatchlip and gives you about 1/4 to 1/2 inch of slack in case you don't get the thing glued in EXACTLY the right place. Stick a chunk of wood in which is the right length, and scribe the necessary curve on it, then when they fit you can glue them in. A length of thin wire passed through the holes you drilled can be used to hold the reinforcing blocks in place until the glue sets. If you use epoxy you won't need to apply significant pressure.

When all the reinforcements are glued in and the glue or epoxy has hardened, cut out the hatch, cutting right through those drill holes, so the kerf of the saw blade obliterates them.

hope this helps

PGJ