Thanks for the reminder.
The pic is of the partially made fitting that will eventually go inside the hatch. The insert sitting on top is made from 2 layers of 5mm corecell foam with a rebate to ensure it is located at exact height in final fitting. It still needs to be sanded and top shaped to match the underside of the hatchand looks pretty poor at this stage but will look right when finished.
Once this is done it needs glassing and this will be done in two steps. Glass the outside while it is in place in the lower fitting with packing tape being used to afford a release so I can make a flange for later glueing together. Then glass the inside. A neoprene seal will be fitted to the top edge.
Keeping it in two parts until fitting beacuse this allows me to tape the lower fitting in place before adding the insert. This is the only way to get access where the flat section meets the hull. Prior to adding the insert would also be the best time to drill the drainage holes.
Any water that comes in the hatch will go into the channel formed by the fitting and exit via drainage holes.