I searched through this forum and didn't find a clean answer. I've opened an inspection port in the deck of my laser and fixed my leaky mast step. Now to attach the inspection port hardware i assume I will need to make a nice silicone seal around the port and screw into the deck... The question I have is what screws should I use? Stainless wood screws or similar? I figure I need to seal them up as well with silicone when I put them in. Am I missing anything?
Since you have an opening to easily attach a washer/nut, I always feel more secure knowing that there is a nut/locknut or something on the end to prevent stripping or pulling out. Machine screw/SS with washers is a very good option. You can even go overboard (pun intended ) and add a piece of backing material to adhere to the undersurface of the thin fiberglass deck to beef it up. Although, I haven't heard of many, if at all, inspection ports just ripping out from sailing. Maybe that is because the 4200/5200 used to seal them in place is probably what is primarily holding them in place better than the screws.
It seems a lot of places on the internet (they must be correct, if it is on the internet) say to use 5200 as the adhesive and sealant. Let it set up and then add #8 stainless machine screws that are 1/2 inch long. The screws are there mainly to keep the port from twisting when tightening and loosening the hatch - not necessarily to hold the port down.
Late to this thread, but don't use 5200 because it will make removal of the port very difficult. All you want is a good (waterproof!) seal.
A silicone sealant will be fine.