Interesting.

Last night I met a local kayak builder at the pool session. He had his Petrel with him this night. I asked him how he fastened his KayakSport hatches to his Petrel. He set them in a bed of thickened epoxy. Strong. Tight. No problems. I mentioned my quandary and he wondered why I was a bit hesitant about using the epoxy. I explained that at some point I may need to replace the rim. His response was that if you need to replace the rim (which he thought was unlikely) simply cut out the existing rim and plywood base, and replace the whole lot. In actuality, this would not be a big deal.

The reason I ask about the viscosity of 3M 5200 was because I'd like to set the rim in a bed of adhesive that would settle out nice and smooth so that I could paint it the same colour as the deck. One consideration, of course, with epxoying the rims is that you need to rough the underside of the rim so that the epoxy will adhere to the plastic. I'd do this but I also have some G-FLex that might work well here.

I would've simply used the bolt and seal if I had not've seen a plastic valley boat in a local outfitting shop that had the rims fastened without bolts. That set me to thinking . . .

: The problem with screws is that they ultimately cause the rims to
: split, unless you leave them just snug, in which case they're
: prone to leakage. IMO, it's better to just clamp the hatch ring
: in place while the sealant cures and leave the flange intact.
: The only reason you see screws on commercial boats is that it
: speeds production.