Originally Posted by thomas70
Kanani, you really should not use 5200 above the waterline the sun will break it down. And at some point the hatches may need to come out again. I've been in the business 38 years and have seen many cases where people have used it on deck
and in a couple years it breaks down and gets chaulkey.
ABSOLUTELY false........3M 5200 has the best UV resistance in the industry.
I made a very thick (about 1 1/2" thick) "Mold" of 5200 to hold a deck plate in place. My intension was to drill and screw it in place after it cured. I never did that. That was in 1990 and it is still in place with no cracks.
The plate was an access hole for the emergency
tiller. I installed a working tiller (for my windvane). The plate was not level and I installed a 5" long solid brass bearing in that plate. I slipped the bearing, plate & all, down the rudder
shaft to the deck. I ended up needing to build up the area and a shipwright friend of mine suggested 5200. It worked perfectly after curing for 30 days. I sailed 80,000 miles with the windvane
stressing that bearing (held in place with 5200) every inch of the way.
I agree that if you expect to remove the hatches again, it will be difficult. However, I would expect to not have to remove a hatch in 10 - 15 years. In that time, it won't leak with 5200, I don't think that you can expect that service
out of most sealers.
I bedded my chainplates, winches, cleats
, stansions and every other piece of deck harware that through bolted through the deck with 5200. Never had a leak.