Best way to fix rotted wooden seat backing

[Swan]

I even coated mine with a little flex seal I had left over . measurement dont have to be dead on . its got to fit between the hip restraints and the rest can float a little

[Mooncarter]

I have one like that in the ghost fleet but it's pretty rotted to. Sorry I can't get dimensions.

[meimk]

We've been using this plastic. Not too far off the price of decent plywood, but it will never rot.
https://www.homedepot.com/p/Veranda-...4808/301950563

[mrshosted]

If you have settled in on using plywood? If so, Id use a marine grade plywood. it may cost more, but in the long run it will last much longer.

[cohen]

Wanting to bring this full circle for anyone searching for this later. I did use marine grade plywood 19/32” thick and was able to salvage the foam so I traced out the foam block on plywood then cut it. Roughly was about 37.5” x 15.25”. Next I laid in the plywood where it was mounting and marked the 8 mounting holes *(set seat about 1/8-1/4” forward, off the bar of flip down bracket, to account for width of foam and seat wrap) and drilled/installed the wood inserts on the top side of wood so the mounting screw hardware pulls it into the wood. Then put foam on *(thicker part toward back of your knee when sitting) wrapped the seat in my sweet new seat cover vinyls.

*Lessons learned:
1. Should have moved mounting holes about 1/8-1/4” back because when I wrapped seat it squished foam outward and the vinyl seat wrap both make it wider a little hard to get the screws installed to wood inserts.
2. The foam top is slightly thicker on one side than the other so you want the thicker part of the foam at the back of your knee so the seat naturally wants to keep you back in the seat. Versus if it were vice versus it would be wanting to dump you out of the seat- if that makes sense...

[handtools]

Looks Good!