Bench seat foam replacement

Telopie · Sep 14, 2022

Hello everyone,

I am quite new to fishing and boating. I live on a residential lake with a dock (about 20 acres of navigable water). I picked up an old aluminum terry boat from a neighbor and want to restore it. I noticed when I was washing the boat out, a lot of Styrofoam was coming out from under the bench seats. I'm having an issue with deciding on how to correctly replace the Styrofoam that was in the bench seats or if I even need to? From the pictures below, that is the foam under the front bench, Do you think it is in acceptable condition or should be replaced? Looks bad to me

I've done quite a bit of research but I seem to be leaning toward the 2 part pour foam but some people say ANY kind of foam will have water issues eventually. My boat will be tied to dock and exposed to elements all year round. What would be the best way to future proof the foam as much as possible from being damaged by water? I will have a cover/bilge pump in the boat eventually.

I have only came up with one idea on how to do it which is the following and would like your opinion:

Reattach bench seat to boat > Cut a access into the top > Put a piece of clear coated plywood at the bottom and heavy duty plastic (So that the foam has no where to go except the molding of the bench seat> Pour foam

Thank you for any suggestions you may have for me.

GTS225 · Sep 14, 2022

T'were me, I'd just clean that mess out of there, measure up the cavity, and go to your local home improvement center and get an appropriate thickness foam insulation. Either the blue or the pink stuff. Grab a can of spray insulating foam, too. Cut your foam board into the correct shapes, spray some canned foam on one side, and slide it into the cavity. Do that until the cavity is full, and Bob's your uncle.
(There's probably some under that rear seat, too.)

New flotation foam, and you didn't have to spend more than you needed.

Roger

Stove Iron · Sep 14, 2022

Another option, do you want to reinstall that bench seat?

I can't tell from the photos, but are there rivet holes in the hull generated from the bench seat removal? A lot of tinboaters remove that front bench seat...no matter the size jon boat...to make more room. Perhaps you might consider installing blue/pink closed cell sheet insulation in the floor and covering it with plywood or another material.

However, one possible downside might be reduced lateral rigidity from lack of the bench seat bracing both boat sides.

Kismet · Sep 14, 2022

'Cuz I didn't know...

https://www.starcraftmarine.com/sites/default/files/catalogs/StarCraftTerryAluminumFishBoats1983.pdf

Nice water craft.

LDUBS · Sep 14, 2022

GTS225 said:
T'were me, I'd just clean that mess out of there, measure up the cavity, and go to your local home improvement center and get an appropriate thickness foam insulation. Either the blue or the pink stuff. Grab a can of spray insulating foam, too. Cut your foam board into the correct shapes, spray some canned foam on one side, and slide it into the cavity. Do that until the cavity is full, and Bob's your uncle.
(There's probably some under that rear seat, too.)

New flotation foam, and you didn't have to spend more than you needed.

Roger

X2 - this would be easier than pouring two part foam and less expensive. To prevent water logging keep the foam high and dry. Because it is up off the floor, it should last a long time.

airshot · Sep 15, 2022

LDUBS said:
GTS225 said:

T'were me, I'd just clean that mess out of there, measure up the cavity, and go to your local home improvement center and get an appropriate thickness foam insulation. Either the blue or the pink stuff. Grab a can of spray insulating foam, too. Cut your foam board into the correct shapes, spray some canned foam on one side, and slide it into the cavity. Do that until the cavity is full, and Bob's your uncle.
(There's probably some under that rear seat, too.)

New flotation foam, and you didn't have to spend more than you needed.

Roger

Click to expand...

X2 - this would be easier than pouring two part foam and less expensive. To prevent water logging keep the foam high and dry. Because it is up off the floor, it should last a long time.