Inject a deck for soft spot repairs

[ageless]

I saw that--If I hadn't already purchased a kit I'd be all over it

 

[Vitamanseasalt]

Gorilla glue is an alternative

Gorilla Glue messed up my boat, when you start moving around it loses adhesion and moves around inside the laminate and the soft spot starts "trampolining." The whole area sank. No way to get it out. So I tried to add a two part foam to it and it was uncontrollable and powerful, it bulged the deck, a soft bulge too.
Dont use Gorilla Glue!

 

[Vitamanseasalt]

On the sidedecks at the cockpit and the house cockpit wings/flying bridge supports we used Hilti fire foam. Good luck getting it off any surface it comes in contact with. The cockpit side decks were rodded out with fiberglass electricians snake, blown out with compressed air and then on the hilti spray gun we added vinyl tube. The vinyl tube was able to be snaked into the deepest recesses of the side decks and as we sprayed the foam just pull the vinyl tube out a little. I got pictures of foam coming out of every orifice! Pushed the lower skin down a little but who cares on the side deck. The cabin flying bridge supports I made several braces to keep the foam from expanding the two skins apart. the wings had the foam cut back 1.5" inside the skins and then that area filled with thickened epoxy as the cap. It all worked perfectly. I cut back the foam around the rod holders and filled that area with thickened epoxy so the bolts could actually clamp tight.

I tried that, from your post, that's the stuff that bulged everything, DON'T USE FIRE FOAM! You'll be sorry

 

[Vitamanseasalt]

I had a friend that bought a 53c for charter service the only area was the cabin top/bridge floor. We drilled a bunch of holes took a bent nail on a drill and scarfed the balsa out underneath. Used the great stuff non expanding foam and filled the holes with resin. He used it 10 years in daily charter fishing and it was still solid. These boats are so overbuilt I don’t think it’s a structural problem in most cases

I used great stuff and a new locktite foam and it doesn't spread so I kept drilling. The great stuff eventually turned into a sponge. I would not have known had the boat not started listing a little on the repair side. It rains constantly here.

 

[Vitamanseasalt]

Anyone ever check with a moisture meter the before and after trying this foam method? I imagine it still reads wet after the foam, depending on how much wet core is removed.

The surveyor told me to try Injectadeck but I tried cheaper products instead. The mistake was prolly following the Injectadeck instructions but using other foams and glues. I got no "spread" the stuff couldn't get past rotted wood bits. The moisture meter still went off, the surveyor said I need a Hydrophillic foam not a hydrophobic foam or glue (Gorilla Glue was another disaster) to just buy the injectadeck stuff.

 

[Vitamanseasalt]

I used it a couple of months ago to fix a large soft spot on my foredeck. It worked pretty well, not as good as recoring but pretty close. I figured I didn’t have anything to loose, if it didn’t work I d have to rip the deck anyway….

Not cheap though, it s pretty much expansion foam with a fancy mixing nozzle

That's what I say but the crack foam and Glue didn't work and made things worse. I made sure I didn't buy the kind for lifting concrete. I may have to just replace the deck. I should have just bought the stuff after reading the internet, lots of positive results with it.

 

[Vitamanseasalt]

I should have explained better - this is a product of convenience that mixes the 2 parts so you don't have to do it in a cup. You can just squirt it right in without all the mess and waste.

On the other hand, 10 pound two part foam is only 50 bucks per quart at Marine Supply. To squirt it in, I always bought those big syringes you use to inject a turkey on Ebay very inexpensively. So, if you're a cheapskate like myself, you can do it the messy way for 50 bucks.

Im a cheapskate but it didnt work, made things worse, noone warned me about the staining.

 

[Vincentc]

I've used 6# density 2 part closed cell polyurethane foam from Jamestown Marine to to replace the wood inside the fiberglass stringers of my vintage 1983 Wellcraft 25. It is amazing/frightening to see what termites can do to wood on a boat.
I drilled multiple 1.5" holes in the fiberglass stringers and then flushed out the rotten/digested wood coring with a pressure washer. A shop vac set to blow worked to dry out the interior of the stringers.
You can buy 50ml syringes cheap on Amazon. I mixed the liquid foam in 120ml batches in plastic cups and then used a syringe to squirt the liquid into the voids. The foam does not stick to the plastic syringes, so they can be used. I have since discovered USComposites.com which has 20# density foam which would probably be better. I tested the 6# and after expansion and cure seems to have the compression strength of balsa wood.

 

[Timeless72]

Vincentc - this is almost identical to my project on a Wellcraft Tropez years back. While it took an entire summer of love and labor, I sold that boat bone dry and much better than new. Scooped hundreds of pounds of wet core out of the decks and stringers. Looking back, I would never do it again but wanted to learn and could park it in my front yard.

 

[Vincentc]

My dad often said "I did that twice, my first and last"
Owning old boats leads to new and interesting projects. Often time we not only learn how to do something you've never done before, but the impracticality of doing it.