under deck foam

[jeep94]

Does anybody know where I can get the foam that was under my plywood floor in my baot? Or is there anything else I can use instead?And the price. Im re doing a 19 ft. baliner from 1987 and all the foam was saturated.Im ready to put the floor back in but I need foam. Any ideas?<br /> Thanks guys!

 

[RTW2112]

Re: under deck foam

 

[Boomyal]

Re: under deck foam

I thought that you were supposed to use a two part closesd cell polyurethane foam?

 

[JasonJ]

Re: under deck foam

USComposites.com, you will probably need three 2 part kits, they are forty something per kit. Great Stuff will absorb water, I tried it. I tried everything to avoid buying the two part, and ended up getting the two part. Even the two part closed cell foam could take on water, but it would have to be exposed continiously for years.

 

[Hooty]

Re: under deck foam

The deal with two component urethane foams is the mixing ratio is very critical. If the ratio of component A to component B is 1:1, it has be be exactly 1:1. This means that, even if the two are measured precisely, the one component left sticking to the side of the mixing container, unmixed, will upset that ratio. That's the reason so many boats with inplace foam wind up with open cell foam in the bottom.<br /><br />c/6<br />Hooty

 

[RTW2112]

Re: under deck foam

 

[jeep94]

Re: under deck foam

I'll tell ya that 2 part stuff isnt cheap!! Can I do as bayliner did? That is put all the decking in then bore holes for the foam to be bored in? If I use the stuff in the can it will take cases of it to get the job done. <br /> Thanks for all your replies guys and the help!<br /> Eric

 

[Link]

Re: under deck foam

I don't mean (yes I do) to be doom and gloom<br />here but the "Great Stuff" home repair stuff is<br />good for home repair! Not for a Marine repair!<br />Take a small peice after cured and light a match<br />to it! Then add gas and oil to it! There is a<br />reason why 2 part closed cell foam costs so <br />much.. being cheap I've tried the stuff! <br />Listen to what JasonJ has to say.. <br /><br />Link

 

[RTW2112]

Re: under deck foam

 

[mellowyellow]

Re: under deck foam

RTW... what he is saying is that great stuff is<br />flamable, 2 part marine isn't. no need to get<br />your panties in a bunch...

 

[RTW2112]

Re: under deck foam

 

[CCrew]

Re: under deck foam

"" Tell me smart guys: what EXACTLY is the difference between a one part closed cell polyurethane foam and a 2 part closed cell polyurethane foam"<br /><br />Well, heck. That's easy..... 1 part!

 

[jeep94]

Re: under deck foam

Ok guys, Idon't wear panties!! But bayliner never did the boat right to begin with.... deck was never screwed down to the stringers... sealer was not used at all on the underside of the decking.... But I don't want to bash them... I Love the style of this boat.. the tinted glass the sleek look, I just want to do it right.I'm a mechanic and I do like to make it right, but if I save a buck Im gonna.Just wonderin if its right.All thiss bickerin and I'm begining to like this site!!! Thanks for all the help Guys! Sorry I a soar subject!!<br /> Eric

 

[RTW2112]

Re: under deck foam

 

[CCrew]

Re: under deck foam

jeep94,<br />Is it an 87 Capri? I'm getting ready to rip into mine, and would love to have some insight from somone that's "been there, done that". Thanks!<br />Roger

 

[RTW2112]

Re: under deck foam

 

[jeep94]

Re: under deck foam

yes mines an 87 capri 19 ft. sorry to say but bayliner did throw em together back then. But I love the style. Real sleek lookin. So I'm tryin to do it right. Got this thing for only $600.00,it needed engine work but did it all myself....I got fingers on our machine shop! LOL Like I said tryin to do it right if not better than bayliner did back then. I plan on keepin it a while.

 

[JasonJ]

Re: under deck foam

If you want to use Great Stuff, use Great Stuff. Its your boat. I recomend you do the math first before you decide. Take the fully rigged weight of the boat, and divide that number by 62. That will give you the cubic feet of water that needs to be displaced, and also accounts for the weight of the foam itself. Take your under floor volume and calculate it for cubic feet. You want to come as close as possible to your fully rigged boat weight for displacement, but sometimes there just isn't enough room under the floor. Price how much cubic feet of Great Stuff you will need, as well as the 2 part foam. You get 8 cubic feet out of 2 part foam, 16 cubic feet is usually enough to keep a swamped 17 foot boat at the surface. You could go with three 8 cubic foot kits, spend about $150, and be done with it. The logistics of trying to get all that Great Stuff under the floor and having it fill properly is difficult compared to the 2 part. Lastly, 2 part foam is more dense than Great Stuff, which will give you more strength, which will allow you to use a more thin plywood for the floor, and give the boat more stiffness and prevent hooking, bowing, and twisting. Anyway, do the math, and whichever works in your favor, do it. I still stand by 2 part foam, despite its horrid cost. Good luck, and post pics of your project, we loves the pics

 

[RTW2112]

Re: under deck foam

 

[sbakf]

Re: under deck foam

Last year I had some weak spots in my boat's deck (1976 AMF SLICKCRAFT), so removed about 60 sq. ft. of decking to discover a lot of water saturated foam. Also discovered that most of this water had come from rain water running down along the outside trim rail to the bow tip, entering the front cabin, running under the vinyl cushions, into a covered storage box, under what you may call a subfloor bulkhead, then down the hull stringers, which saturated the foam and subsequently rotted the floor from underneath. Hull and stringers were fine. Dug out mushy foam and replaced with GREAT STUFF (Minimal Expanding Foam Sealant). I let it cure and expand overnight, then cut off excess with a hand saw and shaped with a hand sander. In the process of doing this work, I one day sprayed some of this stuff on a concrete block in my backyard. Never removed it and to this day, having been exposed to rain, hot sun and freezing temperatures, it's still intact, hard as a rock and stuck to the concrete block like I used epoxy. I wouldn't hesitate in using it again. Just don't shoot it into an inclosed space. The expansion force is too great.