Alternative to A&B foam

[studlymandingo]

Re: Alternative to A&B foam

The spray insulation is a two-part foam. It is mixed by the gun as it is being sprayed. However, it is a very lightweight foam, and would not give the structural rigidity you are looking for. It also is probably not a closed-cell foam either, leaving it open and very sponge-like. Not qualities you want in the bottom of your boat.

 

[Chief101]

Re: Alternative to A&B foam

Originally posted by studlymandingo:<br /> The spray insulation is a two-part foam. It is mixed by the gun as it is being sprayed. However, it is a very lightweight foam, and would not give the structural rigidity you are looking for. It also is probably not a closed-cell foam either, leaving it open and very sponge-like. Not qualities you want in the bottom of your boat.

The spray foams come in many forms and the best of the best foams come in spray form. I would select the medium weight foams(7-8#) over the lightweight versions(2-4#) for permenant floatation as the heavier ones tend to repel water much better. Chief Chief

 

[ondarvr]

Re: Alternative to A&B foam

Mohawk<br /><br />This isn't directed at you, but why would you fill a water tight blue plastic 55 gallon drum with plastic bottles? I use the blue drums under my dock without plastic bottles and have had no problems.

 

[Chief101]

Re: Alternative to A&B foam

Originally posted by Mohawk750:<br /> Thanks for the link guy's.<br /><br />Everybody likes US composites. I talked to a local supplier and he told me about a guy who floats his dock on blue barrels filled with soda bottles.<br /><br />I believe that it's possible to get floatation from alternative's but only the poured foam will give the structural rigidity and floor support that I would like. I think I will use it but seal all the wood under the floor with resin and provide allot more drainage options to get the water to the bilge.<br /><br />There are companies that do spray foam insulation in commercial buildings. I’m wondering what kind of foam they use and if any one has taken their boat to one of these guys and had them spray the floor full before closing.

I like the spray foam and I might use it in a boat I am rebuilding now. The foam I would use is 7# and extremely water tight. I could find out what exactly it is if you wants to check it out. Chief Chief

 

[mckeemm]

Re: Alternative to A&B foam

andver,<br /><br />I guess he was thinking that if the blue barrel sprung a leak he would still have a hundred sealed floats inside.<br /><br />All,<br /><br />I'm going to call around and see if anyone local can give me info on the spray foam. If I can't find what I need near by then I’ll have to go with the kits and mix at home.<br /><br />I dug the wood out of the transom last night. I was surprised to see that the wood rotted from the top down, not the bottom up. Some of the wood still had a good bond to the fiberglass; I managed to get it out in four big pieced and half a garbage bag full of..ahh....compost! Made my first boo boo too. I was a little aggressive with my saw kerfs when I was hacking out the transom and plunged the blade nearly through the fiberglass for about 6 inches. I'll have to do a repair before I lay the new transom in.<br /><br />Going to look at a used outboard tonight, a little small for the boat but the price is right. I can always move up latter.<br /><br />Mark

 

[Paddy3101]

Re: Alternative to A&B foam

Whilst I am replacing the transom, I have dug out the foam between the stringers at the stern. All of it was completely saturated. There are no dains between the stringers to let anything drain into the bilge. In one compartment, the foam was wet with Petrol! Probably non neat, but enough to burn (I tried it!) Not sure how it go there, the boat has had a few previous owners, but I'd much rather it had drained into the bilge and been pumped, rather than sitting there suspended in the foam.

 

[Purduebarry]

Re: Alternative to A&B foam

Air is an insulator. Most of the expanding foam for packing and insulation are full of air bubbles. I'd be very leary. If your going with foam I'd use the stuff intended for flotation. Open cell vs. closed cell is the main difference. If in doubt ask who supplies the base materials. Most of the chemical companies have product engineers who can answer these questions. BASF, DOW and Dupont are the leading suppliers of this stuff. Call em up before you commit.