Re: Fiberglass mat/cloth
As far as removing the stringers, I used a 4" angle grinder with a thin curf metal cutting blade to go around the deck to side joint. The same was also used for the stringers. In some areas, I used a sawzall with a long blade to slice the stringer away from the hull.<br /><br />I found US Composites in West Palm Beach to have the cheapest price so far on 2 part foam.<br /> <br />Pour Foam FAQ's from John Greer & Associates<br /><br />"Q. How do I know how much foam I need to float my boat?<br />A. Great question! Get your calculator ready, you will need it. A cubic foot of foam will float about 60 pounds of "dead weight". The wood parts of your boat will probably float, so you don't need flotation foam to offset that weight. The fiberglass parts of your boat will barely sink, so you really don't need much foam to offset the fiberglass- maybe one cubic foot of foam per two hundred pounds (or more) of fiberglass hull. The metal parts of your boat are what you really need to account for. A small (4-6hp) outboard may weigh 45-55 pounds. A 50hp outboard will weigh about 200 pounds. <br /><br />So a 16 foot fiberglass skiff with a 50 horse outboard will need about six cubic feet of foam to keep it afloat. A 12 foot plastic kayak will only need one cubic foot. A 30 foot fiberglass sailing sloop with a diesel engine and lead keel would need about 150 cubic feet of foam. Actually, very few 30 foot keelboats have positive foam flotation, but it's not out of the question- especially when you consider all of the air pockets that would exist, as well as all of the wood interior components that provide some positive flotation.<br /><br />Q. Do I need to paint or fiberglass over the foam?<br />A. You can, but it's generally not necessary. Urethane foam will absorb a small amount of water, because some of the the cells are open (90%+ are closed, though). Painting or glassing will seal the foam and prevent any water absorption, but it really shouldn't be necessary unless the foam is constantly immersed in water, such as in a boat with bilges that are always wet. The foam is not UV resistant, so it should be painted if exposed to sunlight.<br /><br />Q. Is the urethane foam resistant to fuel, oil, and solvents?<br /><br />A. Mostly yes- It is resistant to gasoline and diesel fuel, although it will absorb a small amount because no pourable foam can be guaranteed to be 100% closed cell. A strong solvent such as acetone or toluene would eventually break the foam down, but it would take a long time."
