Thread: Adding floatation

I need some help on a project. I have an old V bottom boat with 3 air chambers for floatation. I am wanting to know if anyone has any experience with using the aerosol cans of foam to add floatation in a boat. I have thought about drilling several holes equi- distant apart along the top edge of the air chamber and 1/2 filling the chamber with 2-3 cans of the aerosol foam used to seal windows and doors. Does anyone have any experience doing this?

Is the top of the air chambers below the water line or above. The cans you are talking about are open cell correct.

I am going to say the air chambers above the water line. Regarding whether the foam is open cell or closed cell I suspect it is open cell. Your thoughts?

Ya I have not seen a closed cell in a can before. I have done a bunch of restores and read a lot foam and this is what I can gather. The closed cell some thinks wont water log which is way wrong. I think people use the two part pour in closed cell form to help the hull be a little more ridged than anything. You could probable say the closed cell is more buoyant than the open when anhydrous. But I think the cans would work just fine especially when you talk cost. I have used those big Hilti cans before on different areas of a boat and they worked fine. I have also heard of people lining the compartments they spray in with visqueen then sealing the top to not allow any moisture to the foam. Alot of the old timers would just use empty pop bottles below the decking to add flotation. I have seen the boat you are using and I would go the way you are thinking. Just take into consideration the water displacement below the water line. Meaning not need to have three inches of foam below and five above.

Beans- My thought was after I filled the chambers with foam then I would have a friend of mine, who is a welder, just heliarc the holes shut. I am going to talk with him before I do it.
I appreciate your thoughts. Thank you

Originally Posted by cricket george

Beans- My thought was after I filled the chambers with foam then I would have a friend of mine, who is a welder, just heliarc the holes shut. I am going to talk with him before I do it.
I appreciate your thoughts. Thank you

That could be exciting. Many aerosol foams are highly flammable. Let me know when to watch for the fireworks show!

All kidding aside, I hope your TIG welder is very good.

DC - I was concerned with that. I talked to my welder this morning and he said he has a boat similar to this one. He took a long 1/8" drill bit and drilled thru the chamber and hit foam. His was also a 1950's era boat. I think I may try that and check for foam too. If I hit foam I'm done. He did say that even with the foam he has sunk his boat at Ft Cobb one winter day when the boat was loaded down with ice.