What is the most buoyant foam?

[Howler]

If really want lightness fill them with helium..

At that point, consider shaving off your eyebrows. It'll save about as much weight as replacing the air in your buoyancy bags with helium, and it'll cut down on windage too!

 

[claudiajohnston]

In search of buoyant foam to add to a sinkable dingy so it doesn't sink.
I suppose it must be PVC, core cell, divinicell, etc. ? Know a source for these foams?
What about that 'blue stuff'? used in docks, that seems cheap and plentiful but is it 'floaty' enough?
Holds up a fricken heavy dock..so..
The plan is to take a sailing dingy, a Dyer Dhow to be exact, which when fulled rigged and capsized, will sink..( ask me how I know !) and make it self rescuing....reverse engineering.
Just about the stupidest thing is to have a sailing dingy which is NOT self-rescuing.
I did locate a factory in NJ that is said to build the most buoyant foam ever, mostly sells to military contractors: ie. General Dynamics ( they make submarines) and the cost is incredibly high. I don't have Pentagon budget. Maybe the damn subs would be cheaper if they could get cheaper foam which worked well. That is the foam I am looking for atlanta ceramic coating and ppf.

As those of you who have seen my Arrowbolt thread will know, I'm currently removing the floor (compost), stringers, waterlogged foam etc.

When I refit with new in the coming weeks, I want to replace the buoyancy foam that is in pockets in the bow, under the floor and in stern side pockets etc. However, I'd like to think these foam materials have progressed a bit since the boat was built (70's/80's). Are there any water resistant equivalents that don't act like a giant sponge? Perhaps I could fill with ping-pong balls or similar - or would they rot?

Is there any reason I shouldn't use the aerosol expanding foam as found in builders merchants? Is there anything else anyone can recommend?

I know I could leave the voids empty, but kinda like the idea that where there's foam or something else, the water wouldn't be able to swamp quite so quickly in the event of a hull breach etc. (Ok, ok, so I'm paranoid... )

Thanks as always.

 

[Zonker]

The 2 part expanding foams are reasonably water resistant.

The aerosol spray foam will absorb water I think.

 

[mckenzie.keith]

Collect recyclable plastic bottles from the trash. Put them in plastic or mesh bags and stow them securely in your dinghy.

As those of you who have seen my Arrowbolt thread will know, I'm currently removing the floor (compost), stringers, waterlogged foam etc.

When I refit with new in the coming weeks, I want to replace the buoyancy foam that is in pockets in the bow, under the floor and in stern side pockets etc. However, I'd like to think these foam materials have progressed a bit since the boat was built (70's/80's). Are there any water resistant equivalents that don't act like a giant sponge? Perhaps I could fill with ping-pong balls or similar - or would they rot?

Is there any reason I shouldn't use the aerosol expanding foam as found in builders merchants? Is there anything else anyone can recommend?

I know I could leave the voids empty, but kinda like the idea that where there's foam or something else, the water wouldn't be able to swamp quite so quickly in the event of a hull breach etc. (Ok, ok, so I'm paranoid... )

Thanks as always.

I think I would buy some kind of expanding flotation foam from some kind of marine supply place. I am not sure if the expanding foam from builders merchants is totally closed cell foam.

I think pingpong balls are made of cellulose. Probably a bad idea.

If you want to do something quick and dirty, shove empty but capped water bottles everywhere there is any void space. You can collect them from the trash or recycling bins. Probably a terrible idea. But maybe a tiny bit better than pingpong balls.

 

[claudiajohnston]

Collect recyclable plastic bottles from the trash. Put them in plastic or mesh bags and stow them securely in your dinghy.

I think I would buy some kind of expanding flotation foam from some kind of marine supply place. I am not sure if the expanding foam from builders merchants is totally closed cell foam.

I think pingpong balls are made of cellulose. Probably a bad idea.

If you want to do something quick and dirty, shove empty but capped water bottles everywhere there is any void space. You can collect them from the trash or recycling bins. Probably a terrible idea. But maybe a tiny bit better than pingpong balls. charlotte concrete coatings

thank you so much for your suggestion