Is aerosol PU foam closed-cell?

[Crossy]

My floating chlorine dispenser has decided to do a passable impression of a submarine.

 

I've emptied the water out of it but in only manages a couple of days before it needs rescuing with the debris net.

 

So, I thought of filling the air chamber with aerosol foam, but it would have to be closed-cell or it will just soak up any water that gets in.

 

Of course the package label is of zero assistance.

 

Anyone got the knowledge?

 

[Lacessit]

Open cell foams AFAIK are normally part of manufacturing processes. Long time since I worked in that field.

Spray out a small quantity, and let it cure. Then try to compress it. If it flexes fairly fully, it's open cell. If it resists compression, it's closed cell.

[Bandersnatch]

Hi Crossy,

 

This is the PU foam I used on my Thai build, which is waterproof and sets hard

 

Edited March 13, 2020 by Bandersnatch

[bankruatsteve]

My big idea a few years ago was to use it for plugging up places birds like to go to build a nest.  Ha ha say the birds.  They peck it out and back to building.

[sometimewoodworker]

12 minutes ago, bankruatsteve said:

My big idea a few years ago was to use it for plugging up places birds like to go to build a nest.  Ha ha say the birds.  They peck it out and back to building.

I know exactly what you mean. We have just had to block off the access holes they made with concrete board, then the clever buggers Moved up, when those got closed they started going after the smaller spaces so we used stainless steel mesh balled up and stuffed into the holes. AFIK we have won the war.

 

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