I recently purchased a gun grade expanding foam from my local decorators' merchant. They had the Soudal foam and the BondIT Megafoam.
My first task was to fill a 8mm wide and 6mm deep channel in a concrete window sill. The replacement sliding sash window had a lot of bounce in it. I decided to lock it in place using a combination of expanding foam and Timbabuild 4 hour epoxy resin.
The epoxy resin worked as well as expected, the expanding foam, less so.
I purchased the BondIT Meagfoam. I misted the area to be filled with water (after vacuuming it). The following day, I ran a knife along the excess foam and pulled it away. I had anticipated that I would need to sand away the excess foam from the timber face of the window sill. Nah, the foam had not stuck to the (water based) paint.
I later tried it on GRP flashing. It didn't "stick" to either the GRP or the brickwork.
To date it is the only expanding foam (which I have used), that, a) doesn't want to stick to anything and b) remains incredibly soft/compressible after curing.
The day after buying it, I went back to the store to purchase the other brand- which worked as expected.
In the end, I used the pants foam to fill the gap under the GRP flashing and behind the GRP upstands and the Soudal to water proof the join (I will use a UV safe MS polymer over the cut back foam once done).
There may well be times that I want an expanding foam that remains incredibly soft, but I would have preferred if BondIT had mentioned that at the point of purchase.
My first task was to fill a 8mm wide and 6mm deep channel in a concrete window sill. The replacement sliding sash window had a lot of bounce in it. I decided to lock it in place using a combination of expanding foam and Timbabuild 4 hour epoxy resin.
The epoxy resin worked as well as expected, the expanding foam, less so.
I purchased the BondIT Meagfoam. I misted the area to be filled with water (after vacuuming it). The following day, I ran a knife along the excess foam and pulled it away. I had anticipated that I would need to sand away the excess foam from the timber face of the window sill. Nah, the foam had not stuck to the (water based) paint.
I later tried it on GRP flashing. It didn't "stick" to either the GRP or the brickwork.
To date it is the only expanding foam (which I have used), that, a) doesn't want to stick to anything and b) remains incredibly soft/compressible after curing.
The day after buying it, I went back to the store to purchase the other brand- which worked as expected.
In the end, I used the pants foam to fill the gap under the GRP flashing and behind the GRP upstands and the Soudal to water proof the join (I will use a UV safe MS polymer over the cut back foam once done).
There may well be times that I want an expanding foam that remains incredibly soft, but I would have preferred if BondIT had mentioned that at the point of purchase.
