2 Lb Density Expanding Pour Foam, 2 Part Polyurethane Closed Cell Liquid Foam for Boat and Dock Flotation, Soundproofing, Filling Voids, and Insulation (Quart Kit)

I used it on a lifeguard float I use to display a dive flag that I had cracked and wanted to salvage. I did the math on volume of the interior in like 5 seconds and was off on my mix a little on the too much side. Was quite enjoyable when the reaction happened as it was quite explosive. I had just poured one part in then the other and shook the entire float. This is contrary entirely to the instructions mind you, but it apparently works well enough and maybe a minute later the float was launching foam from the cracks and the plug hole. 10/10 entertainment value alone.

0.5 ounces and this is expansion rate. Wonderful stuff

I teach Sunday School and do quick science experiments to keep them interested and wanting to come to class. Polymerization is an amazing thing. I mix the chemicals in a small plastic cup and it overflows the cup. After it dries, I pass it around. Kids like to take it home. I do wipe off the lids with paint thinner so they will re-open next time. the lids can seal shut.

It works well but it requires labelling. I found out that the dark stuff is the Isocyanate and the light stuff is the Polyol. And if you want to use a scale to measure by weight, the mix ratio is 100:88, Isocyanate:Polyol. The Isocyanate weighs more than the Polyol.Be sure to mix it with a drill so that you have maximum time to work with it before it starts foaming. It starts to foam about 40ish seconds after you start mixing (in an air temp of 65 degrees F) so you don't really have a lot of time to get it where you want it. Not a problem if you are pouring it, but if you are painting it on something you have to mix it in small batches to account for this. It seems like it takes about 20 minutes to fully expand and dry.If mixed in the proper ratio, the final product is very brittle and rigid, and somewhat fragile. If you add more Polyol, you can make it a bit more flexible and way more durable. I have mixed it up to a ratio of 100:130 by weight (Iso:Poly) and it still expands and dries more or less the same; meaning final product is not sticky and uncured and still takes the same amount of time to dry and expand. For me the best ratio to make it pretty flexible and extremely durable was 100:110 Iso:poly. Yes this means you will have some Iso left over but thats just a small consequence for hacking the system.

This stuff failed miserably for my application. It expands very quickly if you have any thoughts of using a funnel of any kind just forget it! despite my failings with it the foam itself is very strong and dose what it says just work fast and forget funnels! i made a simple funnel out of a sheet of cardboard to try and pour it into a hard to reach spot and it just foamed up in the funnel blocking it almost instantly.

Does not work where there is any water

I have used this product for several projects over the years, from filling a hole left in a basement wall where the conduit from a service entrance that was moved came thru (it takes several as it has to fill the void in the block from the bottom of the wall up past the hole), to filling false 6x6 posts at the end of my driveway.

Well worth the cost