I copied this off the site. I removed some items not applicable to the conversation.
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TECHNICAL SPECIFICATIONS
Product:
AlumiFoam Color: Brown
Mix Ratio: 1:1 by weight or volume
Pot Life: 45 seconds
Rise Time: 75-90 seconds
Demold Time (100 gram mass): 10-15 minutes
3-5x expansion
Flex Modulus (psi): 50-1200 flex strength
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The pictures of the bottles match; I kind of figured you were using a different foam, like the 320 or 610.
One thing that did not seem right is that your foams seem different color(s) compared to what mine come out as, a brown or dark tan. I see the specs say it is a brown also.
The ones I mold will not flex, just like it suggest when it says it takes 50 to 1200 psi. In fact, when the stuff first came out I did a mold and took the lure and hammered it, yes, with a hammer, and it did almost no damage. I had a video on YouTube a long time ago but my wife took my channel down. I then took the same lure and tied it to about 5 feet of line, and the end of a fishing rod, and repeatedly smashed it into my concrete patio. It took several smashes to break it. This lure blank did not even have a wire frame in it.
Recently I made some floating jig heads, without hooks, for a friend so he could cut a grove, insert his hook, and glue it in. He could not get his saw to cut it (I use a Dremel cutoff wheel).
So......... what is the difference? I am not sure, but I have to believe it is one of a very few things.
1) The bottles are not properly mixed. Sometimes shaking it is NOT enough. I have used a bent wire on a drill to mix it. Don't worry about bubbles, you will make more.
2) User error, not mixing correctly. Follow the directions exactly, and if necessary, have a friend come over and do it and watch them to see if it comes out different. Do not instruct them, have them do it on their own.
3) Last option, and until the first two have been completely verified by competent and experienced people I won't accept it; you might have got bad bottle(s).