Nother question, Did you shake the can of great stuff up real well before you used it?

Deadbolt
I bought a can of Dow water base foam that did the same thing. I did everything I could think of and I still had a mess. It never would set up. I cleaned the stuff off the target and bought a can of great stuff and it worked fine. I have used some other generic stuff in a black can from Menards that worked fine also. The methods above like Eric Krewson stated are what I use and have repaired several targets. You may have just got a can of bad foam. I Probably won't buy another can of the Dow foam.

The best foam I had used is from 3-D Country. The target will be as good as new or sometimes even better(more durable)than new. There's lots of infos and a how-to video on their website 3-dcountry.com

Blacky

Shake the can and then shake it some more.  Unlike some of these guys I only tape one side of the target and then let the foam expand freely on the other side.  I let it dry well and then I use a razor knife to shave the excess.  Some times it takes a few days to cure, but it always works well for me.

I don't cover the target with anything I just shoot it in a half a can at a time.  Then when it is done I just trim it back to shape.  I does take a couple days to set up good.

Here you go, Hot Hap found it for me.

http://tradgang.com/noncgi/ultimatebb.php?ubb=get_topic;f=1;t=048562

Gatekeeper Tom says
 "I have a target I shot completely in half and instead of trying to fill the big void area of vitals...."  
HAHAHAHA! Now thats funny right there, I don't care who you are!

Maybe he had some friens over to shoot.......

LOL

Sorry guys dont tell the misses but I'm on a getawat for the weekend and stuck on the wireless card haha

i redid the targets filled em good sealed them and cranked the heat in the barn to 80...took a few days but they cured up nice and tight!

Worked like a charm so the problem was moister and cold...no good!

I tested the smaller one when i gave it to my cousin and he shot it with a compound at 60# at 5 yards and stopped it like nothing!!