Great Stuff

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Well-Known Member
May 25, 2004
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I have been reading up some on foaming the fin can. I have a can of Great Stuff at home but not sure if I should use it or get a slower foaming foam. The great stuff puffs up so fast. Im scared that even if I leave the bottom centering ring off it will still puff up to fast and hurt the BT. Has anyone used it and how well or bad did it work.

I've only had one experence with Great Stuff in the spray can, I wanted to fill a Bt-80 nosecone.. I didn't realize once you push the button that's it for the WHOLE CAN :D:D I had the stuff All over the basement, out the basement door and all over the yard! OH man what a mess:D:D but that cone was really packed tight;) I've stopped trying to use spary can expanding foams.
Wish I had a photo...I was covered , the dog got some as did the outside work bench...

You don't want to use Great Stuff for foaming rockets. Mainly it is because it requires exterior heat and moisture to cure. When you think about it, what would happen if your rocket was going to land in a puddle or you were to fly in extreme temps? That Great Stuff would heat up or get wet and start foaming again in that enclosed space. NOT a good thing! :p

I recommend going and buying some of PML's two-part expanding foam or going to your local RC boats and/or planes shop and getting some of the NHP or similar TWO-PART thought the Great Stuff expanded fast...HAH! Once you mix's fully cured in about 4 minutes! :eek:

Make sure you get used to it before you do anything else by mixing small batches and experimenting with the expansion rate.

I forgot to attach this picture. This is of from when I foamed the fin con of my 29mm Big Daddy. It was all over the place!

I was pretty easy to cut and Dremel down to fit, though.

Originally posted by jetra2
This is of from when I foamed the fin con of my 29mm Big Daddy. It was all over the place!

Is that an optical illusion, or did the foam actually distort the BT?