Does poly melt Great stuff foam?

[NSBCraig]

I know it's been discussed but I'm not finding it.

Does poly melt great stuff minimal expanding foam?

 

[Intermediate Mariner]

Re: Does poly melt Great stuff foam?

hey NSB,

Everyone says it does and bet theyre right.

What you want to buy is URETHANE foam... the poly won't melt this. It is available in liquid but not sheets that I could find.

ALSO epoxy resin will not melt most foams.

 

[NSBCraig]

Re: Does poly melt Great stuff foam?

Yeah that's what I was thinking.

I just wanted to fill some space with it.

Thanks.

 

[Mark42]

Re: Does poly melt Great stuff foam?

I know it's been discussed but I'm not finding it.

Does poly melt great stuff minimal expanding foam?

Yes, for real, it does.

The blue foam in the home centers sold in sheets will not melt from poly resin. But its a sheet, not a spray. Its called polyisocyanurate foam.

 

[109jb]

Re: Does poly melt Great stuff foam?

I beg to differ. I have used Great Stuff numerous times for filling small gaps and even making temporary molds for projects later covered with polyester resin with no melting of the foam. Now I will say that I don't know if there is a difference in the regular Great Stufff and the minimal expanding variety, but the regular stuff handles polyester resin fine in my experience.

Also, not all blue foams are the same. Dow makes a blue insulation board that is polystyrene foam. Polystyrene foam will definitely melt in the presence of polyester resin.

If in doubt, you can always try an experiment and squirt a blob of foam on a scrap of wood or cardboard and let it cure. Then hit it with some resin and see if it melts.

 

[Mark42]

Re: Does poly melt Great stuff foam?

I beg to differ. I have used Great Stuff numerous times for filling small gaps and even making temporary molds for projects later covered with polyester resin with no melting of the foam. ......

I was messing around with expanding foams when building my hard top about two years ago. I can't recall if the foam I was using was actually the Great Stuff brand. It may have been something else, or one of their other products.

I can say with 100% certanty that the polyisocyanurate foam board is not affected by polyester resin at all. It was one of the products I tested before deciding which foam to use. It was sold by Lowes at the time and was blue with a foil face.

 

[tdrudd87]

Re: Does poly melt Great stuff foam?

It was sold by Lowes at the time and was blue with a foil face.

That's the difference! I think many of us call "blue foam" the stuff that has no foil, but a think layer of cellophane-like plastic on one side. Not sure of the type it is, but it is definatly eaten by poly resin. I'll look for the foil stuff next time I'm there and we can compare trade names.

Terry