Anyone use this type of material in the past? 

I've used it once, expanded 16 times in volume if I'm correct... the foam had a nice "skin" against the mouldsurface and was porous on the inside...like it should be

Today i tried to make a plug with this material. I went for the Foam-IT 5 (10X expansion).

I'm not sure if the low temperature in the shop (15ºC) or incorrect mixing time will bring me problems.
The foam has a lot of soft spots an i'm finding very hard to demould.  The mould was waxed and with 4 coat of easelease.

Matthieu, in what kind of mould did you use the foam? Silicone? Epoxy? Polyester?



 

As far as I know you need another release agent... I've used APW instead of a "normal" composites release agent...

demold was difficult for me too. I also used a semiperm for release on an epoxy mold. the surface against the mold was softer and the cells crushed very easily, not anywhere as rigid as the surface open to the air. 

Out of interest, would this (or rather, the stuff you can get from hardware stores, eg. https://www.masters.com.au/product/902404820/fuller-fula-foam-fire-resistant-500g) be suitable for similar methods to that used in the EC pattern making tutorial? Ie. closed cell foam core (probably Corecell SAN foam) spine, then use expanding polyurethane foam instead of the PU foam blocks that EC uses? I know it would be a lower density, but would that be a huge issue? Would it still work fine with filler, etc?

It could surely work! make a skeleton out of wood for example, fill the gaps with PU-foam from spraycans from a DIY store an then sand.

Unfortunately someone else will have to find out, I picked up some pourable 2-part PU foam this morning instead. $35 for 2kg, makes it cheaper than the stuff from hardware stores, if not a little harder to use. Will just pour it into ice cream containers to make my own blocks, gives me a much better density for patterns.

Post pics if you can I would be very interested in following.