Someone on cc had a great idea to make number toppers out of foam core and then cover them with fondant. My question is: what do you affix the fondant to the foam core with? Is it water or gum glue? Something else? Thanks in advance!

Both of your ideas should work, or you could use a little corn syrup brushed on your foam core.

Thanks so much! I really appreciate getting an answer.

Even shortening will work.

Rae

Thanks Rae!

Missed that part. Great info! thank you AKS

On this Airplane cake http://cakecentral.com/gallery/1826406, the wings and tail are all fondant covered foam core board.

The first thing I did was score the foam core with an exacto knife and then I roughed it up a little with some sandpaper (so the buttercream had something to "grip" to, kwim? ). I trimmed all the edges (don't want any rips!!!) and wiped all the pieces of foam core down with a damp cloth. I then laid them out to air dry for a bit while I worked on something else.

When I was sure that they weren't the least bit damp, I "crumb coated" (lol) them with buttercream and then covered them with fondant and attached them to the plane. The top tail piece, that is, which is most like what you are doing anyway... I think I 1/2 covered the wing, THEN attached and then finished the fondant underneath (what a pain THAT was! OY!).