What adhesive are you using to build your foamies? I used 5-minute epoxy for a long time, then a friend said he heard people were using hot-melt glue. You know, the kind used for "craft" stuff. Well, I had a hard time believing it, I just couldn't imagine it being strong enough. I happened to already have a dual-temperature glue gun, so I ran some experiments on test pieces of EPS foam. Seemed to work, the bond was stronger than the foam itself.
So then I decided to try building an entire plane using only hot glue. This was So.14, my 91st RC plane, built in December 2002. Needless to say, the hot glue held, and I was quickly converted, especially since I think any kind of waiting is terribly inefficient, and that includes waiting for glue to dry.
Here's some tips for using hot glue:
Hot glue works well on EPS and EPP foams. When used on fan fold foam (Dow Blucor), I've discovered it fails over time.
I use MultiTemp glue sticks from Adhesive Tech. You can get a bag of 50 sticks at Walmart or other stores for as little as $2. Fifty sticks last a really long time. Do you know of a less expensive effective adhesive?