I don't use the foam as a structural component, it just helps silence the clunk.. The arrows are sealed(use shaft cutoffs from the local archery center) and embedded in an epoxy matrix. They provide a very stiff and light weight component to tiffen the stock. I don't know if the foam will stand up to AcraGlass. It may disolve! One could try it but the foam wouldn't be nearly as rigid as the arrow shafts..