Evidently, the auger is not creating enough back-pressure to force the material through your nozzle. That's probably due to a combination of factors. First off, the foam material itself is light and compressible. Once the auger threads are loaded with the stuff, it just sits there - there's no reason for more of it to enter the threads, the pile of it just floats on top. Second, your auger stops short of the nozzle; instead of the material being forced through it, it enters a chamber where it can just sit there like a traffic jam. It might be that an auger feed just won't work with this sort of material. Have you considered a piston instead? If you need a continuous flow of melted foam, perhaps a dual-piston assembly would work, with two barrels terminating in a single heated chamber with a nozzle. When one barrel is filled, the piston starts compressing the load and the hopper fills a second barrel. When the first piston is at the end of its stroke, it withdraws and the second piston starts compressing the load in the second barrel, etc.