RE: Firewall Laminating
I prefer to use aliphatic resin (like Titebond wood glue) for laminations. Spread it evenly across the surface and clamp the surface together with even pressure (a stack of heavy books works well). The glue will soak into the wood, but the excess glue will tend to squeeze out evenly and leave the two surfaces perfectly mated together. Once fully dry, the wood will fail long before the glue line ever does. Just make sure your surfaces are clean, reasonably smooth, and free of any loose fibers before mating.
Thicker glues like epoxy, which work great when you need to fill a void, will work against you in a lamination, since the glue has more body that can prevent the surfaces from lying flat against each other (creating the potential for uneven thickness), and it really will not add any significant strength to the lamination.
The biggest downside to aliphatic resin is that it is not waterproof, so if you are building pontoons (or a boat) be sure to seal the lamination well.