I would guess "fang of the forge" refers to some sort of blade, most likely a dagger or short sword. Swords have often been called the "tooth and claw of man" because we lack the natural weaponry of other preditory animals. The sword is an artificial fang crafted in a forge.
Wall at Arms Length is obviously a shield, most likely a Tower Shield, which are often refered to as "walls". The name seems to describe the fact that the shield or "wall" is attached to your arm.
Pretty simple eh?
-420
