are you going to forge a rounding hammer, cross peen? what size? then we can start talking seriously! tools you will need for any hammer is: anvil, forge, big hammer/small hammer(or a power hammer), hammer eye punch(I recommend B. Brazeal's), drift. if you want to forge a rounding hammer you will need: cupping tool, top/bottom fullers, flatter, camel hump tools, + the rest. there are may good videos on you tube on forging hammer.(I probably seen most of them). P.S. 2" semi axle works good for hammers about 2 1/2 to 3 1/2 lbs. (its 4140 I believe...)