Dressing hammer faces?

[NDallyn]

I've picked up a couple hammers to start forging with (a 4lb short sledge, and a 32oz. ballpein) and ground the faces flat and square and polished to a mirror finish. Is this the proper way to dress a hammer for forging? How much of a bevel do I want to have around the face?

Nathan

 

[Sam Salvati]

all corners rounded, with a very slight crown. If it is a two sided hammer not a cross/straight/ball pein, then give one side a very slight crown, and the other side a bit more to do the rough work with the high crown and the cleaner smoothing work with the less crown.