Check the edges of all the surfaces you hammer on. Are they straight? The standard square bench block will work for most of your projects but sometimes a longer one is desired for things like bracelets. Check your local machine shop. They may have scraps they can cut and polish a bit for you. Are the edges curved, and if so, how much? Thanks to Kim St. Jean, I now use one of my old sad iron bases as a bench block. Tighter curves can be achieved with a small round bench block, and points can be made with an anvil.