I would like to try building a peened together plane or two and have been told that CuZn37 is the type of brass I need for the sides as it will not work harden like other types of brass. Anyone know what this brass is; McMaster Carr is my regular supplier and they don't list any brass using this nomenclature. Better yet does anyone know what brass I should be using? I know naval brass will work but it is very expensive for a first or so experiment of peened planes.