Q. How good is the machinability of cast copper alloys?

Machining data for copper casting alloys are similar to those of their wrought counterparts. The most easily machinable are classified as Group 1 and include CC491K (LG2) with a rating of 90% (this rating is based on a 100% value for free machining brass CW609N, CZ121). The more difficult alloys to machine are classified as Group 3 and include the aluminium bronzes such as CC333G (AB2) with a rating of 20%