We have success, Using the settings from routercnc I was able to cut aluminium without breaking the end mill or blunting the end mill. Now just to fine tune, I used a zig zag plunge from zero Z axis height and it was too slow I think at the low plunge depth I will try it without the zig zag or increase the plunge rate and keep the zig zag, Now all I have got to do is the same for a 6mm end mill. Thanks again routercnc.