So I finally settled for sticking to G20 to use my probe,( thanks step. )
I went on cutting a piece of alum using carbide 1/2 2 FL end mill, 4000 rpm, .118 depth and .15 step over. Feed was 22 and after three turns I found the tool has gone nearly half inch deep. I had to reset and then used a 3/8 4 fl hss end mill fed at 15 doing the same roughing mad it worked fine.
The z axis sloping down - was it caused by the pulling force from the tool? I used the number from g wizard and wasn't even being aggressive. Anyone had similar experience?