I'm running a part on Sunday, main datum is a half external sphere. It measures 5.5mm diam using least squares BF, in tolerance, all is good. All vector pts, lots of them prob 40-50, constructed sphere. I mic it for fun in varying angles and get 5.51mm. Totally acceptable diff being lst sq vs Mic and all the other errors floating around.
So I decide to run it at minimum circumscribed....should be larger than lst sq, no? Welp....i get 5.48mm. How could min cir be less than a lst sq? I'm baffled.
