Hi Colin, The contractor told me they have large quantity of legal MasterCAM liscences (about 15 seats). They told me they will ask their reseller for help. The responses are slowly. I have to accept "break many" for prototype even if it may not the best method. Thanks.

Machining contractor use break many to convert spline to arc. The result is no so good. A correct direction/method is needed for machining vendor. I have asked contractor to contact his MasterCAM reseller for help but no feedback.

The requirement is profile error 1um (an GT&T tolerance). It is the same as MasterCAM chord error 0.5um.

How to generate 2D cam contour toolpath with high accuracy with MasterCAM/How to fab precision CAM with MasterCAM? Accuracy requirement: tool path profile error within 1um, or chord error within 0.5um. My machining vendor convert 2D cam cotour to arc with chord error setting to 0.5um but actual maximum chord error is 3.7um. CAM contour is comprise of convex and concave profiles. The converted arc is comprise convex arcs and linear lines only. There are no concave arc. The maximum chord error is near center of concave profile. The chord error of most converted arcs are less than 0.25um. This generate unnecessary high number of arcs. The total number of arcs/lines is about 350 per cam profile. Thanks