Use the Workplane limits page to specify what portion of the model is machined and controls the direction of the slices. By default, the whole model is machined. Workplane limits are useful when:
- The pattern extends beyond the end of the port.
- The orientation of the port does not match the plane normal to the pattern. Port machining only machines closed slices.
- You only want to machine part of the port.
This page contains the following:
Workplane limits — Select to limit the toolpath to the specified workplanes. If you use workplane limits then the plane of the slices is interpolated between the XY planes of the two workplanes.
Upper limit — Select a workplane to define the upper machining limit 
.
Lower limit — Select a workplane to define the lower machining limit 
.
Note: The limits are at the tool centre (sphere centre) not the tool tip position.