ISO 14405-3:2016

ISO 14405-3:2016 establishes the default specification operator for angular size and defines a number of special specification operators for features of angular size: cone (truncated, i.e. frustum, or not), wedge (truncated or not), two opposite straight lines (intersection of a wedge/truncated wedge and a plane perpendicular to the intersection straight line of the two planes of the wedge/truncated wedge, intersection of a cone/frustum and a plane containing the axis of revolution of the cone/frustum). See Figure 1 and Figure 2.
ISO 14405-3:2016 also defines the specification modifiers and the drawing indications for these angular sizes.
ISO 14405-3:2016 covers the following angular sizes:
-      local angular size:

-      angular size between two lines;
-      portion angular size;

-      global angular size:

-      direct global angular size:

-      least squares angular size;
-      minimax angular size;
-      rank order angular size/indirect global angular size:
-      maximum angular size;
-      minimum angular size;
-      average angular size;
-      range of angular sizes;
-      mid-range angular size;
-      median angular size;
-      standard deviation of angular size.


ISO 14405-3:2016 defines the meaning of tolerances of angular sizes indicated as
-      + and/or - limit deviations, e.g. 0�/-0,5�, or
-      indicated with upper limit of size (ULS) and/or lower limit of size (LLS), e.g. 35� max. or 15� min., 34�/36�,
-      with or without modifiers.
ISO 14405-3:2016 provides a set of tools to express several types of angular size characteristics. It does not give any information on the relationship between a function or a use and an angular size characteristic.