scope:

This specification defines the inspection criteria and requirements in inches for gaging the head protrusion values for 100º flush head rivets and threaded fasteners;

Type A - Rivets (i.e. NAS525).

Type B - Externally threaded 100º Full Flush Head fasteners (i.e. NAS1580).

Type C - Externally threaded 100º Reduced Flush Head fasteners (i.e. NAS1581).

This specification includes the individual flush head protrusion gage block diameters, the method for determining applicable individual gage block diameters and acceptable gage diameter wear factors.

Recommendations for improvement and/or corrections to this standard practice document should be directed to an NASC Representative or to the National Aerospace Standards Committee

Specifications herein, of issue in effect on date of price inquiry, are a part of this specification to the extent indicated. In the case of conflict, the requirements herein shall take precedence.

This Standard Practice takes precedence over documents referenced herein.