GMNA C215 PDF

GENERAL Engagement gaging provides a means for determining the suitability of the external wrenching 6-lobed driving provisions on the heads of threaded fasteners to accept and conform with mating driving tools for the length of engagement considered necessary to develop tensional characters adequate to properly tighten the fasteners. The use of products having too shallow engagements could result in production problems such as reaming of the 6-lobed features or excessive wear on driver sockets.