605. The general rule for finding the proper rivet diameter is Three times the thikness of the materials to be joined Two times the rivet length. Three times the thikness of the tickest sheet. 606. What is indicated by a black 'smoky' residue streaming back from some of the rivets on an aircraft? The rivets were excessively work hardened during installation. Exfoliation corrosion is ocurring inside the structure. Fretting corrosion is ocurring between the rivest and the skin. 607. Which part of the 2017-T36 aluminum alloy designation indicates the primary alloying agent used in its manufacture? 2 17 20.
