Group of workers working on riveting an M3 tank. Thousands of rivets are used in the production of one of the huge thirty-eight ton M-3 tanks. Whenever possible rivets are replaced by welded sections, but throughout much of the tank, as in the side plates on which this riveter is working, the steel plate is too heavy for welding. . Image from File:M3 tank riveting LOC fsa 8e10699.jpg in public domain.