What Is A Fender Washer?

The term Fender washer applied to a particular category of washers which would characteristically have a greater outside diameter vis-à-vis the inside diameter.

In general a washer is the term used to describe a thin plate (characteristically disk-shaped) which has a hole (characteristically right in the middle), typically used so as to share out the load of what is known as a threaded fastener.

Some of the other possible uses of a washer would include as a spacer, as a wear pad, possibly a spring, maybe a preload indicating device, as well as a locking device. All washers will typically have OD (that is, outer diameter) roughly double their ID (that is, inside diameter).

My understanding of 'fender washer' is: A large flat washer, used to repair fenders on automobiles which had large exposed fenders... Especially those from the 1930's. I had a 1934 Chevrolet, back in the '60's, and both front fenders had cracked from road rattle at the top edge of the wheel well. The easy repair was a couple of 'fender washers' and a steel plate on the inside held together with a couple of stove bolts. A better, but more costly, repair involved welding the crack while applying a metal bar to the inside of the fender for support.