Molly Brown wrote:
Why is the hole of a ¼” fender washer ¼” but the hole of a ¼” cut
washer larger than 5/16”?.

Um, lessee- what is a plausible made-up answer for this? Fender washer
(as the name implies) is so the bolt won't draw through the substrate,
so you want a tight fit, where the bolt can't pull through the washer.
Regular washers, you want them to be able to move around a little so as
to act like a little bit of a bearing when things flex? They can also
deform a little when tightened, to seat better.

IOW, hell I dunno. But now you have me curious. Where are our resident
Actual Engineers? I've only used fender washers with self-tapping bolts
and machine screws, not through bolts with nuts. (And it was usually on
actual fenders and other car body parts, to refasten through
wallowed-out holes in sheet metal.) I guess the washers for carriage
bolts fall somewhere in the middle- I remember them as being a pretty
tight fit, but they are smaller than fender washers.

--
aem sends...