"Stupendous Man" wrote:
This brings to mind a question I have had for a long time.
Our local supply store (USA) carries Grade 8 (gold), Grade 5 (gray),
and the common (standard-silver) bolts. My question is what grade are
the common bolts? Or dont they grade them?

Unmarked bolts are usually grade 3, or worse.

I made the mistake of buying a bunch of the 1/4" bolts out of the bulk bin
at Home Despot a few years ago. They came apart tightening them with a 1/4"
ratchet drive, and looked like pot metal on the inside.

I don't look to HD for fastners anymore.

Jon