On 19 Sep 2005 22:07:37 -0700, "Bryan" wrote:

Whilst thinking about another problem, I find myself wondering, "why is
it that bolts have hex heads rather than octagonal or some other
number?"

Is there some wisdom about the history of this?

bmw

A guess: bolt heads were once square, requiring 90 degrees of
rotation before a simple wrench could be repositioned to grab another
bite. Machinery got more complex, spaces got tighter and access more
limited, hence hex requiring only 60 degrees of rotation between
bites before robust ratchet wrenches were available.

It's easier to strip the corners off a hex than a square, but the hex
is usually strong enough to shear a bolt before the corners fail.