[Shop-talk] Blackening sockets/wrenches stamped markings.

[John Miller]

> For some years Detroit, in particular, chose their metric fastener head
> sizes to be close enough to let you use SAE wrenches - and while we all
> know to grab an 8mm for a 5/16 head and vice-versa, 1/2in fits most
> 13mm, 5/8 usually fits 16mm, 19mm and 3/4 are interchangeable as are 7/8
> and 22mm, the true Detroit oddity of the '80s was the M6 fastener with
> the 11mm head sized to fit a 7/16 wrench.

9/16 is usually too tight on a 14mm head but you will, at times, find 
14mm fastener heads that were obviously sized to fit a 9/16 wrench, too.

John.