"Capt. Rob" wrote:

No, you provided a load of malarkey; please try to explain how you
can
produce shear forces on one or two, or three bolts in a coupler but
not
on the remainder. It can't be done

Bwahahahahahahaha!!! Right, Martin.....all of the loads and breakaway
points are identical, right? So when this type of gear fails ALL of
the bolts shear away in the same instant!

If you rotate one flange against the other sufficiently far enough to
shear one bolt, you're going to shear them all, it's really pretty
simple. Besides I don't believe the weak point here is the bolts, they
represent a far greater tensile strength than the woodruff key, or keys
depending on your drive arrangement.

Cheers
Marty