In article ,
"Lloyd E. Sponenburgh" lloydspinsidemindspring.com wrote:

Joseph Gwinn fired this volley in news:joegwinn-
:

What
problems were they solving?


Pretty simple. The fact that they were roll pins somewhat suggests they
were NOT designed to be removed.

Certainly. But my theory was that the original design had a pin through
the shaft so the pin could engage both slots in the washer. Although my
guess is that the pin was loose, trapped by the washer, it could have
been a roll pin pushed all the way through as well.


So, they were simply enforcing that the face of the friction washer would
be the ultimate yield point if something slipped, rather than having the
washer slip on the shoulder of the shaft.

That makes sense. Prevents damage to the shoulder and washer.


Although my grinders have a mere shoulder, _I_ would rather have them
slip on the paper washer than to slip on the shaft -- if they ever
slipped; which they have not.

Given that both pins were partly sheared, it was certainly trying to
slip.

Joe Gwinn