I
found some very interesting information in “Drills and Mills”, second edition, book
by Will Meyerriecks. There was information from the Homestake Mine stamp mill
components life expectancy. It listed all of the major wear components in stamp
mills in Leads, South Dakota. The information was taken from files
that were kept on the mine site.
The table below shows the major components, material they were made
from, weight and life in months. I was amazed to see that the stems were only
good for about 4 months, only two other items have a shorter life and they are
the dies and shoes. You would expect them to have the shortest life expectancy.
If you add up the weights for the tappet, stem, boss and shoe you come
to 898 pounds. They were smaller than the standard stamp of 1,000 pounds. The
boss on a 1,000 pound stamp mill would weigh more to make up for the
weight difference. Most of the mills have a standard stem of approximately 14'
long and 3 1/8" to 3 1/4" diameter. I'm sure that there were many
odd-balls. The picture below shows that stamp mill at the Homestake mill.
