P.Kepler Wrote:
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> I also understand that Willamette, in the course
> of repairing shays for customers, noted failure
> trends in the shay and made design changes in
> their locomotive to prevent the failures.

This is accepted to be true...one other thing that Willamette design engineers did was
to incline the truck springs in toward the bolster in an attempt to cut down on the
locomotive swaying on poor track.
I had thought this to be a feature on all Willamettes built, but when showing my son
the Willamette in Missoula, Mt that formerly worked for Anaconda Copper, I noticed that
the front truck did not have this feature. I don't have an answer for this except perhaps
it was because this particular locomotive was one of the first ones produced.
Technically speaking, there were 3 models of Willamette:
50 ton 2 truck
70 ton 3 truck
75 ton 3 truck

There were only a pair of the 50 tonners and neither survived. Interesting, they were
a near clone of the 50-2 Shay, but had a 1" longer stroke, making them 11" by 13".
The 70 tonners were subdivided by saturated and Superheated boilers.
The 75 tonners were different both because of the overall weight and having 1/2" bigger
cylinder bores, giving them just a little more t.e. A real shame that they came on so late
as I feel that they would have brought out some really substantial machines to compete with
the bigger Shays.