Dale Cherne Wrote:
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> I had wondered if it was something like that. Very
> interesting. I imagine it will be a very strong
> locomotive once the 3rd truck has a drive again,
> as the engine has a superheater as well.
>
> Thank you very much for the info Tom :-)

For Jeff, I agree with your sentiments. This is nitpicking, but 91 is NOT a
copy of the 91 that operated in and around Mineral into the mid 50's. Yes, they were
both West Coast Special models and basically had the same specs, but the real 91, the
one that was scrapped and the one that 102 was once lettered and numbered for, had
outside admission piston valves, while the current one, whether you call her 102 or 91,
has inside admission piston valves, the desired version.

For Dale, I had the opportunity to ride 91 back in 1986 when Harold Borovek offered me
to ride with him from Elbe to Mineral Lake and back. He & Jack Anderson took really
good care of her then and she was a 3 truck machine running @ 200 lbs. pressure.
Heisler rated this model somewhere around 43,000 lbs. t.e. @ 75% boiler pressure. Using
85% like a lot of builders did, it was up to around 49,000 lbs. and that is really robust.
I don't have them them in front of me right now, but I did the numbers once and a West Coast
Special Heisler like 91 has more cylinder volume with it's 2 cylinders than a 90-3 class
Shay does with its 3 cylinders. A 90-3 class Shay was the largest selling off the shelf
class of Shay and they were real pullers. 91, when all together as a 3T machine was a
pretty impressive locomotive and got down the track about as fast as a 44" drivered
rod engine. I had a little experience both running and firing her in 2005 and didn't
like her at all. The cab is very poorly laid out with the independent and automatic
brake valves several feet apart. You have to stand most of the time while running her
and really wrestle with the throttle as the packing is so darned tight that it takes two
hands to regulate it. Just my opinion,. but I have had a fair amount of time on 2 other
3T Heislers, one for pay for a whole summer and that on 8.6% grades. Although this one
was pretty worn out, she steamed easily, held the rail well and was comfortable to spend
hours on. It was former Pickering Lbr. Corp. 10.
BTW, all things being equal, just adding a Superheater does not neccesarily make an
engine more powerful. It is an economy device that raises the temperature of steam
up to 300 degrees or so, giving it more bang for the buck as it were. Hotter, drier
Superheated steam has more volume and accomplishes more work.
Saturated steam @ 200 lbs. is 388 degrees F. With clean tubes and hard work creating
a strong draft, this temp can be raised via the Superheater up to around 700 degrees F.
I have personally experienced this while firing Grand Canyon Ry. 4960.