Re: 493

Russo Loco Wrote:
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> Thanks for those photos, William -
>
> Just what the doctor ordered!  While a good
> deal of the K-37 design was based on drawings of /
> reverse engineering the K-36's, the frames behind
> the fourth pair of drivers are distinctly
> different.  I wonder to what extent the
> differences between the swing hangers on a K-36
> trailing truck versus the sliding plates on a K-37
> trailing truck accounts for the rumored
> differences in their tracking on sharp curves?

The Hodges truck on the 480's is more flexible, but does not have as much lateral resistance, the 480's tend to "wag their tail" when not pulling hard.

The Cole truck has more lateral rigidity, that makes the rear of the engine ride more stable, but in theory could make the engines more derailment prone, especially in reverse. The K28's don't seem to an issue with backing, but the K37's apparently had somewhat of an issue, although we never had a problem with the 497 with that.

I remember being on a work train with 497. We were sent up to a spot near MP 328 (Apache Canyon Rd Crossing) to put some shoulder ballast on a curve that kept kicking out. We dumped some of the ballast, then had to run down to Los Pinos to clear the afternoon train. Once they got by I had to back 497 up to the kinked curve with the ballast cars coupled to the front end. I eased into the kicked out curve, watching the tender hook hard to the right as it rode the kink. 497's cab - whose back wall is about 7 feet behind the trailer truck axle - kept going straight. I was expecting the big "BANG" when the trailer truck went on the ties, but eventually the cab started around. I stopped with the trailer truck right on the curve to see just how close to a big mess were. The sliding plates on the left side were way over, almost to the point of dropping off each other. I had the fireman watch as I eased back a bit more and things started to straighten out. I could see hitting that at any kind of speed would have made the plates slide apart, put the truck in a bind and put us on the ground.

Because a K-28 has its trailing truck axle under the engineer's seat, there is little overhang from the truck to the rear of the cab, so there was no backing issues.