brains Wrote:
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> Hi PDX - Got to ride behind a "Merchant Navy"
> Bulleid on the Swanage (preserved) Railway in
> southern England. Great stalk talk.
> Odd the American bias against inside cylinders
> and crank axles and attendant valve train.
> Increased output vs. increased maintainance.

the UP, SP and D&RGW, for examples, had 3 cylinder steam locomotives. Both the UP and SP considered their 3 cylinder 4-12-2s and 4-10-2s, respectively quite successful, and the operated/lasted right to the end of steam. That said, the next step above 3 cylinder locomotives was the simple articulated, i.e. the 4-6-6-4, which markedly out performed any and all 3 cylinder locomotives in the U.S., and the world for that matter. What with the restricted clearances and light axle loadings in the UK and Europe, the big high HP U.S. articulated locomotives could not have been built nor used there. The bottom line; 4 cylinders and better than 3 cylinders, with a LOT less labor and maintenance on that center cylinder!