I've heard old-timers talk about steam locos in the same class on a RR having different personalities. Some rode rough, some smooth, etc. Apparently, the manufacturing process for these machines left plenty of variability between each "identical" copy sent out the factory door. I heard it again today when someone on Trainorders said that the preserved SP Cab Forward at Cal State Ry Museum was the worst riding of its class.

When steam locos are restored in the modern day, a lot of defects such as bent frames, crap welds, bad springs and such are noticed and corrected. Do these fixes change the loco's operating personality much?

Someday the SP Cab Forward might be made operational. If it happens, should they preserve its rough riding quality given the option to improve it?

Some issues last due to the component that creates it. TVRM 610 has always had a sticky throttle. The ATC crews hated it so much that they'd only use the 610 if there was no other locomotive available. Nothing TVRM has done to the locomotive has improved that significantly.

Some defects such as faulty welds and bad springs can be corrected such that the issue disappears. Correcting a bent frame without replacing a major part will reduce the effect, but may create additional effects.

A good example is that of the ten-wheelers on the ET&WNC. They used Baldwin 3-footer 4-6-0s through the later years of the operations. Through 1943 they had three, #s 9, 11 and 12 (10 and 14 had been shipped to the WP&Y and burned in a roundhouse fire near the end of the war). While # 9 was similar, it was from a different class than 11 and 12. But the latter were the same type of engine. Only some smokebox work from a head end collision years before to 12 was the only difference between them to speak of.
While # 12 exists today pulling trains at Tweetsie RR, # 11 was the one the crews liked to run. It pulled the last train in 1950. 9 had bene scrapped by then. Ironically, that was the one to get scrapped after they shut down the 3-foot portion of the line. But the crews claimed that 11 was the better of the apparently 'identical' engines.
Stories like this abound in RR lore...

My Dad always supported that theory. He was a Frisco engineer and often said that certain engines would have more pleasant characteristics than others in the same class. I suspect you will find the same thing with most mechanical items.

A friend's Grandfather was a engineer for one of the Canadian Roads, CP or CN I forget which, the story was told about one of several identical engines that he ran, was always impossible to "hook up" when under heavy load, the fireman would always have to come over and help the engineer. They never figured out the cause, compared measurements against the other engines in the class, nothing.

-Hudson

In today's world all you have to do is look at the CO ng lines. Both the C&TS and D&S operate multiple examples of the same class of locomotives.

I worked for the C&TS for about 20 years and the 4 K36 class engines had their own quirks, pluses and minuses.

484. Drafted real hard out of the back of the firebox. It seems one was always putting coal in the back corners and under the door. Steamed OK, but used more coal and water to get the work done. Injectors seemed to be more troublesome than they should have been. Good throttle, valve gear was so-so, went dead 4 notches from center. Ride was OK once the out of quarter #4 driver was sorted out.

487. An odd duck to fire. Easy to slug. If the stack is black - SIT DOWN, and wait for it to clear before adding more coal. She wouldn't run as clear a stack as the others, but if you did things her way (heavy down the sides and under the door, real light down the center) she would do whatever you wanted her to do, A real good runner, good throttle, could hook her up to 3 notches of center and she sail right along. Some said she did not pull very well, but I thought she did just fine. My fastest runs ever on the NG were on 487.

488. Ate lots of coal. Seemed to draft harder than the rest, and lit more fires than the rest. If you had a deeper fire in her she would steam OK. For a long time she had an oversized injector on the left side, which more than kept up climbing the steep side of Cumbres. The trade off was coming up the gentler east side, you'd have to run it until she filled up, then kill the gun and ride along with a real thin fire while the water dropped to 1/2 a glass or less, then build up a big fire again, start the gun and trim it back as far as you could and go until she filled up again. The other engines had smaller injectors that if run correctly would not only keep up on hard pulls, but could be cut back to a tiny dribble on the east side of the hill. 488 didn't ride as well, and the cab rattled badly. The throttle was stiff to open and was always creeping closed. Never bonded well with 488.

489. Queen of the fleet. Fired easy, injectors always worked well, rode real well, had good square valve gear that would run all day 2 notches from center. She had more "snap" to her, I think because she had a bit more lead on her valves. Great throttle. Pulled well and seemed to have a crisper voice than the rest (better valve rings). Always felt nice and tight, even when really worn out. She did have an pilot truck issue in that she seemed to hunt more than the others. All Round Good Mill and will always be my favorite.

This applies to more than steam locomotives and to some extent beyond mechanical devices. I've three of the same model and year mid 1990's auto, and each one has been different and each one changed as the miles added up.

Perhaps more oddly, any decent computer system administrator who overseas more than a couple of dozen servers can usually tell you which boxes are dogs. We once gave up after two years with a high end, three letter manufacturer over two very high end computer systems that ran the same exact software with a 15% different in performance.

Bob

On the traction side of things, we have two Toronto PCCs from the 4600-class rebuilds. TTC 4603 responds well to the accelerator and braking. TTC 4602 seems a bit sluggish in response to the pedals for acceleration and braking. Same Westinghouse gear on both cars. Makes no sense, just as Earl's experiences with the 480's on C&TS.

Wesley

The same thing can be said about model live steam locomotives as well, no matter how small! My now deceased partner and I once sold Mamod live steam locomotives in 16mm scale. EVERY last one of them we came into contact with had its own quirky personality, and no two ever behaved exactly alike! And no matter how closely alike parts were machined and fitted, each engine seemed to have a mind of its own when fired.

All this goes to reinforce the fact that the iron horse is a living, breathing being. I've not had the great fortune to fire or be on locomotives of the same class but I have done so on traction engines. The story is the same - each has its own personality. Some are real pussycats and some are just looking for the opportunity to reach around and bite you in the a@@.....mld

Having never run a steam locomotive myself (save for a small live steamer) I don't really have any experience with any locomotive's personality per se, but I have heard/read about some locomotives personalities.

London & Northeastern Railway 4468 Mallard was described by some Southern Railway engineers (or engine drivers as they call them in the UK) during the 1948 exchange trials as being "highly-strung," though I haven't come across the exact reason as to why she was described in that way.

New Hope & Ivyland 1533 from what I've heard was a very easy locomotive to run and fire and was apparently a "friendlier" for lack of a better word, then 40 was/is.

I seem to remember reading the article on the two Berkshires delivered to the TH&B that was printed in Trains magazine that the two had very different personalities and that one would lug more tonnage than the other. This phenomena is not limited to steam, as I have ridden dozens (hundreds?) of SD-40-2 locomotives and all are a different animal, some have really good riding characteristics and strong dynamic brakes, while others are rough riding SOBs with questionable DB. As they age the differences between them become more pronounced.

Diesel electric locomotives are no different. All three of the F40s at Grand Canyon Railway behave in their own unique manners.

These cars have a device that measures the amount of current flowing into the motors. It controls the acceleration. These devices are adjustable. If both are adjusted to the same value, I suspect car performance will become similar. Some museums with PCC cars have adjusted them to reduce the maximum amount of current drawn to prevent overloading a marginal power supply. The metering device has an external shunt. If it has been replaced with a different value, car performance will change.

Shoreline (formerly Brannford) Trolley Museum had six cars with identical motors and K-type controllers. They all handled differently.

A man I knew who had been a motorman with Market Street Railway in San Francisco hated one particular car. If he was assigned to it, he would run it on resistance points until it quit so he could turn it in for a different car. He never was caught although another person saw him going uphill on Mission street with all the resistance grids glowing.

So even the old trolleys had different personalities.

Slight topic drift.

One of our retirees from DC Transit told the story of how the dispatcher of the Western division would put a "dog" car on the track to discourage operators from making unnecessary turn-ins such as you describe here.

Wesley