# Perplexing steam engine question---



## Brian Rupnow (Jun 16, 2008)

This is a question that has hung in the back of my mind all my life. When I was a boy in the 1950's, steam trains used to come into the junction near where I lived. Although warned by my parents to stay away from the train yards, my curiosity about all things mechanical made that impossible. The big old steam engines had two cylinders, one on each side of the train, and when they shut the engines off, they would coast to a stop. The two cylinders were out of phase by 180 degrees, so that when one piston was at top dead center the piston on the other side of the train was at bottom dead center. What happened if they stopped in that position??? You can't flick the flywheel or push start a multi ton locomotive to get it moving, and in my experience when a piston stops at top or bottom dead center, no amount of steam is going to make things move.---What did they do to get the engines rolling over????????


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## te_gui (Jun 16, 2008)

Typically locomotives were 'quartered" 90 degrees vs 180 so would be self starting


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## rangerssteamtoys (Jun 16, 2008)

The Conductor was smart and NEVER made it where the pistons were like that. But I agree with te_gui becuase the 2 cylinder engines that I have seen were 90 degrees off.


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## Cedge (Jun 16, 2008)

Brian
Twin cylinder slide valve double acting engines are usually timed at 90° so that one end of a cylinder is always making a power stroke within the cycle. This allows them to be self starting rather than having the potential for stopping in a dead spot. 

Steve


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## Brian Rupnow (Jun 16, 2008)

Wouldn't that throw some strange harmonics into the drive---being timed at 90 degrees?


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## Tin Falcon (Jun 16, 2008)

typically for self starting you have two cylinders that are double acting so one cylinder i always at or near top dead center with the valve open ready to let in steam and start the engine. Basically what was already said.
Tin


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## kf2qd (Jun 16, 2008)

Some of those old steamers were 3 cylinder units - with the third one between the rails.

And I agree - the two sides of the engine were 90 degrees out of phase.


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## Cedge (Jun 16, 2008)

Brian
Since the eccentrics for each cylinder's slide valve are timed at 90° to the crank, you achieve a pretty fair balance.... and a power stroke every 1/4 turn of the crank shaft. You're more likely to get harmonic problems from a flywheel or drivers being unbalanced. 

Steve


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## Bernd (Jun 17, 2008)

Speaking of three cylinders, has anybody ever hear a Shay at top speed, which is about 10mph. Sounds like the dam thing is doing 150mph. Another neat sounding engine is the articulated steam engine that has 4 cylinders. Now theres a sound that's neat.

Bernd


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## ChooChooMike (Jun 18, 2008)

Bernd  said:
			
		

> Speaking of three cylinders, has anybody ever hear a Shay at top speed, which is about 10mph. Sounds like the dam thing is doing 150mph.



And sounds like a machine-gun at times.



> Another neat sounding engine is the articulated steam engine that has 4 cylinders. Now theres a sound that's neat.



Or double-headed steam loco's working hard uphill with a long consist. Had that run-by at Cumbres & Toltec 2 years ago - what a great sound ! The whole photo line gave the train guys a standing ovation ! :bow: They said that was the 1st time they had gotten such applause ! Well-deserved 

Mike


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## Bernd (Jun 19, 2008)

I've got a few sound records with steam engine sounds on them. There's nothing like the sound of a hogger pulling back on the throttle and starting over 100 empty hopper cars. Gives me goose bumbs just thinking about it. :big:

Bernd


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## Cedge (Jun 19, 2008)

CCMike
I had the pleasure of attending the first day's public operation of a freshly restored Shay at the Spencer Yards Rail Museum in Spencer, NC a few years back. They might be slow, but they have a distinctly robust sound that you aren't likely to forget.

I'll call your goose bumps and raise you my half naked butt running to watch the N&W 611 J whistle through the intersect next to my old bachelor apartment. I finally got the second leg in my pants while standing by the tracks....where there were about 50 people gathered.......LOL That old whistle could raise the hair on my neck and arms from 10 miles up the track.

Steve


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## dparker (Jun 20, 2008)

Hello All: My first memory of steam engines was in Great Falls Montana where my Grandfather was the Station Master and Telegrapher on the Millwaukie Line. I must have been about 4 years old and playing on the platform near the engine when the engineer blew down the cylinders and I was lost in a cloud of wet cool steam and loud noise. I believe I can still hear the engineer laughing. I think my Grandfather even got a kick out of it. Didn't really scare me so much as I thought it was kind of a rude thing to do to a little kid.
I now live in Portland OR where they rebuilt the Freedom Train engine for the Bicentenial and I got to see that go by where I worked in 1976 (big engine!)
don


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## Bernd (Jun 20, 2008)

Cedge  said:
			
		

> I'll call your goose bumps and raise you my half naked butt running to watch the N&W 611 J whistle through the intersect next to my old bachelor apartment.
> Steve



I got the 611 on video when a bunch of us went to Norfolk and chased her for two days. What a nice engine.

Bernd


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## Cedge (Jun 20, 2008)

Bernd
Then I don't have to tell you the effect that long moaning whistle has.

Steve


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## Bogstandard (Jun 20, 2008)

Steve,

Is that the same wailing sound as my wife makes when she asks for cash, makes the hairs stand up on the back of the neck ?

Bogs


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## Cedge (Jun 20, 2008)

John... 
Possibly... can she be heard at 10 miles over heavy traffic noise?

Steve


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## Bernd (Jun 21, 2008)

Cedge  said:
			
		

> Bernd
> Then I don't have to tell you the effect that long moaning whistle has.
> 
> Steve



No you don't. Or how quite that engine is drifting down hill because of roller bearings, no side rod clanking. 

Bernd


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