Locomotive transmission.

steamman

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A gas pedal on a car can be used to speed up and slow down, a transmission improves gas mileage and add reverse. A locomotive had something like a transmission although unlike a transmission it did not pass power.


Walschaerts valve gear
https://en.wikipedia.org/wiki/Walsc.../en.wikipedia.org/wiki/Walschaerts_valve_gear

The Walschaerts valve gear is a type of valve gear invented by Belgian railway mechanical engineer Egide Walschaerts in 1844 used to regulate the flow of steam to the pistons in steam engines. The gear is sometimes named without the final "s", since it was incorrectly patented under that name. It was extensively used in steam locomotives from the late 19th century until the end of the steam era.




Similar to the Walchaerts is the Johnson reverser.

Seen in action in this video starting at 1:30

Stephenson was an earlier method.
https://en.wikipedia.org/wiki/Stephenson_valve_gear


_P52ZVbnxbY83eF_qT07i2BYgI-F6n2f9Cdysx9sLsBcRH5Kob.jpg


Inside Stephenson valve gear as applied to a French 0-6-0 outside cylinder mixed traffic locomotive (Midi 801) in 1867

In 1841 two employees in Stephenson's locomotive works, draughtsman William Howe and pattern-maker William Williams, suggested the simple expedient of replacing the gabs with a vertical slotted link, pivoted at both ends to the tips of the eccentric rods. To change direction, the link and rod ends were bodily raised or lowered by means of a counterbalanced bell crank worked by a reach rod that connected it to the reversing lever. This not only simplified reversing but it was realised that the gear could be raised or lowered in small increments, and thus the combined motion from the “forward” and “back” eccentrics in differing proportions would impart shorter travel to the valve, cutting off admission steam earlier in the stroke and using a smaller amount steam expansively in the cylinder, using its own energy rather than continuing to draw from the boiler. It became the practice to start the engine or climb gradients at long cutoff, usually about 70-80% maximum of the power stroke and to shorten the cutoff as momentum was gained to benefit from the economy of expansive working and the effect of increased lead and higher compression at the end of each stroke. This process was popularly known as "linking up" or “notching up”, the latter because the reversing lever could be held in precise positions by means of a catch on the lever engaging notches in a quadrant; the term stuck even after the introduction of the screw reverser. A further intrinsic advantage of the Stephenson gear not found in most other types was variable lead. Depending on how the gear was laid out, it was possible to considerably reduce compression and back pressure at the end of each piston stroke when working at low speed in full gear; once again as momentum was gained and cutoff shortened, so lead was automatically advanced and compression increased, cushioning the piston at the end of each stroke and heating the remaining trapped steam in order to avoid temperature drop in the fresh charge of incoming admission steam.
 
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Waterloo50

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@steamman thanks for posting the info on locomotive transmission, it’s fascinating stuff, I’m actually learning quite a bit, so far you’ve covered riveting/boilers/ cylinders and transmission, any chance that you’ll start a thread on how these locomotives were operated. A few years ago I spent some time with a retired engineer from the Great Western Railway and we spent a good hour in the cab whilst he explained to me how to drive a steam locomotive, it looks easy but it most definitely isn’t, those engineers had a massive amount of skill and knowledge, the engineer told me that he had to know every single mile of the route, knowledge which he’d gained over years as an apprentice fireman. Interestingly he reckoned that he could drive a route blindfolded and know exactly where he was due to the motion and sound of the loco.
 

steamman

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@steamman thanks for posting the info on locomotive transmission, it’s fascinating stuff, I’m actually learning quite a bit, so far you’ve covered riveting/boilers/ cylinders and transmission, any chance that you’ll start a thread on how these locomotives were operated. A few years ago I spent some time with a retired engineer from the Great Western Railway and we spent a good hour in the cab whilst he explained to me how to drive a steam locomotive, it looks easy but it most definitely isn’t, those engineers had a massive amount of skill and knowledge, the engineer told me that he had to know every single mile of the route, knowledge which he’d gained over years as an apprentice fireman. Interestingly he reckoned that he could drive a route blindfolded and know exactly where he was due to the motion and sound of the loco.
One of the YouTube videos is about operation and I found it complicated. With experience the sounds and motions would make for clues. Managing all the controls would be second nature.

I'll try to get a step by step getting steam up and running an locomotive set of posts.
 

Waterloo50

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Very much in the nature of apprenticeship to learn a trade. That had been around since ancient times.
My GG grandfather started his apprenticeship as a locomotive cleaner, then he became a fireman and he was eventually promoted to permanent fireman, after many years as a fireman on the railroad he managed to achieve the lofty statues of driver. Here’s a pic of my GG grandfather with his pride and joy.

you can tell that he was a driver because of the status symbol on top of his head, a bowler hat was very rarely worn by the working class, business men and managers were the ones that ordinarily wore bowler hats, drivers were seen as high status employees and were highly respected for their skills. I think this photo would have been taken in the late 1920s, this particular locomotive was retired from service in the early 1930s.

He worked for the S&D (Somerset and Dorset Railway) the S&D became known as the slow and dirty.
0841B2A2-3D8F-4942-856C-3F17FE18CD54.png
 
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Lubliner

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The right to be proud @Waterloo50, that is a cool picture. He looks to be about 40 years of age. Slow and dirty, you say!:rofl:
I met some men that worked for the railroads running into Kentucky. They get trained and have to take a test on the Locomotive. One started out as a shuttle runner driving a van. It seems there were no free rides on the train.
Lubliner.
 

Waterloo50

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The right to be proud @Waterloo50, that is a cool picture. He looks to be about 40 years of age. Slow and dirty, you say!:rofl:
I met some men that worked for the railroads running into Kentucky. They get trained and have to take a test on the Locomotive. One started out as a shuttle runner driving a van. It seems there were no free rides on the train.
Lubliner.
Absolutely (slow and dirty) the amount of soot from coal fired engines was horrific and the engines used on the S&D were tired old things, coupled with the steep gradients it’s a wonder that the company lasted as long as it did. Some of the climbs were so steep that the S&D used banking engines just to give a little shove at the rear of the train. It must have been a fantastic sight and sound to see those old steam engines working hard just to get to the top of a climb. Just out of interest, the USA preferred wood fired engines over coal, did they produce a lot of soot or were they cleaner?
 

Lubliner

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Absolutely (slow and dirty) the amount of soot from coal fired engines was horrific and the engines used on the S&D were tired old things, coupled with the steep gradients it’s a wonder that the company lasted as long as it did. Some of the climbs were so steep that the S&D used banking engines just to give a little shove at the rear of the train. It must have been a fantastic sight and sound to see those old steam engines working hard just to get to the top of a climb. Just out of interest, the USA preferred wood fired engines over coal, did they produce a lot of soot or were they cleaner?
In the Official Records, Navy, they frequently request a certain coal density (?) that puts off less soot, and easier to clean out of the fire-box. Two different grades of coal were available.
Lubliner.
 

DaveBrt

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Absolutely (slow and dirty) the amount of soot from coal fired engines was horrific and the engines used on the S&D were tired old things, coupled with the steep gradients it’s a wonder that the company lasted as long as it did. Some of the climbs were so steep that the S&D used banking engines just to give a little shove at the rear of the train. It must have been a fantastic sight and sound to see those old steam engines working hard just to get to the top of a climb. Just out of interest, the USA preferred wood fired engines over coal, did they produce a lot of soot or were they cleaner?
American railroads almost all used wood until about 1870, when the change to coal really got started.

Wood produced huge amounts of smoke, filled with embers. The likelihood of fire from the embers drove many things -- the shape of the locomotive smoke stack, tin on car roofs, tin on roofs of company buildings, passenger cars at the tail of the train (away from the smoke and chance of setting clothing on fire). Once the cheap and local wood was used up, and the greater economy of coal was proven, roads were quick to change over. I'm sure few people were sorry to see the change.
 

Waterloo50

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American railroads almost all used wood until about 1870, when the change to coal really got started.

Wood produced huge amounts of smoke, filled with embers. The likelihood of fire from the embers drove many things -- the shape of the locomotive smoke stack, tin on car roofs, tin on roofs of company buildings, passenger cars at the tail of the train (away from the smoke and chance of setting clothing on fire). Once the cheap and local wood was used up, and the greater economy of coal was proven, roads were quick to change over. I'm sure few people were sorry to see the change.
Thanks for the info, another question on the engines that switched from wood to coal, did they require upgrading or did they switch over without any drastic changes?

on another note, I see that you live in Charlotte NC, I’ve been looking at photos of a place called Linwood yard but I’ve noticed that some people call it Spencer yard, it’s apparently one of the last remaining hump yards. Looks like an interesting place, sadly there’s no rail cam there, there was a live cam at Thomasville but that’s not running anymore, most of the cams that are running show mostly CSX, occasionally I’ve seen the NS trains and they definitely have the best livery.
 

DaveBrt

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Thanks for the info, another question on the engines that switched from wood to coal, did they require upgrading or did they switch over without any drastic changes?

on another note, I see that you live in Charlotte NC, I’ve been looking at photos of a place called Linwood yard but I’ve noticed that some people call it Spencer yard, it’s apparently one of the last remaining hump yards. Looks like an interesting place, sadly there’s no rail cam there, there was a live cam at Thomasville but that’s not running anymore, most of the cams that are running show mostly CSX, occasionally I’ve seen the NS trains and they definitely have the best livery.
Coal burned hotter, so the fireboxes and grates had to be upgraded. Mostly, it was a case of replacing wood burners with newer, more powerful, coal burners (not that the coal burning made them more powerful).

Spencer is the location of the NC Transportation Museum, check it out if you have not seen it.
 

Lubliner

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@Waterloo50 asked the question I had, but I have one step further now. When the trains changed to oil, what was the procedure? The video I posted on those two 1897 and 1901 locomotives in the woods of Maine, they man showing the two attached fuel cars mentioned the changeover for carrying oil. I would think no use for a firebox if that was so, @DaveBrt.
Lubliner.
 

DaveBrt

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@Waterloo50 asked the question I had, but I have one step further now. When the trains changed to oil, what was the procedure? The video I posted on those two 1897 and 1901 locomotives in the woods of Maine, they man showing the two attached fuel cars mentioned the changeover for carrying oil. I would think no use for a firebox if that was so, @DaveBrt.
Lubliner.
I would assume you are right, but it is past my Civil War research to know for sure.
 

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