Small American Steam Locomotives

For the past year or so, I've been coming up with a steam locomotive design based on a small Welsh steam locomotive for a railroad that I hope to build someday. (Don't ask why I've been doing this for a year. I have no idea.) The design has gotten as far as it's going to get so far and I'm looking for another steam locomotive to build a design from. I would prefer a small steam locomotive of American design that would perform well on a narrow gauge (24 in. or 30 in.) railroad in mountainous terrain. Pictures if available.
 
A lot of logging locos are rather strange or one-off, with strange wheel arrangements like 2-4-0, 2-4-2 or shay's or climaxes. Consider making a 36in version, I love 36 in narrow-gauge.
 
Like this, perhaps?
Loco.jpg

Lyn-sml.jpg

91196.jpg

'Lyn' was a Baldwin 2-4-2T ordered by the Lynton & Barnstaple Railway in England. It was sent over as a kit of parts and assembled the the L&BR's workshop. It was extremely successful and more powerful than the larger 2-6-2Ts they had in service. It was broken up in 1935 when the L&BR closed, but a replica is now under construction. A (very good) model is available on the DLS.
I assume US narrow gauge railroads had similar or perhaps even identical locos.
 

Thank you for the abundance of pictures! EDIT: I think out of these two designs I would go with the Forney. The shorter wheelbase of the Forney would better suit it for sharper turns, plus the Forney it closer to the size I'm looking for.

Like this, perhaps?
Loco.jpg
Lyn-sml.jpg
91196.jpg
'Lyn' was a Baldwin 2-4-2T ordered by the Lynton & Barnstaple Railway in England. It was sent over as a kit of parts and assembled the the L&BR's workshop. It was extremely successful and more powerful than the larger 2-6-2Ts they had in service. It was broken up in 1935 when the L&BR closed, but a replica is now under construction. A (very good) model is available on the DLS.I assume US narrow gauge railroads had similar or perhaps even identical locos.
I had forgotten about 'Lyn'! I have that model of 'Lyn' downloaded, which I can't believe I forgot about!The U.S. had its own version of the 2-6-2 locomotives, so to speak. A railroad in Maine called (if I remember the name correctly) "Sandy River & Rangly Lake" had several 24 inch gauge 2-6-2 tender locomotives. And I believe Baldwin built similar locomotives in 36 inch gauge for some logging railroads.So what was it about the design of 'Lyn' that made it more powerful than the 2-6-2T's? Surely it wasn't weight?
 
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Thank you for the abundance of pictures! EDIT: I think out of these two designs I would go with the Forney. The shorter wheelbase of the Forney would better suit it for sharper turns, plus the Forney it closer to the size I'm looking for.

I had forgotten about 'Lyn'! I have that model of 'Lyn' downloaded, which I can't believe I forgot about!The U.S. had its own version of the 2-6-2 locomotives, so to speak. A railroad in Maine called (if I remember the name correctly) "Sandy River & Rangly Lake" had several 24 inch gauge 2-6-2 tender locomotives. And I believe Baldwin built similar locomotives in 36 inch gauge for some logging railroads.So what was it about the design of 'Lyn' that made it more powerful than the 2-6-2T's? Surely it wasn't weight?

Yeah, the Forneys were lquite the powerhouses even for their small size. When Edaville Railroad was still in existence, my family and I would visit and ride on their trains. They had a number of these in their collection which I believe has been moved back to Maine as part of the State Narrow Gauge Museum.

John
 
Togog made the Denver South Park & Pacific's 2-6-6T and 2-8-6T 3 foot gauge Mason-Bogeys. They are on the DLS. He also made some D&RGW 4-4-0's and 2-6-0's.

Ben
 
'Lyn' being more powerful was probably down to faults in the construction of the 2-6-2s. Plus, the fact it had fewer driving wheels would have increased grip, I guess. You'd have to ask an engineer for a concise answer.
 
Yeah, the Forneys were lquite the powerhouses even for their small size. When Edaville Railroad was still in existence, my family and I would visit and ride on their trains. They had a number of these in their collection which I believe has been moved back to Maine as part of the State Narrow Gauge Museum.

John

That picture of the Porter built Forney that you linked intrigued me. I didn't think they made Forneys (Forneys, Forneies, Forney's?) with saddle tanks.

Togog made the Denver South Park & Pacific's 2-6-6T and 2-8-6T 3 foot gauge Mason-Bogeys. They are on the DLS. He also made some D&RGW 4-4-0's and 2-6-0's.

Ben

I think I have one of Togog's Mason Bogie locomotives. I also have E&S No. 4 and some of his D&RGW 2-8-2's. He makes some pretty nice models!

'Lyn' being more powerful was probably down to faults in the construction of the 2-6-2s. Plus, the fact it had fewer driving wheels would have increased grip, I guess. You'd have to ask an engineer for a concise answer.

Hmmm, I wouldn't have thought that the fewer driving wheels would result in increased grip. Theoretically speaking, the driving wheels on 'Lyn' would have only carried half the weight of the locomotive (unless the pony trucks didn't carry as much weight as I think), compared to the driving wheels on the 2-6-2's carrying (theoretically) 3/5 (60%) of the weight. But since 'Lyn' only had four driving wheels instead of six, the weight on the axles wouldn't have been as dispersed as the 2-6-2's. (Which I guess would mean more power per axle?) Your guess is as good as mine!
 
Only FOUR?! I don't know about the UK, but in America, it would be pretty rare to see a doubleheaded train with only eight coaches. But that's not to say we haven't had similar things happen before.
 
As a rule only two factors get heavily involved in tractive effort. The weight on the drivers and the coefficient of adhesion between the steel drivers and the iron rails. Steel on iron isn't a particularly good combination but when it come to railroads there isn't much of a choice. Rubber on asphalt/concrete is much better (think they call them semis or something like that, lol).

Weight distribution (axel loading) is strictly a matter of weight per axle. The same weight on 2, 3, or 4 axles makes little difference except the adhesion would be a bit larger since more area of the drivers is in contact with more area of the rails.

Too much weight per axle can damage the rails. The Southern Pacific made some 2-6-0's from 2-6-6-2 parts but the axle loading was so high they couldn't be used on branch lines but a 2-6-0 was no longer suitable for main lines in the 1930's so they were scrapped.

Still - - - small locos look neat .

Ben
 
As a rule only two factors get heavily involved in tractive effort. The weight on the drivers and the coefficient of adhesion between the steel drivers and the iron rails. Steel on iron isn't a particularly good combination but when it come to railroads there isn't much of a choice. Rubber on asphalt/concrete is much better (think they call them semis or something like that, lol).Weight distribution (axel loading) is strictly a matter of weight per axle. The same weight on 2, 3, or 4 axles makes little difference except the adhesion would be a bit larger since more area of the drivers is in contact with more area of the rails.Too much weight per axle can damage the rails. The Southern Pacific made some 2-6-0's from 2-6-6-2 parts but the axle loading was so high they couldn't be used on branch lines but a 2-6-0 was no longer suitable for main lines in the 1930's so they were scrapped.Still - - - small locos look neat .Ben
So would each of the driving axles on a 2-4-2 carry the same amount of weight as the pony truck axles? (In other words, 50% of the weight on the drivers and 50% on the pony trucks.) Or does that depend?
 
No. The amount of weight on leading and trailing bogeys is far less then on the drivers. Leading and trailing bogeys are for other reasons. The weight on the drivers should (if properly designed) be equal. A 100 ton 0-8-0T should have 25 tons per axle. When you add leading and trailing bogeys it gets a bit complicated.

A lead bogey supports the front of the loco and helps lead the engine into curves. At some speed value a 4 wheel lead bogey is preferred over a 2 wheel lead bogey. Weight may be a consideration but speed is primary.

A trailing bogey supports the weight of the cab/firebox area and helps the loco enter curves when in reverse. Since steam locos don't go as fast in reverse (hopefully) the choice of 2 or 4 wheels is more concerned with the weight they must support then speed.

Both normal lead and trailing bogeys generate no tractive effort. A trailing bogey with a booster does but lets ignore that for the purposes of this discussion. They also have weight applied to them. This weight is not available to the drivers so does not add any tractive effort. If a wheel (axle) isn't driven it generates no tractive effort.

Ben
 
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The D&RG had a double Fairlie (0-4-4-0) named Mountaineer. Got it in 1873 and scrapped at in 1887. Its the only Fairlie I have ever heard of on US roads (which doesn't mean there might not be others but if so they are few and far between).

Togog has made this loco and it is on the DLS.

Ben
 
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No. The amount of weight on leading and trailing bogeys is far less then on the drivers. Leading and trailing bogeys are for other reasons. The weight on the drivers should (if properly designed) be equal. A 100 ton 0-8-0T should have 25 tons per axle. When you add leading and trailing bogeys it gets a bit complicated.A lead bogey supports the front of the loco and helps lead the engine into curves. At some speed value a 4 wheel lead bogey is preferred over a 2 wheel lead bogey. Weight may be a consideration but speed is primary.A trailing bogey supports the weight of the cab/firebox area and helps the loco enter curves when in reverse. Since steam locos don't go as fast in reverse (hopefully) the choice of 2 or 4 wheels is more concerned with the weight they must support then speed.Both normal lead and trailing bogeys generate no tractive effort. A trailing bogey with a booster does but lets ignore that for the purposes of this discussion. They also have weight applied to them. This weight is not available to the drivers so does not add any tractive effort. If a wheel (axle) isn't driven it generates no tractive effort.Ben
Ah, I see. I knew that the trailing truck had weight on it, but I didn't know how much. So basically, if I wanted to get the most tractive effort out of my locomotives (which are so far a 0-4-2 and most likely a 0-4-4ST), I would need booster units (besides adding more weight, compounding, etc.).
 
The D&RG had a double Fairlie (0-4-4-0) named Mountaineer. Got it in 1873 and scrapped at in 1887. Its the only Fairlie I have ever heard of on US roads (which doesn't mean there might not be others but if so they are few and far between).

Togog has made this loco and it is on the DLS.

Ben
All Mason Bogies were single Fairlies. As I recall, Mason licensed the Fairlie design. When you include the Mason Bogies, Fairlies were not uncommon in the US, but they only had a relatively brief period of popularity (as I recall, this was between the 1870s and 1890s, with a few exceptions [for the Boston, Revere Beach & Lynn] built by ALCo as late as the 1910s.)

Cheers,
Ben
 
Ah, I see. I knew that the trailing truck had weight on it, but I didn't know how much. So basically, if I wanted to get the most tractive effort out of my locomotives (which are so far a 0-4-2 and most likely a 0-4-4ST), I would need booster units (besides adding more weight, compounding, etc.).
Booster units were mostly used on standard gauge locos, due to the increased space between the frames of the trailing wheels the boosters were applied to.
Most narrow gauge railroads in the US seemed to try their best to avoid costly things and use designs that were easy to perform maintenance on, which the trailing wheel boosters were neither cheap nor easy to maintain.

Here's Wikipedia's article on the subject: http://en.wikipedia.org/wiki/Booster_engine

If you want more tractive effort, the best solution for a narrow gauge loco would be more weight on the driving wheels. Usually, that would mean less leading/trailing wheels and more driving wheels. But because narrow gauge railroads generally have sharp curves, more driving wheels means less of an ability to negotiate them.
 
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