Imaginary Locomotives

[Andy Kirkham]

Just looking back at the initial post of this popular thread, I see that the OP was not primarily interested in fictional classes; one of the things he mentioned was additional members of real classes. Perhaps this is not practical; it would depend whether plate manufacturers were prepared to accept one-off orders for fictional names and numbers.

 

I think it is noteworthy that modellers are happy to invent whole towns that never existed, but are unwilling to take the much lesser leap of the imagination to invent extra locos.

[Northmoor]

30 minutes ago, Andy Kirkham said:

Just looking back at the initial post of this popular thread, I see that the OP was not primarily interested in fictional classes; one of the things he mentioned was additional members of real classes. Perhaps this is not practical; it would depend whether plate manufacturers were prepared to accept one-off orders for fictional names and numbers.

 

I think it is noteworthy that modellers are happy to invent whole towns that never existed, but are unwilling to take the much lesser leap of the imagination to invent extra locos.

It does seem to be a strange aspect of so many railway modellers that they will take the most unbelievable liberties with geography, geology and architecture - to name just three, let's not start on things like track gauge - but god forbid that a locomotive is operated with the wrong number.

[PhilJ W]

47 minutes ago, DK123GWR said:

On the perennial favourite subject of banking locomotives, could an articulated geared steam locomotive have been of use in this or any other role in Britain? They seem to have been more popular in North America, which might indicate that operating conditions or loading gauge prevented their effective use elsewhere, although I believe Avonside built a few narrow gauge examples for export (and Kirklees Light Railway/Whistlestop Valley have a 15inch gauge loco based on the Avonside them).

Geared locomotives were better for poorly laid and/or temporary track. On a properly laid main line in the UK they would only add further complication and expense for no gain

[JimC]

40 minutes ago, Andy Kirkham said:

I think it is noteworthy that modellers are happy to invent whole towns that never existed, but are unwilling to take the much lesser leap of the imagination to invent extra locos.

Especially when one considers that if the railway had an extra route serving their fictional town they would necessarily have had to have extra locomotive(s) to run the services to it.

[MikeOxon]

2 hours ago, JimC said:

Especially when one considers that if the railway had an extra route serving their fictional town they would necessarily have had to have extra locomotive(s) to run the services to it.

My own model is based on a planned but never-built branch through North Leigh to Witney.  Its extra locomotives include my interpretation of Dean's 4-2-4T, No.9, which pulls a selection of carriages to unknown GWR diagrams that, somehow, were accurately created by Tri-ang as a rake of clerestories

[john new]

On 02/09/2021 at 15:03, JimC said:

Especially when one considers that if the railway had an extra route serving their fictional town they would necessarily have had to have extra locomotive(s) to run the services to it.

Although it was a totally impractical design somewhere on the forum (possibly even in the early part of this thread) is the GWR's fictional branchline class commissioned from Hunslet just after WW2 and before nationalisation. If i was doing it again the back end would be slightly lengthened as the second of the powered bogies in the articulated 0-4-4-0 would have fouled the ash pan and would have had to be set further back. Looked OK though as a spoof on the SLS Christmas card for 2016 it was drawn for. The aim flexible for the tight radius curves on fictional branchlines, all wheels powered with plenty of grunt from 4 cylinders with small wheels to assist up the steep gradients also found on so many of the GWR's fictional branchlines.

 

Edit: added the image as I can't find a link to the original Xmas 2016 posting plus some extra text.

 

 

Edited April 15, 2022 by john new
Image(s) reloaded post site crash.

[ScottishRailFanatic]

In response to notes on my dual-cab 08, here’s a new bogie version. Along with that, here’s an Avonside-Peckett crossover 0-6-0ST.

[rockershovel]

5 hours ago, DK123GWR said:

On the perennial favourite subject of banking locomotives, could an articulated geared steam locomotive have been of use in this or any other role in Britain? They seem to have been more popular in North America, which might indicate that operating conditions or loading gauge prevented their effective use elsewhere, although I believe Avonside built a few narrow gauge examples for export (and Kirklees Light Railway/Whistlestop Valley have a 15inch gauge loco based on the Avonside them).

The Americans had a lot of experience of them, and clearly didn't regard them as suitable for the task. 

[sir douglas]

2ft gauge vertical boiler meyer

[The Johnster]

5 hours ago, DK123GWR said:

On the perennial favourite subject of banking locomotives, could an articulated geared steam locomotive have been of use in this or any other role in Britain? They seem to have been more popular in North America, which might indicate that operating conditions or loading gauge prevented their effective use elsewhere, although I believe Avonside built a few narrow gauge examples for export (and Kirklees Light Railway/Whistlestop Valley have a 15inch gauge loco based on the Avonside them).

You mean Shays, Climaxes, and so on?  Not really; their purpose was heavy haulage on logging railways and similar, where speed was not an issue; they would have by and large been too slow to operate on running lines even as bankers, where they'd have got in the way coming back down the bank light engine.  This does not mean that a geared loco suitable for banking could not have been devised, just that one never was because existing types were up to the job.

[ScottishRailFanatic]

I do often wonder why a Shay or Climax was never geared for speed, while sacrificing some of their admirable strength in the process…

[Curlew]

15 minutes ago, ScottishRailFanatic said:

I do often wonder why a Shay or Climax was never geared for speed, while sacrificing some of their admirable strength in the process…

Shays are inherently unbalanced due to an offset boiler.

 

I understood that Climax locos could be relatively nippy

[sir douglas]

the whole point of the off centre boiler is to balance having all the cylinders on one side, they are balanced

Edited September 2, 2021 by sir douglas

[DK123GWR]

22 minutes ago, Curlew said:

Shays are inherently unbalanced due to an offset boiler.

 

I understood that Climax locos could be relatively nippy

If Wikipedia is to be believed (I'm often hesitant about trusting it for technical matters - especially for what is perhaps best described as a niche area of interest) then the Heislers were often the fastest of the geared locos.

https://en.wikipedia.org/wiki/Heisler_locomotive

[DenysW]

Back to du Bousquets, I'm afraid.

 

Firstly, I suspect rovershover is confusing the SG of coal (agreed, around 1.26 to 1.4, dimensionless, depending on grade) with the effect of its bulk density, which includes the effect of all the air-gaps. Perfect spheres (I used to have to know this) have a bulk density 67% of their true SG. A liquid has 100% of its SG. Real-world solids are between these numbers, depending on how much the small bits fall into the gaps, and whether the shapes allow better packing than spheres that just-about kiss where they touch, and how much effort the fillers have put into bedding-down the solids. Think of slate.  Then think of pouring ground coffee into a jar, then watching it settle if you tap it. The internet suggested value for coal is 750-850 kg/m3, giving 6-6.5 m3 for 5 tonnes of coal. So I should have checked more closely but wasn't that far out.

 

Secondly: French Wikipedia (below) - inasfar as one believes Wikipedia - resolves that the front water tanks travelled with the front sets of driving wheels - as: 'ainsi que les caisses à eau avant'. It also says that the coal bunker was on the main chassis. This could be that Flying Pig's belief was fully right, or that the rear enclosure had some coal, and the rest was in the side-tank that wouldn't impede the driver, or that the rear 'caisses' both had coal in them (as I thought at first). I've only seen one du Bousquet picture that had something heaped up above the hand-rails at the rear, so I'm tending towards two coal stores - one conventionally at the rear of the tank locomotive, and one on one side in a rear tank. The two-store, neither person was right, version of the truth.

 

Some pictures have different filling fittings for the front tanks compared to the rear tanks. I think this just makes me more open to alternative opinions, than it makes me shout 'I woz right!'.

 

French Wkipedia:

 

"Les 031+130 étaient donc articulées selon le principe Meyer-Kitson et se composaient de trois éléments : un châssis constitué d'une poutre centrale portant l'ensemble chaudière-foyer-abri et réserve de charbon, deux trucks portant chacun un ensemble moteur avec cylindres reliés au châssis par des pivots à glissière permettant un débattement suffisant.

La locomotive étant de type compound à 4 cylindres, le truck arrière portait les cylindres à haute pression et le truck avant portant les cylindres basse pression ainsi que les caisses à eau avant. Pour assurer des conduites articulées courtes avec rotules, douille et fourreau, les cylindres HP et BP se faisaient face. Les tuyaux d'échappement reliant les cylindres BP à l'échappement étaient en toile caoutchoutée qui se révéla suffisamment résistante. L'échappement était du type « Nord » à cône mobile.

En service la machine pouvait s'inscrire dans des courbes de 90 m de rayon et la vitesse limite était fixée à 90 km/h."

[john new]

49 minutes ago, The Johnster said:

You mean Shays, Climaxes, and so on?  Not really; their purpose was heavy haulage on logging railways and similar, where speed was not an issue; they would have by and large been too slow to operate on running lines even as bankers, where they'd have got in the way coming back down the bank light engine.  This does not mean that a geared loco suitable for banking could not have been devised, just that one never was because existing types were up to the job.

 

It has always slightly puzzled me that given the inclines like Bincombe, Shap, Worsborough, the Lickey etc,, where so many trains took on banking engines that on at least one of them none of the companies tried a rack option. Would that not have been more suitable for the assisting engines than just adhesion? Is there an obvious drawback, perhaps speed when pushing using rack, that stopped the option being trialled here.

[DenysW]

Geared Locomotives.

 

I think the lack of UK interest may simply have been that no-one was selling them to the industrial users who potentially wanted something that had much more power than its boiler implied (thus less out-of-service running costs when you have to keep it stoked just stop the grate from cooling down), could run on poorly laid, often temporary lines, and where speed was a non-factor. Have a look at the 0-4-4-0 Garratts, that had a vendor, and even they were a hard sell with few takers.

 

The key shortage was that none of these had a commercially viable version that allowed the operator to change the gearing ratio. A lack for the steam-turbine locos, but that's another topic.

[DenysW]

Rack locos.

 

I agree with John New, but particularly for the Worsborough Bank. It had mining subsidence as well as its civil design issues, and a rack would have shifted as the ground shifted. Some of the accounts of the Worsborough imply that stalling on the even-steeper section pulling out of subsidence track was a routine cause of failure/problems.

[DK123GWR]

4 minutes ago, john new said:

 

It has always slightly puzzled me that given the inclines like Bincombe, Shap, Worsborough, the Lickey etc,, where so many trains took on banking engines that on at least one of them none of the companies tried a rack option. Would that not have been more suitable for the assisting engines than just adhesion? Is there an obvious drawback, perhaps speed when pushing using rack, that stopped the option being trialled here.

Perhaps it's overkill, given that racks are often used for gradients in excess of 10%, far steeper than any of the inclines named. Given the associated infrastructure costs, I can't see any railway using a rack unless absolutely essential. Wikipedia suggests that 15mph is a typical top speed, and 25mph on the fastest systems.

[PhilJ W]

17 minutes ago, DenysW said:

Geared Locomotives.

 

I think the lack of UK interest may simply have been that no-one was selling them to the industrial users who potentially wanted something that had much more power than its boiler implied (thus less out-of-service running costs when you have to keep it stoked just stop the grate from cooling down), could run on poorly laid, often temporary lines, and where speed was a non-factor. Have a look at the 0-4-4-0 Garratts, that had a vendor, and even they were a hard sell with few takers.

 

The key shortage was that none of these had a commercially viable version that allowed the operator to change the gearing ratio. A lack for the steam-turbine locos, but that's another topic.

What about the Sentinel shunters? They were geared and had vertical water tube boilers and were quite successful. 

[The Johnster]

Rack systems are used on very much steeper gradients than those mentioned, and even steeper than 1 in 14 (Hopton, Gelynos) which I believe were the steepest adhesion worked banks in the UK.  I believe a limitation is that the rack and the pinion on the loco are subject to very heavy wear if the loads are anything other than extremely light; the Snowdon Mountain Railway features single coach trains pushed uncoupled up the incline, which is about 1 in 7, isn't it? 

 

Racks are most common in the Alpine region, and some standard gauge sections on which 'normal' trains are hauled exist, but Alpine railways tend to be a bit extreme.  The solution in the UK to a gradient that could not be worked by adhesion was usually to use cable haulage, sometimes complete with the train locomotive as part of the load (Cowlairs, Pwllrehebog). 

Edited September 2, 2021 by The Johnster

[Flying Pig]

4 hours ago, john new said:

If i was doing it again the back end would be slightly lengthened as the second of the powered bogies in the articulated 0-4-4-0 would have fouled the ash pan and would have had to be set further back.

 

 

Flip the rear bogie and put an auxiliary exhaust in the extended bunker for the full Kitson-Meyer experience.  Of course, the cost of two copper caps would probably make it uneconomical to build.

[ScottishRailFanatic]

A rather unconventional 0-6-4T design, meant to represent an outside-cylinder version of the Midland Railway’s ‘Flatiron’ class…

[Compound2632]

1 hour ago, ScottishRailFanatic said:

A rather unconventional 0-6-4T design, meant to represent an outside-cylinder version of the Midland Railway’s ‘Flatiron’ class…

 

Not exactly a Chapelonesque steam circuit and plenty of mass over the bogie to reduce adhesion. But nice and toasty in the cab, I should think.

 

This is an outside-cylinder Flatiron, if you really want one:

 

Edited September 3, 2021 by Compound2632

[PhilJ W]

2 hours ago, ScottishRailFanatic said:

A rather unconventional 0-6-4T design, meant to represent an outside-cylinder version of the Midland Railway’s ‘Flatiron’ class…

As @Compound2632 said the cab would be rather warm and it would require very long pipes to deliver the exhaust to the chimney.