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Imaginary Locomotives


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2 hours ago, John Besley said:

That'll upset all those who've built TMD and have all their locos on tick over at an exhibition.... all we will hear now is a faint hiss...

And everyone would look at each other thinking who's f@rted.

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The technology for chemical steam generation goes back  over 100 years. By mixing 80 percent hydrogen peroxide and 20 percent water with hydrazine hydrate, methyl alcohol and water the chemical reaction produces heat (about 2,000 degrees centigrade) and water and therefore steam, this was used to power the Messerschmitt Me 163 Komet fighter. A development of this technology that was being worked on by the Germans at the end of WW2 was to power a U-boat with the steam being used to power a turbine to drive the vessel and generate electricity. The biggest problem was the chemicals were highly dangerous and needed careful handling. The other problem was that the reaction was difficult to control, the Me 163 pilots were sitting on a rocket over which they had very little control until it became a glider when the fuel ran out.

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On 11/06/2024 at 18:56, John Besley said:

There's the usual moronic comments from those who see a conspiracy everywhere and more from people with very little technical knowledge.  While it would be more efficient (as one suggests) to simply burn hydrogen in a spark ignition engine, it's considerably more efficient to use a fuel cell, as is being trialled in an 08 at the Severn Valley Railway.

 

If they're going to make a genuine steam loco though, I hope they improve the aerodynamics of the cabs and try to exceed 126mph........

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I understand that the Chief Engineer required that they be confined to the two major yards for which they were designed. On that basis, a standard radial tank was a better proposition, with wider availability. I can't imagine that there was much difference in the weight, so presumably it was the fixed wheelbase that caused the problem.

Best wishes 

Eric 

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Just a couple of (maybe) plausible concepts for slightly altered variants or evolutions of existing locomotives; supposing the L.M.S. took 'Big Bertha' out of traffic earlier than expected, and went for something more akin to the 8F to replace it, here's a heavily altered 0-10-0 variant with a slightly enlarged firebox to go with.

 

A long with that, a quick render of a 'modernised' A1/A1X, complete with extended tanks and Bulleid-style boxpok wheels to compensate for the extra weight.

 

Would either of these have served much of a purpose? I doubt it, but it's nice to let Rule 1 have its way sometimes.

Screenshot 2024-07-31 10.03.39 AM.png

Screenshot 2024-07-31 10.07.50 AM.png

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21 minutes ago, KnightOnASkateboard said:

Just a couple of (maybe) plausible concepts for slightly altered variants or evolutions of existing locomotives; supposing the L.M.S. took 'Big Bertha' out of traffic earlier than expected, and went for something more akin to the 8F to replace it, here's a heavily altered 0-10-0 variant with a slightly enlarged firebox to go with.

 

But such tiny cylinders - even if one supposes there are inside cylinders too. Big Bertha's four cylinders were 16 3⁄4 in diameter × 28 in stroke. Added to which, how is the steam getting to the cylinders in your picture? 

 

Big Bertha ran as many miles tender first as it did chimney first, hence the cut-down sides to the coal space, to give the enginemen a clear view. How clear a view do the enginemen have in your design? I note you have at least given them the tender cab!

 

Making these mock-ups is a good way of learning why real locomotives looked the way they did!

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4 hours ago, KnightOnASkateboard said:

Would either of these have served much of a purpose? I doubt it, but it's nice to let Rule 1 have its way sometimes.

 

Forgive me for failing to say: an interesting first post and welcome to the forum! Looking forward to many more posts.

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3 hours ago, Compound2632 said:

 

But such tiny cylinders - even if one supposes there are inside cylinders too. Big Bertha's four cylinders were 16 3⁄4 in diameter × 28 in stroke. Added to which, how is the steam getting to the cylinders in your picture? 

 

Big Bertha ran as many miles tender first as it did chimney first, hence the cut-down sides to the coal space, to give the enginemen a clear view. How clear a view do the enginemen have in your design? I note you have at least given them the tender cab!

Greatly appreciate the feedback on that one; I've attached a second draft with some beefier cylinders and other alterations. I've adopted a larger dual chimney, and as for the tender, I've gone with the option of a slight extension in exchange for overall height. I'm still debating whether it would be more effective to have four cylinders of approx. 16 in diameter x 30 in stroke, or three of 18 in diameter and identical stroke. Any thoughts?

Screenshot 2024-07-31 2.08.23 PM.png

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In re your modernized Terrier, adding weight kind-of eliminates what made the Terriers so long lived.   Terriers were one of the few classes that could get to Wight without destroying the bridge.   Any modernization or replacement would have needed to match or exceed the power at the same weight.   

 

If you're looking at a Bulleid program, I'd wager he would have tried a DMU or up-geared and lightened version of his 0-6-0 shunters.   

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1 minute ago, KnightOnASkateboard said:

 I'm still debating whether it would be more effective to have four cylinders of approx. 16 in diameter x 30 in stroke, or three of 18 in diameter and identical stroke. Any thoughts?

 

Big Bertha had the second axle cranked to clear the connecting rods for the inside cylinders, so just having one inside cylinder would result in the simplification of only one crank to that axle, as well as only one crank on the driven axle. On the other hand, each set of outside Walschaerts valve gear drove the valves on two cylinders; a three-cylinder layout would need a third set of Walschaerts gear between the frames (as for a Royal Scot, Patriot, or Jubilee) or conjugated gear - in either case, an additional complication.

 

Your whole loco looks more convincing now - it has something of the air of those big American switchers.

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1 hour ago, AlfaZagato said:

In re your modernized Terrier, adding weight kind-of eliminates what made the Terriers so long lived.   Terriers were one of the few classes that could get to Wight without destroying the bridge.   Any modernization or replacement would have needed to match or exceed the power at the same weight.   

 

If you're looking at a Bulleid program, I'd wager he would have tried a DMU or up-geared and lightened version of his 0-6-0 shunters.   

I did have a small SR-style tank sitting somewhere in my files which might be more suited to the Wight role than the modernised Terrier; what do you make of it?

Screenshot 2024-07-31 3.31.57 PM.png

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If we are talking of the Lickey why does the engine need a big tender?  always water and coal at Bromsgrove and with a big tender more weight to drag up the hill. It may not even need a bigger firebox an 8f could take a lot of stick before things got trickey! And that well known phrase "mortgage the boiler" springs to mind. It does not need to be full at the top because the run back down is the place to top the boiler up.  Three cylinders three sets of valve gear, inside cylinder on its side. Are we good to go? more noise than a Jubilee!

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2 hours ago, Mike 84C said:

If we are talking of the Lickey why does the engine need a big tender?  always water and coal at Bromsgrove and with a big tender more weight to drag up the hill. It may not even need a bigger firebox an 8f could take a lot of stick before things got trickey! And that well known phrase "mortgage the boiler" springs to mind. It does not need to be full at the top because the run back down is the place to top the boiler up.  Three cylinders three sets of valve gear, inside cylinder on its side. Are we good to go? more noise than a Jubilee!

 

An Ivatt 2mt tender might work in those circumstances, even on an 8F, or 9F.

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4 hours ago, KnightOnASkateboard said:

I did have a small SR-style tank sitting somewhere in my files which might be more suited to the Wight role than the modernised Terrier; what do you make of it?

Screenshot 2024-07-31 3.31.57 PM.png

 

Are you sure that wasn't built at Stratford?

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The final evolution of the 'Big Bertha' successor, 2291 'Black Knight'. The enlarged firebox has been removed as per Mike's insight, and the tender has been adjusted to a more 2MT-style layout (my thanks to Melmoth for the suggestion). Just for fun, it's been granted a 'monochrome' livery to match its nameplates.

Screenshot 2024-07-31 11.36.57 PM.png

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19 hours ago, KnightOnASkateboard said:

I've adopted a larger dual chimney

As often, I'm confused on this. Does 'Son of Big Bertha' actually need a stubby dual chimney? I thought these were to improve high speed blast-induced drafting, and to lift the smoke higher above maximum-diameter boilers at speed, not for 15-25 mph shoving trains up the Lickey from behind.  As such, single or double, I'd have expected the chimney to be at the maximum allowed by the loading gauge to clear the smoke.

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