The rise of the 4-6-0 and why were there none on the GNR

[Wainwright]

The SECR 'K's had baffles, iirc... But it was an issue.
The LNER and its constituents, by contrast, never developed a genuine large,fast tank engine (the Raven 4-4-4T, Robinson 4-6-2T and the V1/V3 being the nearest things, but none of them really were for secondary mainline usage like the SECR 2-6-4Ts and Brighton 4-6-4Ts, or the LMS inherited 4-6-4Ts on the LYR and G&SWR) - the proposed Southend tank would probably have been the only try.

It may seem strange to keep referring to the Southern in an LNER thread, but there were a lot of connections between the design teams particularly in the 20s - these trials, and the development of the Gresley and Holcroft motions being cases in point...

[Hatfield Shed]

I believe that the end conclusion was that there was nothing significantly wrong with the K tanks - the water in boilers, tender tanks and loco tanks inevitably sloshed about in all classes of steam loco - but that given the tramway's often poor track condition, running a large tank loco at speed was probably inadvisable.

Cannot remember what film it is in, but I have seen water rythmically sloshing out of the tender filler cap of a BR liveried A4 running at full chat; presumably just off the troughs, and so well filled. There's vastly superior analytical technique for modelling the effects of unconstrained fluids in moving vehicles now, ship architects ran into this trouble big time when oil tankers were developed, and it remains a major problem for open deck ferries; and as for the discovery of what large partly filled fuel tanks could mean for aviation, the crashes were spectacular.

[earlswood nob]

A note about the LBSCR Baltic tanks;

Billinton originally planned to build a 4-6-0 as well and compare them. However, the 4-6-0 order was converted into another 4-6-4T.

The Baltics was a little unstable at speed and the top of the tanks were blanked off, and a well tank added, which lowered the centre of gravity.

They then became good riders, but were converted to 4-6-0s after they became redundant with the Brighton electrification.

Earlswood nob

[Mickey]

A note about the LBSCR Baltic tanks;

Billinton originally planned to build a 4-6-0 as well and compare them. However, the 4-6-0 order was converted into another 4-6-4T.

The Baltics was a little unstable at speed and the top of the tanks were blanked off, and a well tank added, which lowered the centre of gravity.

They then became good riders, but were converted to 4-6-0s after they became redundant with the Brighton electrification.

A name thats been cropping up a fair bit lately (with me) Billinton onetime Locomotive Superintendent of the Liver Bacon & Sausage Company and I must admit i've developed a liking for his 0-6-2 E4 tanks they had lovely straight lines which were strangely very pleasing on the eye I find.

Mickey

[Wainwright]

Ah, you're thinking of Robert John Billinton, the father (in charge of locos on the LBSC1890-1904) - some allege the 0-6-2Ts to be based on Stroudley's work also...

Lawson Boskovsky (his mother was Polish) was Locomotive Engineer 1912-1923 and did the 4-6-4Ts (also being the designer of Thomas the Tank Engine, ie the E2 0-6-0T.

In between came Douglas Earle Marsh, trained under Ivatt, and somewhat erratic in the utility of his designs.

[Mickey]

I must admit Wainwright the locomotive side of railways isn't my specialist subject although regardless of a locos performance if it looks good (to me) I like it which means when it comes to british locos I virtually like them all!!.

Back in the early 1990s I started reading quite a bit about british locomotive engineers and didn't realise how many there were, most people have heard of Gresley, Stanier, Churchward & Bulleid but there was several hundred more that rarely get a mention these days.

Mickey

[Hatfield Shed]

I...when it comes to british locos I virtually like them all!...

If you are of a sensitive disposition, first put on your thickest beer goggles. Then google 'Kruger locomotive GWR'.

There's a bit at the front that looks slightly like Stratford's S69, so that's alright. It's a thoroughbred Frankenstein's monster after that though.

...Lawson Boskovsky ...

So that's where Huxley got that from, never made the connection before. (Brave New World - recommended to any who have not encountered it - closer to present realities than many would care to admit.)

[Mickey]

I...when it comes to british locos I virtually like them all!...

If you are of a sensitive disposition, first put on your thickest beer goggles. Then google 'Kruger locomotive GWR'.

There's a bit at the front that looks slightly like Stratford's S69, so that's alright. It's a thoroughbred Frankenstein's monster after that though.

Yeah good one Hatfield Shed I had actually seen 'it' before years ago when I was reading about William Dean Locomotive Superintendent of the Great Western Railway (1877-1902) and yes it was bit of a 'ugly duckling' alright although I believe William Dean was a good locomotive engineer to the Great Western Railway during his time as there locomotive superintendent at Swindon also I believe to George Jackson Churchwards credit (Churchward superseded Dean as the Great Western Railways locomotive superintendent in 1902 and he had also worked under William Dean at Swindon) Churchward gave part credit to Dean for the design of the Great Western Railways first 4-6-0 loco of the 2-cylinder 'Saint class' appearing in 1902, a nice loco with nice classic british lines.

Mickey

[Wainwright]

Moving more specifically back to 4-6-0s and particularly back to mixed-traffic ones, it occurs to me that a possibly overlooked reason the LNER (rather than the GNR) didn't build them may be that they were in fact surprisingly ahead of almost all other UK railways in this regard through what they inherited from the NER and NBR.

- The B5s, B6s and B7s and the B15s and B16s were some of the best of this wheel format and type available in the UK, and they were (in 1923) pretty modern, too.

- By contrast, the LMS only had the LNWR 19" Goods (a turn-of-the-century type), and a variety of discarded passenger locos, or the various small (in number) classes turned out by Scottish railways for upland passenger work, of which they perpetuated only the Caledonian 60 class 'greybacks', which have a bad rep with almost everyone I've read. They built Horwich Crab 2-6-0s instead (and the Stanier successors) until well into the 30s.

- The GWR (as mentioned previously) didn't build a single mixed-traffic 4-6-0 until 1924. OK, they then produced a classic and built tons of them, but they were playing catch-up, owing to their previous reliance on 2-6-0s and 2-8-0s.

- OK, the Southern did build more of the LSWR H15s and S15s, but Urie's design did require nobbling by Maunsell. And in power terms they were behind the LNER's locos, I'm pretty sure (Oh, just checked that - only just, comparing the S15 and B16). And the varying nature of their track and routes prevented them using them across their system. 2-6-0s were always needed, again.

Maybe, maybe if the LNER's design team had had a different attitude, and not pursued the K3, then developed it into the 2-6-2 (owing to their dalliance with boosters, as also tried out on Raven Atlantics) they would have arrived at the B16/2 earlier, 'standardised' it and built more (or a smaller-wheeled version of the B17s and B12s, I suppose).

But what I'm trying to say, is, maybe there wasn't the sense of historical inevitability about the mixed traffic 4-6-0 that there is with hindsight, particularly after the Black 5.

If we divide the 'peacetime' Grouping period into 2 eras, 1923-1931 and 1931-1940, it's only in the 1930s that Gresley's choices start to look eccentric. Up to the early 30s, an observer would not have found the absence of new mixed-traffic 4-6-0s on the LNER odd at all.

[Hatfield Shed]

I'd turn that round, as there is nothing remotely 'inevitable' about the 4-6-0, and by the 1940s it was clearly showing its limitations in power production. The telling marker for this: Riddles maximum power 4-6-0 was a class 5, everything bigger got a wide firebox, to the tune of 30% of his build.

It was never essential for the LNER, which had a design inheritance that made the wide firebox type with a rear carrying axle the norm for maximum power types, and could have gone to the end with secondary steam power in the 2-6-0 format. Comparison with other centres of steam loco development will suggest that the UK railway's over-reliance on the 4-6-0 was an aberration.

[Pebbles]

I do wonder where all this discussion rests with the almost 4,000 P8s produced. When it comes to narrow fireboxes, Chapelon appears to have been very successful in their application and indeed converted types with wide fireboxes to narrow fireboxes. When it comes to the adoption of the 4-6-0 by the LNER I suggest that the growing dominance of Doncaster design philosophy sidelined the configuration, although Thompson made a good fist of the B12/3. Elsewhere I have made the point that the Gresley conjugated arrangement was more amenable to a leading pony truck than a bogie thus the logical use of 2-6-0 and 2-6-2 configurations. In the case of the LNER once higher boiler pressures were accepted enabling two cylinders could do the job a lengthened K2 with a leading bogie was always a possible way forward. Engineers are people of their times and often retrospective analysis fails to address, and appreciate, the constraints they had to work within.

[Wainwright]

Pebbles,

The P8 sounds a redoubtable loco, but the combination of 170 psi, 24" cylinders and massive standardisation on not one, but two highly centralised and organised railway networks (first Prussia, then, from 1920, the new national German system) seems unachievable for several reasons from a British perspective (not least of which is loading gauge).

And, again, it's a passenger type cascaded to mixed-traffic usage.

The post-WWII successor Class 23 seems very B1esque, with its 230psi, though.

[Wainwright]

And Robert Garbe (designer of the P8) sounds like he would have been revered on the LMS. Extremely pragmatic, obsessed with economy and simplicity, basically a maker of 'idiot-proof', infinitely-repeatable designs using but never over-extending the then-modern technology (which isn't to disparage him, there's a hell of a talent to that).

In some respects, as near a polar opposite of Gresley (and certainly Bulleid) as one could get.

[Pebbles]

As far as I can see the points at issue were the continental adoption of the 4-6-0 configuration and narrow firebox. The P8s were in many respects ahead of their time and whether a comparable British engine could have been produced at that time within our restrictive loading gauge is debatable. The loading gauge issue does point to why 3 cylinders were eventually used, although advocates pointed to other benefits. One issue that I would be interested in knowing - and I assume that it had piston valves - is whether the P8 suffered problems of leaking valves that were experienced with British engines. Clearly in the early days of superheating wear and lubrication issues caused concern. This is all rather off the point, but I believe that the Class 23 was in fact a 2-6-2 with a wide firebox; taking us back to Gresley and Doncaster.

[Hatfield Shed]

The narrow firebox with a leading bogie, for a 4-4-0 and then a 4-6-0, is a 'natural' locomotive development path for an express and mixed traffic machine. While the coal quality is good, and the power demands modest it will perform well. But eventually with power demands rising and coal quality usually falling, it is a dead end, and the larger grate area required to increase power production demands the adoption of a wide firebox. It is that simple.

We should note that even Chapelon - who truly lurved the narrow firebox layout - had to abandon it when designing for highest power outputs