Imaginary Locomotives

[John Besley]

Imagine a Maunsell railcar, I've always thought a Nelson would make a great kit bashed Railcar 

 

If I was working in 4mm I'd have built one as a 2 car set by now 

[AlfaZagato]

I don't know about a Nelson-based railcar.   Maunsell wasn't really afraid of ICE, though.   I could see him approaching EE for a four-cylinder version of the six they loaded into his shunters.   I wonder is a useable genset could have been built small enough to fit under a carriage floor in the 30's.

[Corbs]

Or have it in between the passenger and driving compartments on one carriage.

[PhilJ W]

1 hour ago, AlfaZagato said:

I don't know about a Nelson-based railcar.   Maunsell wasn't really afraid of ICE, though.   I could see him approaching EE for a four-cylinder version of the six they loaded into his shunters.   I wonder is a useable genset could have been built small enough to fit under a carriage floor in the 30's.

Armstrong Whitworth built just such DEMU and it was placed in service by the LNER.

The engine generator unit was fitted under the floor.

 

Edited July 15, 2022 by PhilJ W

[John Besley]

13 hours ago, Corbs said:

Or have it in between the passenger and driving compartments on one carriage.

That's what I would have opted for but like an HST

[Bittern]

On 15/07/2022 at 04:52, tythatguy1312 said:

To continue discussion of them, a unique possibility that's dawned upon me is what could've happened if Peppercorn, Ivatt, Bulleid or Collett had been trusted with the job of designing the BR Standard range instead of Riddles. There could be some truly fascinating potential here.

The other fun idea that the argument about Thompson raises is "What if Maunsell had lasted a bit longer on the Southern and Bulleid became CME of the LNER?"

 

As for Bulleid standards, I'd expect gear-driven miniature valve gear like he wanted for the Spamcans, BFB wheels, a push for shed modernisation (which may or may not have happened, but could have reduced the pressure for the 1955 modernisation), casing designed to reduce cleaning effort, and an absurdly oversized bogie Sentinel. 

 

Ivatt standards would probably be very similar to the Riddles ones, except some of the stylistic touches, where I personally think Riddles's taste comes out ahead. On second thoughts though that could just be budget, so a non-austerity Ivatt design would be an interesting conjecture.

 

On 05/07/2022 at 05:17, tythatguy1312 said:

Alas, I'm unsure as to why someone would actively dislike Thompson for aesthetic issues, especially considering how the (admittedly somewhat ugly) BR Standard Class 9f is regularly cited as extremely popular.

The 9f has an internal consistency to its design (though I think the Standard 4 Tank is the most attractive), whereas Thompson's rebuilds look like they're cobbled together out of an ill-assorted set of parts without any thought to styling (because they were). OTOH, while the Springboks weren't as attractive as the B17s or V2s, they're still more decorative than, say, an Ivatt class 4.

 

(While I'm criticising LNER pacific aesthetics though, Peppercorn's front half was nothing to shout about and the A3s would have been tidier with the footplate in front of the splashers raised a couple of inches.)

[PhilJ W]

What if Gresley had lived and become CME instead of Riddles?

[Compound2632]

9 minutes ago, PhilJ W said:

What if Gresley had lived and become CME instead of Riddles?

 

He was 65 when he died in 1941. Stanier was the same age as Gresley. Bulleid had reached that age in 1947, Hawksworth in 1949. Riddles was 56 in 1948.

 

 

[Flying Fox 34F]

On 15/07/2022 at 07:55, rockershovel said:

One thing I have never quite worked out, is how the GWR managed to design a 4-6-0 with outside cylinders behind the leading truck and endow it with a quite majestic appearance, while the LNER's 4-6-2 variation on that theme simply looks misconceived. 

 

It can't just be the plate frames outside the leading axle...

It’s all down to the relevant Loading Gauge of each railway. The Castle class has outside cylinders over the rear bogie wheels, whereas, the Thompson Pacific’s had to have the cylinders behind the rear bogie wheels. The 4 cylinder versus 3 cylinder would have affected the design parameters as well.  Perhaps a 4 cylinder Thompson Pacific could have smaller diameter cylinders and a neater appearance. But remember there was a War On, at the time the later appeared.

 

Paul

[Flying Pig]

51 minutes ago, Flying Fox 34F said:

It’s all down to the relevant Loading Gauge of each railway. The Castle class has outside cylinders over the rear bogie wheels, whereas, the Thompson Pacific’s had to have the cylinders behind the rear bogie wheels. The 4 cylinder versus 3 cylinder would have affected the design parameters as well.  Perhaps a 4 cylinder Thompson Pacific could have smaller diameter cylinders and a neater appearance. But remember there was a War On, at the time the later appeared.

 

Paul

 

Was it not also a result of Thompson wanting to use equal length connecting rods with divided drive?

[rockershovel]

53 minutes ago, Flying Fox 34F said:

It’s all down to the relevant Loading Gauge of each railway. The Castle class has outside cylinders over the rear bogie wheels, whereas, the Thompson Pacific’s had to have the cylinders behind the rear bogie wheels. The 4 cylinder versus 3 cylinder would have affected the design parameters as well.  Perhaps a 4 cylinder Thompson Pacific could have smaller diameter cylinders and a neater appearance. But remember there was a War On, at the time the later appeared.

 

Paul

I'd rather suggest that the Kings were the ultimate Edwardian locomotive, the final flourish of an aesthetic which, like the 1920s racing Bentleys or the chrome tanks of a Brough Superior, set the trend and didn't have a wrong line anywhere.

 

The Thompson Pacifics belonged to a different aesthetic, that of the Gresley Pacifics and the magnificent 2-8-2 which was sui generis and peaked after a single generation. 

[lanchester]

On 15/07/2022 at 15:12, 62613 said:

I think the GNR changed to all- steel underframes and, on the gangwayed stock at least, Pullman gangways and buckeye couplers, when Gresley became C & W superintendent in 1906. He had a large interest in the ECJS stock as well, so the NER and NBR would have been building similar from then as well, surely?

 

Given the heat generated when anyone mentions Thompson, I'm a bit reticent about putting this forward - but wasn't Thompson Gresley's successor as C&W boss on the Great Northern? And, contrary to the notion we are sometimes offered, that ET was viscerally opposed to anything HNG, Great Northern (and ECJS) carriage development seems to have continued on an even, mildly progressive, keel (allowing of course for the Great War). ET's much later developments such as plywood body sheets were a WW2 necessity, and his tendency towards 1/3, 2/3 doors rather than at carriage ends, whilst not I imagine unique, certainly counts as progressive. 

 

Given the relative costs and performance of steel against iron, structural timber, or some combination - the thing surely is not that HNG went for all-steel underframes with Gresley (if that is indeed when and why they changed) but why did anyone not?

 

 

[62613]

19 hours ago, Flying Pig said:

 

Was it not also a result of Thompson wanting to use equal length connecting rods with divided drive?

One of the main reasons, IIRC

 

[62613]

15 hours ago, lanchester said:

Given the heat generated when anyone mentions Thompson, I'm a bit reticent about putting this forward - but wasn't Thompson Gresley's successor as C&W boss on the Great Northern? And, contrary to the notion we are sometimes offered, that ET was viscerally opposed to anything HNG, Great Northern (and ECJS) carriage development seems to have continued on an even, mildly progressive, keel (allowing of course for the Great War). ET's much later developments such as plywood body sheets were a WW2 necessity, and his tendency towards 1/3, 2/3 doors rather than at carriage ends, whilst not I imagine unique, certainly counts as progressive. 

 

Given the relative costs and performance of steel against iron, structural timber, or some combination - the thing surely is not that HNG went for all-steel underframes with Gresley (if that is indeed when and why they changed) but why did anyone not?

 

 

I think the railways were coming under increasing pressure from the MoT to improve the crashworthiness of passenger coaches as well. Thought that Thompson was disrict loco superintendent at Stratford in the 1930s; he was responsible for the rebuilds of the Clauds to D16/3, and the B12s to B12/3, wasn't he?

 

[billbedford]

19 hours ago, Flying Pig said:

 

Was it not also a result of Thompson wanting to use equal length connecting rods with divided drive?

 

Was this actually true, or did he use connecting rods for which the tooling already existed?

[Flying Pig]

12 minutes ago, billbedford said:

 

Was this actually true, or did he use connecting rods for which the tooling already existed?

 

According to the LNER Encyclopedia page on the A2/2 rebuild:

 

Quote

Existing parts would be used as much as possible, including the short outside connecting rods. This led to the outside cylinders being mounted relatively far back. The Gresley conjugated gear on the middle cylinder required a high level of maintenance, so Thompson replaced this with Walschaerts valve gear. For clearance, this meant the middle cylinder had to drive the leading driving axle.

 

...but why this scheme was used on the other Pacifics isn't clear.  Hopefully someone will have a mor detailed reference and can clarify.

[Flying Fox 34F]

23 hours ago, Flying Pig said:

 

Was it not also a result of Thompson wanting to use equal length connecting rods with divided drive?

I suspect the use of the original connecting rods was to keep the conversion costs down.  ET was probably struggling to justify the cost of new rods as part of the project.

I know a weight diagram exists of one proposal for the rebuilds. In fact it looks like an A3 with divided drive.  I’ve no idea if it formed part of the original proposal to convert the P2’s when the details were submitted to the LNER Board.

 

Paul

[Guest Simon A.C. Martin]

6 hours ago, Flying Pig said:

...but why this scheme was used on the other Pacifics isn't clear.  Hopefully someone will have a mor detailed reference and can clarify.

 

The point that should be understood was that in 1943-46, the equal length connecting rods setup with divided drive was proving to be a success with the P2 rebuilds, the A2/2s, and the A2/1 and A2/3 which followed this copied the successful setup. Great Northern (A1/1) was not the same, with her centre connecting rod longer than her outside ones, but more or less aping the overall approach set by the 6ft 2in classes in terms of cylinder placement and divided drive.

 

All of the Thompson Pacifics could be considered stop-gaps, given the limitations placed on their design, building and reuse of parts and drawings where possible. The drawing office relaxed their approach when they were allowed and in Thompson's last year in the job the final versions of the A1 and A2 Pacifics were being openly developed with divided drive and a more steeply inclined centre cylinder and connecting rod setup, pre-dating the rebuilt Bulleid Pacifics (which were similar bar having drive all onto one axle). Peppercorn finished this development and the production A1s and revised production A2s came out under his tenure.

 

If you have any questions, please feel free to direct them via PM to me here or by email to my editor/publisher at Strathwood.

[Guest Simon A.C. Martin]

3 hours ago, Flying Fox 34F said:

I suspect the use of the original connecting rods was to keep the conversion costs down.  ET was probably struggling to justify the cost of new rods as part of the project.

I know a weight diagram exists of one proposal for the rebuilds. In fact it looks like an A3 with divided drive.  I’ve no idea if it formed part of the original proposal to convert the P2’s when the details were submitted to the LNER Board.

 

Paul

 

You are correct Paul, part of it was indeed a manufacturing saving measure (the railways had to justify all expenditure . It was also partially about drawing office time; the three sets of walschaerts with equal length con rods reduced drawing office time too (at a premium due to the work necessary for the war office).

[Murican]

Before I post more, I just was wondering if rmweb would ever be able to restore the pictures from before the upgrade.

 

I'm just checking as a way to let you all know that I'm still here. Right now I'm brainstorming some ideas for rewriting my British steam ideas. Plus maybe some additional ideas for alternate locomotives here in the states.

[Murican]

Another question for my planned revisions of my BR Standard steam ideas.

 

What are some proposed ideas for 6-coupled tender locomotives? Like 2-6-2s, 4-6-0s  and 4-6-2s? Part of it was that I just wanted inspiration for when I post my ideas to alternatehistory.com as well.

Edited July 22, 2022 by Murican

[Compound2632]

4 hours ago, Murican said:

Another question for my planned revisions of my BR Standard steam ideas.

 

What are some proposed ideas for 6-coupled tender locomotives? Like 2-6-2s, 4-6-0s  and 4-6-2s? Part of it was that I just wanted inspiration for when I post my ideas to alternatehistory.com as well.

 

This thread, passim.

[tythatguy1312]

5 hours ago, Murican said:

Another question for my planned revisions of my BR Standard steam ideas.

 

What are some proposed ideas for 6-coupled tender locomotives? Like 2-6-2s, 4-6-0s  and 4-6-2s? Part of it was that I just wanted inspiration for when I post my ideas to alternatehistory.com as well.

Luckily all 4 flavours of 6 coupled mainline locos in the UK were built in the UK, though the only notable tender 2-6-2's were LNER built. A 2-6-2 BR Standard could've been good, but I'm not really surprised by the faith in 4-6-0's that BR went with. Honestly what intrigues me more is a 4-4-2 BR Standard, mostly as a fun thought.

[Murican]

2 hours ago, tythatguy1312 said:

Luckily all 4 flavours of 6 coupled mainline locos in the UK were built in the UK, though the only notable tender 2-6-2's were LNER built. A 2-6-2 BR Standard could've been good, but I'm not really surprised by the faith in 4-6-0's that BR went with. Honestly what intrigues me more is a 4-4-2 BR Standard, mostly as a fun thought.

I honestly agree. I thought of the 74XXX numbering being used by BR Standard 5 Atlantics that'd be used mainly in the Scottish Region due to the alternate oil crisis.

[The Johnster]

A Riddles Atlantic might be justified as a horse for light loads at high speeds, difficult to imagine on a railway whose blanket 75mph wartime speed limit was not lifted until 1953.  Based on the 5MT, a 4P with 7’ plus driving wheels, perhaps non-stop Paddinton-Oxford or KX/Liverpool St-Cambridge in an hour or so, 5-coach all-first or Pullman trains for university professors and others of that sort, but it was not until after the 1955 plan that the speeds would have been able to have been exploited, and the die was cast by then.  Maybe Glasgow-Edinburgh ‘Inter City’, non stop in half an hour. 

Edited July 22, 2022 by The Johnster