Unnecessary Steam Classes

Status
Not open for further replies.

matacaster

Member
Joined
19 Jan 2013
Messages
1,107
There were an enormous number of steam classes. Were chief mechanical engineers guilty of unnecessary developments of non-standard classes with minor wheel diameter differences, wheel arrangements. It sometimes looks like every little route nedded it's own design of locomotives. Why were the CMEs allowed to get away with this?
 
Sponsor Post - registered members do not see these adverts; click here to register, or click here to log in
R

RailUK Forums

hexagon789

Veteran Member
Joined
2 Sep 2016
Messages
12,016
Location
Glasgow
There were an enormous number of steam classes. Were chief mechanical engineers guilty of unnecessary developments of non-standard classes with minor wheel diameter differences, wheel arrangements. It sometimes looks like every little route nedded it's own design of locomotives. Why were the CMEs allowed to get away with this?
Arguably the 'Kings' of the GWR were an example of this. They had larger wheels and certain other modifications really as a PR exercise so the GWR could claim a 40,000lbs tractive effort. For their extra weight and tractive effort the Castles proved more capable of a good turn of speed as well as of course being less route restricted.
 

Spartacus

Established Member
Joined
25 Aug 2009
Messages
2,114
I’d certainly say some of the small numbered BR Standards were unnecessary, particularly the 2MT 2-6-2T which was practically a ‘copy and paste’ Ivatt.

It’s easy to view some of the small specialist classes as a waste now, but then standardisation was really in it’s early days, and building a new class, or variant of a class, would entail very little more effort than producing more of an existing class, and would usually incorporate improvements since the earlier design to improve efficiency or ease of maintenance, that might have been harder to implement on an existing class. Often the major components, like the boiler or wheels, would be shared by numerous designs anyway.
The new small classes could sometimes include small almost experimental devices, which were intended for later more important classes.
 

6Gman

Established Member
Joined
1 May 2012
Messages
7,131
There were an enormous number of steam classes. Were chief mechanical engineers guilty of unnecessary developments of non-standard classes with minor wheel diameter differences, wheel arrangements. It sometimes looks like every little route nedded it's own design of locomotives. Why were the CMEs allowed to get away with this?
Can you offer some examples?
 

LSWR Cavalier

Established Member
Joined
23 Aug 2020
Messages
1,230
Location
Leafy Suburbia
I think the Merchant Navies were like the Kings, big powerful engines but just too heavy, perhaps publicity and prestige were involved. The light pacifics were much more useful and had much better route availability
 

Bevan Price

Established Member
Joined
22 Apr 2010
Messages
5,851
I’d certainly say some of the small numbered BR Standards were unnecessary, particularly the 2MT 2-6-2T which was practically a ‘copy and paste’ Ivatt.

It’s easy to view some of the small specialist classes as a waste now, but then standardisation was really in it’s early days, and building a new class, or variant of a class, would entail very little more effort than producing more of an existing class, and would usually incorporate improvements since the earlier design to improve efficiency or ease of maintenance, that might have been harder to implement on an existing class. Often the major components, like the boiler or wheels, would be shared by numerous designs anyway.
The new small classes could sometimes include small almost experimental devices, which were intended for later more important classes.
I tend to agree about the BR Standards; the BR 2MT 2-6-0 was a near clone of the Ivatt LMS version. And some might wonder if they needed both 4-6-0s (75xxx) and 2-6-0 (76xxx) versions of 4MT locos.

Pre-BR, and pre-1923 Grouping, each railway had its own engineers, each with their own ideas. If more powerful locos were needed, they often "improved" or enlarged their previous designs -- although as history records, sometimes the changes proved to be "negative improvements", and it was necessary to introduce even more designs to do the required work. (e.g. LSWR, L&YR had some very good 4-4-0s for the time they were built, but early attempts to produce efficient, reliable 4-6-0s were unsatisfactory.)
 

Richard Scott

Established Member
Joined
13 Dec 2018
Messages
2,622
Arguably the 'Kings' of the GWR were an example of this. They had larger wheels and certain other modifications really as a PR exercise so the GWR could claim a 40,000lbs tractive effort. For their extra weight and tractive effort the Castles proved more capable of a good turn of speed as well as of course being less route restricted.
Kings actually had slightly smaller wheels, which allowed them to claim the hallowed 40,000lbs of tractive effort. Agree Castles probably a better prospect. Kings were just a glory class.
 

hexagon789

Veteran Member
Joined
2 Sep 2016
Messages
12,016
Location
Glasgow
Kings actually had slightly smaller wheels, which allowed them to claim the hallowed 40,000lbs of tractive effort. Agree Castles probably a better prospect. Kings were just a glory class.
Not really a steam man and not GWR either, so it stood to reason I'd get something wrong! So smaller driving wheels not larger to get the 'magic' 40,000?
 

Richard Scott

Established Member
Joined
13 Dec 2018
Messages
2,622
Not really a steam man and not GWR either, so it stood to reason I'd get something wrong! So smaller driving wheels not larger to get the 'magic' 40,000?
Correct, not sure of exact size but were slightly smaller and non standard size. Unusual for GWR, which actually seemed to have a lot of standardised parts.
 

Taunton

Established Member
Joined
1 Aug 2013
Messages
6,694
Kings actually had slightly smaller wheels, which allowed them to claim the hallowed 40,000lbs of tractive effort. Agree Castles probably a better prospect. Kings were just a glory class.
A King was very substantially more powerful than a Castle. The wheel size change didn't contribute that much, far more was the higher pressure boiler. Once they got on the line crews regarded them as about the biggest advance they had known since Churchward moved things on from 4-4-0s to the Star 4-cylinder 4-6-0.

Collett had more than one variance with wheels, the 81xx tanks were likewise a 61xx with the same 2 inches off the diameter. A dimension incidentally that can be lost just by wear on the tyres. The 61xx were great and powerful locos for their size (we had a few sent to Taunton when the London suburban trains were dieselised), the 81xx must have packed even more of a punch. I do believe that Collett (it would actually be his chief draughtsman) was looking more at improving acceleration with heavy trains and giving as much as they could on the South Devon banks than the old story about scoring with tractive effort numbers, and it may have been an attempt to knock bits off their axle weight, that had led to yet another standoff between the CME and his Civils colleague. Certainly the Kings would have been appropriate for the longest and heaviest GWR services, which were always the South Wales trains, but the civils would not do the work to allow them.
 

Cowley

Forum Staff
Staff Member
Global Moderator
Joined
15 Apr 2016
Messages
11,445
Location
Devon
A King was very substantially more powerful than a Castle. The wheel size change didn't contribute that much, far more was the higher pressure boiler. Once they got on the line crews regarded them as about the biggest advance they had known since Churchward moved things on from 4-4-0s to the Star 4-cylinder 4-6-0.

Collett had more than one variance with wheels, the 81xx tanks were likewise a 61xx with the same 2 inches off the diameter. A dimension incidentally that can be lost just by wear on the tyres. The 61xx were great and powerful locos for their size (we had a few sent to Taunton when the London suburban trains were dieselised), the 81xx must have packed even more of a punch. I do believe that Collett (it would actually be his chief draughtsman) was looking more at improving acceleration with heavy trains and giving as much as they could on the South Devon banks than the old story about scoring with tractive effort numbers, and it may have been an attempt to knock bits off their axle weight, that had led to yet another standoff between the CME and his Civils colleague. Certainly the Kings would have been appropriate for the longest and heaviest GWR services, which were always the South Wales trains, but the civils would not do the work to allow them.

Absolutely. It’s worth taking a few minutes to see some of the YouTube clips of 6024 taking various banks around the network when it was still out and about...


The way a King sits back on its 4-6-0 chassis with that massive boiler and just digs in to the climb is a wonderful thing to behold.
Deeply impressive machines in my opinion.
 

Richard Scott

Established Member
Joined
13 Dec 2018
Messages
2,622
Absolutely. It’s worth taking a few minutes to see some of the YouTube clips of 6024 taking various banks around the network when it was still out and about...


The way a King sits back on its 4-6-0 chassis with that massive boiler and just digs in to the climb is a wonderful thing to behold.
Deeply impressive machines in my opinion.
No doubt they were impressive, will bow to others superior knowledge on them! Did have a ride on footplate and a drive of 6023 a couple of years back, certainly one that was ticked off bucket list.
 

Cowley

Forum Staff
Staff Member
Global Moderator
Joined
15 Apr 2016
Messages
11,445
Location
Devon
No doubt they were impressive, will bow to others superior knowledge on them! Did have a ride on footplate and a drive of 6023 a couple of years back, certainly one that was ticked off bucket list.

You lucky ****! :lol:
 

Richard Scott

Established Member
Joined
13 Dec 2018
Messages
2,622
You lucky ****! :lol:
I must admit that was good! Not a massive steam fanatic but a few out there on bucket list. Managed to tick off an unrebuilt Bulleid in form of 34092 a few years back. If can get a Britannia will really be happy!! Sorry going off topic in some self indulgence there!!
 

Taunton

Established Member
Joined
1 Aug 2013
Messages
6,694
6023 King Edward II said:
If I'd known you were going to laugh at my driving wheels, well, I'd never have allowed you up onto my footplate ...
 

Irascible

Member
Joined
21 Apr 2020
Messages
875
Location
South-West
This ( the original topic, not Kings ) was something I thought about after the last modernisation plan thread: why did we need all the standard classes rather than every other one? and so on. I'll assume there are bigger economies in matching steam to duties than diesels, and there were an awful lot more places to go too, but where did this idea of proliferation come from?

The GWR did make a good go of standardisation - there were a lot of class numbers but they built basically the same classes for decades. Autotank ( that is an ancient design ), Small & large panniers & prairie tanks, a small light tender engine ( 43xx, Manor ), mid size with choice of gearing effectively, express, and heavy haul. There were some small specialists ( Kings, express goods etc ) but mostly they were the same classes from the same interchangeable parts kit Churchward put together & still built by BR. Stanier was a GWR man ( close to being CME ) & did the same thing.

Pretty sure the MN were needed - what else was going to handle heavy trains? double heading is not something to schedule if possible.
 

daveinstoke

Member
Joined
11 Dec 2020
Messages
33
Location
Burslem
plus the railways were all pretty worn out after the war. A lot of older loco's, as we all know were scrapped.
 

edwin_m

Veteran Member
Joined
21 Apr 2013
Messages
21,802
Location
Nottingham
I tend to agree about the BR Standards; the BR 2MT 2-6-0 was a near clone of the Ivatt LMS version.
On the other hand, if more of a particular type was necessary there's an argument for tweaking an existing design to use standard components, rather than perpetuating the holding of multiple sets of spare parts etc or starting from scratch with something to do exactly the same job.

To me the more significant question is whether there was a need for that many 2-6-0Ts in the first place - certainly with hindsight the loss of local goods and the closure or dieselisation of local passenger would suggest there wasn't.
 

Peter C

Established Member
Joined
13 Oct 2018
Messages
4,105
Location
GWR land
If we're looking for unnecessary classes (although I must admit my example is a class of one), then surely the GWR's 'The Great Bear' Pacific of 1908 would be a good contender? It never worked as well as hoped, and the demand for such a large locomotive just wasn't around when it was built. The 'Stars' worked perfectly fine from what I've read.

Why were the CMEs allowed to get away with this?
In the case of the aforementioned Pacific, the reasoning isn't clear but it's thought that Churchward may have designed the engine following pressure from the GWR publicity dept. to make the largest and most powerful engine in the UK at the time. I expect the case may be that various CMEs were always trying to find the best/cheapest/most economical ways of improving the performance of their designs?

-Peter
 

Taunton

Established Member
Joined
1 Aug 2013
Messages
6,694
In the case of the aforementioned Pacific, the reasoning isn't clear but it's thought that Churchward may have designed the engine following pressure from the GWR publicity dept.
Churchward built a large number of different prototypes in his early days, all with different combinations of elements. Mostly numbered either side of 100 (like the Great Bear, which was No 111), they embraced tank locos, various tender locos, etc. The GWR had the money for these various trials, which fundamentally set the style for everything that followed until diesels came along.

Churchward found, probably not to his surprise, that a loco with a trailing carrying axle didn't work well in maximising power transmission. The three 4-4-2 Atlantics had sort of shown him the way in this; they were rebuilt a lot faster than No 111 was. Plus the old running sore of the feud between CME Churchward and Chief Civil Engineer Grierson came up yet again over such a large locomotive, giving it very limited route availability. Churchward had hacked off Grierson in the early 1900s when, as one of the many GWR new routes of that era, the civils had designed a new express route between Exeter and Plymouth to overcome the South Devon banks (plus, incidentally, the Dawlish seas - sound familiar?), and it was going to be the next big project. Churchward told the GWR directors he could design a loco to handle expresses up the banks for a fraction of the cost, the directors were convinced, and the two hardly spoke again.
 
Last edited:

Peter C

Established Member
Joined
13 Oct 2018
Messages
4,105
Location
GWR land
Churchward built a large number of different prototypes in his early days, all with different combinations of elements. Mostly numbered either side of 100 (like the Great Bear, which was No 111), they embraced tank locos, various tender locos, etc. The GWR had the money for these various trials, which fundamentally set the style for everything that followed until diesels came along.
I didn't know that - thanks for explaining. That makes sense as the GWR were well-known for liking standardisation so they'd have wanted to test and test to find the best class possible.

Churchward found, probably not to his surprise, that a loco with a trailing carrying axle didn't work well in maximising power transmission. The three 4-4-2 Atlantics had sort of shown him the way in this; they were rebuilt a lot faster than No 111 was.
Again - very interesting. I think the GWR did quite a bit of rebuilding - or have I got that completely wrong?

-Peter
 

Dr Hoo

Established Member
Joined
10 Nov 2015
Messages
2,747
Location
Hope Valley
At the most general level I have often reflected on just how 'bespoke' the rag bag of railway routes was many years ago. Various routes perhaps had very lightly laid track, tight loading gauge, sharp curves, punishingly steep gradients (with issues for both traction going up and braking coming down), smoke problems in tunnels, some areas remote from sources of good coal at affordable prices and so on. So 'standard' designs often just couldn't fit or work, or else were very 'difficult' or inefficient if they could go there.

So there would a constant demand from the operating and civil engineering functions for specific designs with shorter fixed wheelbases, more power, better acceleration, lighter weight, more water capacity, ability to burn 'slack' coal or whatever.

From another angle, in the absence of computer modelling and design, and general 'mass production' it was actually very hard to know exactly how any new design would work out in practice. Hence the 'let's tweak the boiler pressure/diameter, wheel sizes, piston stroke, valve gear, etc.' syndrome to see if it gave better results.
 

Irascible

Member
Joined
21 Apr 2020
Messages
875
Location
South-West
I didn't know that - thanks for explaining. That makes sense as the GWR were well-known for liking standardisation so they'd have wanted to test and test to find the best class possible.

Again - very interesting. I think the GWR did quite a bit of rebuilding - or have I got that completely wrong?

-Peter

Of inherited classes, mostly - the GWR did very little innovation ( in steam ) post Churchward until Hawksworth's Counties & they didn't really need to rebuild ( reuse bits, certainly ), which says a fair bit about how good the Churchward classes were. If you want the evolution of GWR steam, look at the LMS.

Would be interesting to know how much operations modelling was done in the early c20, proliferation does tend to indicate decentralised decision making a bit.
 

Peter C

Established Member
Joined
13 Oct 2018
Messages
4,105
Location
GWR land
Of inherited classes, mostly - the GWR did very little innovation ( in steam ) post Churchward until Hawksworth's Counties & they didn't really need to rebuild ( reuse bits, certainly ), which says a fair bit about how good the Churchward classes were. If you want the evolution of GWR steam, look at the LMS.
Interesting. That definitely seems to prove that Churchward's designs were pretty good at doing what they were designed to do. I suppose the GWR, therefore, would have one of the smallest numbers of 'unnecessary' steam classes; they standardised on a number of designs using standardised parts?

-Peter
 

edwin_m

Veteran Member
Joined
21 Apr 2013
Messages
21,802
Location
Nottingham
Interesting. That definitely seems to prove that Churchward's designs were pretty good at doing what they were designed to do. I suppose the GWR, therefore, would have one of the smallest numbers of 'unnecessary' steam classes; they standardised on a number of designs using standardised parts?
It might have allowed them to produce even more different classes by combining their standard parts in slightly different ways...
 

Peter C

Established Member
Joined
13 Oct 2018
Messages
4,105
Location
GWR land
It might have allowed them to produce even more different classes by combining their standard parts in slightly different ways...
Now that's a good point, and it leaves me wondering how many different such combinations there could have been... ;)

-Peter
 

Bevan Price

Established Member
Joined
22 Apr 2010
Messages
5,851
Now that's a good point, and it leaves me wondering how many different such combinations there could have been... ;)

-Peter
I can envisage a King or Castle boiler being put on a 2-8-0 chassis to produce a heavy freight loco -- but whilst able to haul more than a 28xx Class 2-8-0, such freights would have been too long for many sidings & freight loops. Also, like the 47xx Class 2-8-0s, the civil engineers would have severely limited their route availability.
 

edwin_m

Veteran Member
Joined
21 Apr 2013
Messages
21,802
Location
Nottingham
I can envisage a King or Castle boiler being put on a 2-8-0 chassis to produce a heavy freight loco -- but whilst able to haul more than a 28xx Class 2-8-0, such freights would have been too long for many sidings & freight loops. Also, like the 47xx Class 2-8-0s, the civil engineers would have severely limited their route availability.
That's pretty much what Stanier did I think - 8F, Black 5 and Jubilee were the same boiler sitting on different wheel arrangements.
 

Irascible

Member
Joined
21 Apr 2020
Messages
875
Location
South-West
That's pretty much what Stanier did I think - 8F, Black 5 and Jubilee were the same boiler sitting on different wheel arrangements.

GWR too - 2800s, Saints, Halls, Grange all used the same boiler. 4300s, big prairie tanks, 4200 tanks, Churchward's Counties all shared the same boiler also. I don't remember but I suspect they shared cylinders too. Churchward wanted to put the boiler from the 4700s on the Castle chassis but it'd have been too heavy.
 
Status
Not open for further replies.

Top