Imaginary Locomotives

[Gibbo675]

Hi Folks,

 

If the WCML was so short on class 8 power than what exactly was stopping them building a load more Princess Coronations to the same diagram as 46256/7 ? That would have been a continuation of practice and standard parts already available with a locomotive that was known to be plenty capable and reliable without the need for an unknown to be introduced. I can understand the reasons for not building the 4-6-4 and the 4-8-4 types as new turntables would have also been needed in a great many places which was an expense and trouble that was avoided. At the time the Royal Scots were busily being mostly scrapped and replaced under a ruse known as, "converted", along with lots of black fives, some with steel fireboxes and Caprotti gear.

If a step forward was required then why not steel fireboxes and Caprotti gear fitted to a new build Duchess as an experiment as with the black fives?

 

The would have been cheaper and easier than a complete new build and cheaper than building two class 5's for every class 8, but then such is politics.

 

Gibbo.

[Gibbo675]

1 minute ago, rockershovel said:

 

The incentive to rebuild a non-standard locomotive into another non-standard locomotive, without the incentive to make best use of expensive, perfectly serviceable components and with the original experiment which led to its construction, concluded with no useful outcome.... not there, is it? 

Hi Mr Shovel,

 

The boiler from 6202 ended up on 6203 and is the one currently carried by said locomotive.

 

Gibbo

[JimC]

2 hours ago, rockershovel said:

 

I can’t imagine that a locomotive was simply built, as an amusing diversion for bored drawing office staff and/or megalomaniac CMEs. That isn’t how things get done, in the real world. 

The real reason things get done may be different from the ones presented to the directors though. In my own career I saw large sums expended on what I saw as bees in bonnets, vanity projects or 'looks good on the CV" when I felt the money would have been far better spent on low profile developments which would have done much more to enhance the work of the organisation, but wouldn't have been nearly as exciting. 

 

 

Edited January 3, 2021 by JimC

[john new]

4 minutes ago, rockershovel said:

 

The incentive to rebuild a non-standard locomotive into another non-standard locomotive, without the incentive to make best use of expensive, perfectly serviceable components and with the original experiment which led to its construction, concluded with no useful outcome.... not there, is it? 

 

There was a lesson learnt but not made public until after it had left BR ownership and was being rebuilt. The lesson - check what is delivered is what was designed! Assuming my memory remains correct the biggest problem with 71000 was it was not built to the drawings in the firebox area and therefore did not get adequate fire draughting. The restoration team found and corrected the error and transformed the locomotive's performance. But was it already a known problem but hushed up?

 

Why that wasn't discovered during shake down testing, or if it was the discovery got covered up, may come out eventually in someone's diaries.  Clearly possibles include (1) the loco depot side didn't want the engine with its complicated rotary gear, they already had adequate LMS designs, so even though crews knew of the steaming problem their hierarchy  were happy to let 71000 fail to meet expectations and therefore defer the rest of the class, (b) it was known about but there was a lot of a**e covering and (c) all matched with the change in direction and the quicker than originally planned  end to steam traction anyway so why bother to fix and build more of them.

 

[john new]

2 minutes ago, JimC said:

The real reason things get done may be different from the ones presented to the directors though. In my own career I saw large sums expended on what I saw as bees in bonnets, vanity projects or 'looks good on the CV" when I felt the money would have been far better spent on low profile developments which would have done much more to enhance the work of the organisation. 

 

 

 

So true. 

[rodent279]

7 minutes ago, john new said:

 

There was a lesson learnt but not made public until after it had left BR ownership and was being rebuilt. The lesson - check what is delivered is what was designed! Assuming my memory remains correct the biggest problem with 71000 was it was not built to the drawings in the firebox area and therefore did not get adequate fire draughting. The restoration team found and corrected the error and transformed the locomotive's performance. But was it already a known problem but hushed up?

 

Why that wasn't discovered during shake down testing, or if it was the discovery got covered up, may come out eventually in someone's diaries.  Clearly possibles include (1) the loco depot side didn't want the engine with its complicated rotary gear, they already had adequate LMS designs, so even though crews knew of the steaming problem their hierarchy  were happy to let 71000 fail to meet expectations and therefore defer the rest of the class, (b) it was known about but there was a lot of a**e covering and (c) all matched with the change in direction and the quicker than originally planned  end to steam traction anyway so why bother to fix and build more of them.

 

That does beg the question that if the defect was known about, why was it not corrected? Is it major work and very expensive to alter the ashpan draughting arrangements?

[Gibbo675]

10 minutes ago, john new said:

 

There was a lesson learnt but not made public until after it had left BR ownership and was being rebuilt. The lesson - check what is delivered is what was designed! Assuming my memory remains correct the biggest problem with 71000 was it was not built to the drawings in the firebox area and therefore did not get adequate fire draughting. The restoration team found and corrected the error and transformed the locomotive's performance. But was it already a known problem but hushed up?

 

Why that wasn't discovered during shake down testing, or if it was the discovery got covered up, may come out eventually in someone's diaries.  Clearly possibles include (1) the loco depot side didn't want the engine with its complicated rotary gear, they already had adequate LMS designs, so even though crews knew of the steaming problem their hierarchy  were happy to let 71000 fail to meet expectations and therefore defer the rest of the class, (b) it was known about but there was a lot of a**e covering and (c) all matched with the change in direction and the quicker than originally planned  end to steam traction anyway so why bother to fix and build more of them.

 

 

1 minute ago, rodent279 said:

That does beg the question that if the defect was known about, why was it not corrected? Is it major work and very expensive to alter the ashpan draughting arrangements?

Hi Chaps,

 

My experience with Seventy One Million was that after the draughting arrangements to both the smoke box and the ashpan were rectified coupled to a new profile on the cams that slightly altered the the valve events all manner of trouble ensued. The boiler evaporated so much water that crown sheet effervescence was observed which cause both the crown sheet to become scorched several times, even with a correct water level shewing in the gauge glasses, the crown stay nuts to be burned off frequently causing damage to the crown stays also, scorching of the combustion chamber valley laps and the inner back head lap, along with the combined effect of thermic shock and cinder cutting to the tube and flue end beads all caused huge expense.

 

You don't get something for nothing. Should the DoG have had a steel firebox and thermic syphons as the Merchant Navy class did then it would have been able to cope with such a steaming rate as heat transfer and boiler water circulation would have allowed it.

 

Seventy One Million is a reference to the huge cost of repairs !

 

My view is that the Bullied pacifics should have been rebuilt with Caprotti gear instead of what was done to them., they would have been phenomenal locomotives.

 

Gibbo.

[rockershovel]

...the previous group of posts all seem to tend in the same direction... that the BR Standards were, for all practical purposes, robust and effective solutions to a category of locomotives which were well known to be approaching their end of service, were unlikely to undergo further radical transformation, would not be replaced or further developed and would not repay further development. 

 

The one about the boiler from 6202 seems to be a case of this, combined with "making best use of salvageable components" 

 

what is interesting, is the quote about Bulleid's Presidential Address to the Locomotive Engineers, which appears to state that the cost of electric locomotives was not substantially higher than steam, whereas diesel locomotives were much higher. It would be interesting to know more about this?

 

 

[melmerby]

3 hours ago, rockershovel said:

 

what is interesting, is the quote about Bulleid's Presidential Address to the Locomotive Engineers, which appears to state that the cost of electric locomotives was not substantially higher than steam, whereas diesel locomotives were much higher. It would be interesting to know more about this?

 

 

Seems logical

In essence a Diesel (Electric) locomotive is no more than an Electric Locomotive but carrying around it's own Power Station.

I assume in the days of 650v there wasn't a huge amount of equipment required in the bodyshell, unless you were adding a Booster set.

AC electrics need a Transformer & Rectifier as well

 

I was shown inside a EM2 at Reddish (along with a load more of my fellow schoolkids) when I was 14 or 15 but can't remember much about it.

[Compound2632]

23 minutes ago, melmerby said:

Seems logical

In essence a Diesel (Electric) locomotive is no more than an Electric Locomotive but carrying around it's own Power Station.

I assume in the days of 650v there wasn't a huge amount of equipment required in the bodyshell, unless you were adding a Booster set.

AC electrics need a Transformer & Rectifier as well

 

I was shown inside a EM2 at Reddish (along with a load more of my fellow schoolkids) when I was 14 or 15 but can't remember much about it.

 

Well indeed, electric traction has the enormous advantage of not having to carry its power generation unit around with it - something that was appreciated from the very earliest days, even though technically electrical engineering was not even in its infancy but still in Michael Faraday's metaphorical womb. Brunel (and others) tried to build a mechanical analogue but the closest approach was the cable-worked incline.

[rockershovel]

33 minutes ago, melmerby said:

Seems logical

In essence a Diesel (Electric) locomotive is no more than an Electric Locomotive but carrying around it's own Power Station.

I assume in the days of 650v there wasn't a huge amount of equipment required in the bodyshell, unless you were adding a Booster set.

AC electrics need a Transformer & Rectifier as well

 

I was shown inside a EM2 at Reddish (along with a load more of my fellow schoolkids) when I was 14 or 15 but can't remember much about it.

 

Quite so... but the whole point of the diesel electric locomotive is that it requires only fuel and lubricants, and it will go anywhere the track will bear its weight. A steam engine, likewise, requires only coal and water. An electric locomotive requires the whole infrastructure, or it is a dead hulk. 

 

I could easily believe that the loco, per se, would be a cheap build. It’s clear, from pre-war development in a number of countries, that electrification was commercially and technically attractive, and even in Germany - world leaders in Diesel engines, at the time - the diesel wasn’t a front runner over European distances (by which I include the U.K., in the sense that major conurbations are often less than 50 miles apart, and distances rarely exceed 300 miles)

 

there is also the question of why diesel electric traction is so superior to diesel hydraulic - it has clearly won that contest? 

 

 

Edited January 3, 2021 by rockershovel

[PhilJ W]

Diesel-electric has the advantage that as the full power generated is only used fully when starting from a halt a lot of that extra power can be utilised for other things such as carriage heating and nowadays air conditioning. I am aware that many of the earlier British diesel-electrics carried a boiler for carriage heating but that was because much of the stock they hauled was equipped for steam heating. They are also easier to maintain than diesel hydraulics.

[The Johnster]

10 hours ago, rockershovel said:

...the previous group of posts all seem to tend in the same direction... that the BR Standards were, for all practical purposes, robust and effective solutions to a category of locomotives which were well known to be approaching their end of service, were unlikely to undergo further radical transformation, would not be replaced or further developed and would not repay further development. 

 

The one about the boiler from 6202 seems to be a case of this, combined with "making best use of salvageable components" 

 

what is interesting, is the quote about Bulleid's Presidential Address to the Locomotive Engineers, which appears to state that the cost of electric locomotives was not substantially higher than steam, whereas diesel locomotives were much higher. It would be interesting to know more about this?

 

 

An electric locomotive drives through electric traction motors, so if you compare it to a diesel electric, you can dispense with the prime mover, fuel system, and generator and simply rectify and otherwise convert the current you draw from 3rd rail or OHLE to be suitable to feed to the same traction motors as you use on the diesel electric; a bit of switchgear and control equipment and Robert is your dads' brother.  So Bullied was quite right when he said that an electric locomotive, and presumably a multiple unit as well, is cheaper than an equivalent diesel loco, hydraulic or electric driven.  It is not the whole story though; when you factor in the cost of providing and maintaining the 3rd rail or OHLE, and the substations and kit needed to take power from the National Grid (which of course you have to pay for) to provide the specified current to the said 3rd rail or OHLE, and divide it by the number of locomotives and multiple units, then diesel powered traction becomes less expensive in comparison.

 

Bullied's take on this would no doubt have been that his railway already had a significant mileage electrified and he was talking in terms of electric locomotives for freight and hauled passenger train work, the Raworth Co-Cos.  These, taken as a standalone project, might well have compared fairly well with steam in terms of buld cost, and all 3 were probably cheaper than the Leader project.  It would, I submit, to be fair to compare steam locos doing similar work, which were basically the Woolwich Moguls, and factor in the cost of building a brand new N in the early 50s; perhaps the nearest thing to look at for costing purposes were the BR standard 4MT moguls.

 

If a Raworth Co-Co cost the same ball park to build as a BR standard 4MT, then it was a bargain in terms of availability and maintenance costs, but only where there was juice for it.  The Southern Region's solution to this was the E60xx electro diesels, a very significant success story that has stood the test of time very well indeed!

 

I remember being told by a railway manager neighbour in the early 60s that a diesel loco cost at least twice as much as a steam loco of comparable capacity to build, but that as it's increased availability meant that it could do the work of, and thus replace, 3 steam locos, it was a bargain.  In the event, loco shortages caused by a combination of reliability issues with the diesels and an overenthusiastic program of steam withdrawals saw the near collapse of the WR's timetable in 1962 whilst failed Warships blocked Swindon bays preventing new locos being built or steam overhauled suggests that this may have proved a tad optimistic; a diesel did twice the work of a comparable steam loco and cost twice as much, so you came out even but had the advantages of easier preparation/disposal and cleaner working conditions.  Truth is the diesels were underpowered and thrashed, which led to failures.

Edited January 4, 2021 by The Johnster

[The Johnster]

On 02/01/2021 at 17:01, melmerby said:

Based on a Brittania chassis, with a boiler derived from a Duchess, seems to fit in well with the "standardisation" ethos.

A Duchess boiler on a Britannia chassis would have overhung the ends somewhat!

[Flying Pig]

4 hours ago, PhilJ W said:

Diesel-electric has the advantage that as the full power generated is only used fully when starting from a halt a lot of that extra power can be utilised for other things such as carriage heating and nowadays air conditioning. I am aware that many of the earlier British diesel-electrics carried a boiler for carriage heating but that was because much of the stock they hauled was equipped for steam heating. They are also easier to maintain than diesel hydraulics.

 

More RMweb physics, I'm afraid.  Tractive effort is high on starting but power is not, because of the relation:

 

Power = Tractive effort x speed

 

As speed rises, so does the rolling resistance of a train and the loco needs to produce enough TE to balance this at the designed operating speed.  This almost always requires a diesel engine powerful enough to produce a TE at low road speed that would cause the loco to slip as well as overloading the traction motors*, so the engine is opened up progressively as the train starts away - this is clearly audible, particularly in earlier designs.

 

*TE produced by the motors is a function of the current flowing through them.  A phenomenon known as Back EMF opposes the traction voltage and works to reduce the current flowing through the motors.  It increases in proportion to motor speed and is negligible on starting when the motors are vulnerable to excessive current.

 

 

[rockershovel]

2 hours ago, The Johnster said:

An electric locomotive drives through electric traction motors, so if you compare it to a diesel electric, you can dispense with the prime mover, fuel system, and generator and simply rectify and otherwise convert the current you draw from 3rd rail or OHLE to be suitable to feed to the same traction motors as you use on the diesel electric; a bit of switchgear and control equipment and Robert is your dads' brother.  So Bullied was quite right when he said that an electric locomotive, and presumably a multiple unit as well, is cheaper than an equivalent diesel loco, hydraulic or electric driven.  It is not the whole story though; when you factor in the cost of providing and maintaining the 3rd rail or OHLE, and the substations and kit needed to take power from the National Grid (which of course you have to pay for) to provide the specified current to the said 3rd rail or OHLE, and divide it by the number of locomotives and multiple units, then diesel powered traction becomes less expensive in comparison.

 

Bullied's take on this would no doubt have been that his railway already had a significant mileage electrified and he was talking in terms of electric locomotives for freight and hauled passenger train work, the Raworth Co-Cos.  These, taken as a standalone project, might well have compared fairly well with steam in terms of buld cost, and all 3 were probably cheaper than the Leader project.  It would, I submit, to be fair to compare steam locos doing similar work, which were basically the Woolwich Moguls, and factor in the cost of building a brand new N in the early 50s; perhaps the nearest thing to look at for costing purposes were the BR standard 4MT moguls.

 

If a Raworth Co-Co cost the same ball park to build as a BR standard 4MT, then it was a bargain in terms of availability and maintenance costs, but only where there was juice for it.  The Southern Region's solution to this was the E60xx electro diesels, a very significant success story that has stood the test of time very well indeed!

 

I remember being told by a railway manager neighbour in the early 60s that a diesel loco cost at least twice as much as a steam loco of comparable capacity to build, but that as it's increased availability meant that it could do the work of, and thus replace, 3 steam locos, it was a bargain.  In the event, loco shortages caused by a combination of reliability issues with the diesels and an overenthusiastic program of steam withdrawals saw the near collapse of the WR's timetable in 1962 whilst failed Warships blocked Swindon bays preventing new locos being built or steam overhauled suggests that this may have proved a tad optimistic; a diesel did twice the work of a comparable steam loco and cost twice as much, so you came out even but had the advantages of easier preparation/disposal and cleaner working conditions.  Truth is the diesels were underpowered and thrashed, which led to failures.

 

Interesting reading. 

 

I studied miscellaneous, ie non-coal, mining engineering in the 1970s (the distinction being a purely British one, resulting from the separation of coal mining from other disciplines under the NCB). It was unusual in British terms, being a course which prepared its students to work overseas, and the “business and economics” section made no bones at all about the consequences of allowing development policy to be driven by political, rather than technical considerations. 

Edited January 4, 2021 by rockershovel

[Rockalaucher101]

19 hours ago, Gibbo675 said:

My view is that the Bullied pacifics should have been rebuilt with Caprotti gear instead of what was done to them., they would have been phenomenal locomotives.

No there's something I wouldn't mind cobbling together

[melmerby]

On 02/01/2021 at 17:01, melmerby said:

Based on a Britannia chassis, with a boiler derived from a Duchess, seems to fit in well with the "standardisation" ethos.

 

10 hours ago, The Johnster said:

A Duchess boiler on a Britannia chassis would have overhung the ends somewhat!

Not actually Duchess boiler as I clearly stated, derived from.

Edited January 4, 2021 by melmerby

[Flying Pig]

22 minutes ago, melmerby said:

 

Not actually Duchess boiler as I clearly stated, derived from.

 

Or you could do somewhat the opposite, as has cropped up on these pages before, and use a Britannia boiler to rebuild a Jubilee as a 7MT Pacific.  Discussed here and a photo of an N gauge model a long-lost member was working on, much earlier in this very thread:

 

 

[Gibbo675]

Hi Chaps,

 

The Britannia/Clan and DoG's framesets were derived form Mr Bullieds pacific classes of locomotive except that they were made heavier by riveting the horn guides instead of welding them into place, as were the proportions of the boilers except that they didn't retain the good bits that made them steam quite as well.

 

Technically, BR standards are no better than what the GWR were building in 1905 except for improved super heat that had more to do with available cylinder lubricants than metallurgy and some had roller bearings. Cabs that kept the rain off tender first and high running plates are mostly cosmetic.

 

Most of the BR Standards were unnecessary with the exception of the Britannias and the unbuilt 2-8-2. The class 4 tank engine was nothing more than yet another LMS class 4 tank, the class 5 was a black five with slightly larger cylinders and wheels, the class 2's and class 4 2-6-0  were a continuation of those LMS types, the class 4 4-6-0 was unnecessary as were both of the class 3 types. The clans were nothing more than under boilered Britannias that must have cost almost as much to build, as they were worked over the main lines the axle weight was of no consequence.

 

On the whole a job creation exercise for keeping the drawing office from doodling, the tool and makers busy and giving stores yet more stuff to deal with.

 

Gibbo.

[Rockalaucher101]

I'm actually looking into the idea of creating a caprotti bulleid now.  So much for my new years resolution.

 

What are we thinking though? What springs to mind?

Air smoothed or rebuilt, west country or merchant navy...

 

Decisions decisions.

[PhilJ W]

A rebuilt but based on one that was not rebuilt. If the rebuild program had continued to include all of the Bullied pacifics a Caprotti one would have almost certainly have been tried. It might be worth looking in the records to see if one was planned.

[Rockalaucher101]

31 minutes ago, PhilJ W said:

A rebuilt but based on one that was not rebuilt. If the rebuild program had continued to include all of the Bullied pacifics a Caprotti one would have almost certainly have been tried. It might be worth looking in the records to see if one was planned.

So one of the light pacifics then.

Don't suppose you know where I could check if they ever thought of using caprotti?

[Gibbo675]

42 minutes ago, Rockalaucher101 said:

I'm actually looking into the idea of creating a caprotti bulleid now.  So much for my new years resolution.

 

What are we thinking though? What springs to mind?

Air smoothed or rebuilt, west country or merchant navy...

 

Decisions decisions.

Hi There,

 

Austerity Q1 style would be my answer, one set of gear between the frames driving three cylinders just like this one.

 

 

Gibbo.

[Rockalaucher101]

1 minute ago, Gibbo675 said:

Hi There,

 

Austerity Q1 style would be my answer, one set of gear between the frames driving three cylinders just like this one.

 

 

Gibbo.

Now isn't that something. Not sure I could pull it off but I'll add it my list of things to try out. Right after I finish my overhead electric A4