'Good Engine's'

[manna]

G'day Gents

Thinking the other day (hard I know) why there were 'good' engines and 'bad' engines 60001 Sir Ronald Matthews, was I believe was a 'bad engine (poor steamer !) yet 60033 was always called a 'good' engine, what made the difference between a good 'un and a bad 'un, when there suppose to be the same class, same engine almost......

manna

[Hatfield Shed]

They were all hand machined and assembled - this applies to all UK steam locos - and small dimensional variations are inevitable. When these affect draughting and valve events in particular, the effects can be very marked. A major clue in the Gresley pacifics is that with the Kylchap ejector fitted, they became much more uniform in performance, the poorer steamers pulled up to the level of the known better performers.

[manna]

G'day Gents

Thank's Hatfield Shed, so it all comes down to the odd 1/64th of an inch here and there, amazing

manna

[wlkr]

Considering that a steam locomotive consisted of two distinct parts, the boiler and the "engine", which one of these components can the finger be pointed at when you find you have a "bad" locomotive? Take for example B1 61379 "Mayflower", a long time Immingham engine. Well known as a "bad" engine it carried six boilers in it's working life so was it the "engine" that was at fault? I'm afraid I don't have a clue but I was at school with a few lads whose fathers were drivers at Immingham and we asked them to ask their fathers what was wrong with it. The answer was invariably it wasn't up to much but one lad came back and said, as far as his dad was concerned "if you see a clean Immingham engine it's a bad un 'cause they haven't got the time to clean the good 'uns!" That explains why 61248 "Geoffrey Gibbs" and others we saw more often were in an appalling external condition!

[Hatfield Shed]

It could be quite a lot more than that! Among those that left descriptions of working on 'The Plant' I find Bill Harvey particularly clear about the limitations in Doncaster's manufacturing equipment and consequent technique, and the management system. With locos typically built in small batches, often with two or more erecting teams working in parallel and operating under a form of piecework; the components available to the erecting teams would be very carefully inspected, and those that required the least fitting work seized upon first. The end effect of this is that the final locos of the batch would major on the components which required the most fitting attention: that's a recipe for non-uniformity from my own experience in manufacturing engineering.

Add to this that the lead erector was responsible for valve setting, and differences in end result in engine performance are going to creep in. One of the 'bones of contention' in valve setting was allowance for thermal expansion, because of course it had to be done completely 'cold'. Custom and practise came into play here: how you did it depended who you had trained under, and there were significant differences in opinion between the major workshops of the company which 'travelled around' the LNER as engineers moved within the company, and were never eliminated, as they were still in evidence in the BR period based on what Peter Townend and others observed.

Fortunately the steam locomotive is a tolerant device and will work even if less than optimally set up, especially when carefully handled by an experienced crew. But there's the difference between an optimum build of a given design, free-steaming and easy to manage whatever the power demand; and one that is 'crabbit' in some way and had to be nursed along to give of its best, especially when maximum outputs were required.

[wlkr]

A belated thankyou for the reply "Hatfield Shed" on '1379's malaise. Appreciated.

[Hatfield Shed]

Likewise appreciated, but we still don't know exactly what was wrong with 1379! I do find it a little puzzling that this sort of thing was tolerated, as there were good engineers who could probably have fixed most of this, if tasked to 'get out there and sort it'.

A good example is found in one of Dick Hardy's books, where he was on the footplate of Norwich shed's then notoriously shy steamer among its B1s. He describes trying every trick he knew and getting nowhere until he pushed most of the fire well forward, leaving the thinnest covering on the rest of the grate; with which the machine 'came alive' and steamed freely giving them a good trip. Now I can analyse that readily: clear evidence of very uneven draughting across the grate; plenty of air forward to sustain good combustion there and maintain a large depth of fire, insufficient air at the top of the grate. (With a more even depth of firebed over the whole grate you would have burn through at the front, and excess air admitted; with insufficient air near the firehole to readily start and maintain combustion of fresh coal: consequently much reduced heat supply and the boiler is a shy steamer.

This plagued the steam railway to the end: famously DoG had a poor rep, but - again Dick Hardy - when handled by a crew well experienced with the single chimney Gresley pacifics; thin firebed with little and often firing, full regulator and small cut offs adjusted as the load required, it performed very well indeed.

[2392]

This is an area I've always found somewhat curious. Granted there would be minor differances between a pair of the same type of loco, due to different working methods of the workshop staff or even workshops. Being a poor steamer can dog an engine throughout it's service career, despite having their boilers changed on a regular bases when being "shopped". Dominion Of Canada being a case in point, OK she hasn't steamed in 50 odd years since withdrawn and presevred. This in turn begs the question why is the boiler a "bad'un" on this loco , where it won't steam even with the best coal and brightest fire, yet when removed, overhauled and fitted on the that loco of the same type it'll steam like there's no tomorrow on a picture of a lit candle [Ok a little OTT, but you know where I'm coming from i.e. really rubbish low quality coal].

[manna]

G'day Gents

Some wonderful information coming out, I like the bit about 'Mayflower', six boilers and still a bad one.

manna

[StevieG]

As an almost ignoramus as to what firing and driving steam could/can involve, I am amazed as to what skill was/is required in effective firing alone.
Many thanks for such enlightening information !

[Hatfield Shed]

The difficulty the steam locomotive engineer is presented with is that it is really only the complete locomotive that can be tested. (Unlike with an i/c engine, generator, traction motor, gas turbine, on all of which the performance can be be fully assessed 'on the bench'.) That's why Gresley pushed so hard for a static test plant in the UK such as the French had at Vitry, and which he shipped out the P2 for trials on after it was run in.

There's six major subsystems which make up the steam loco and determine its performance:
Frames and wheels: the rolling vehicle.
Grate and ashpan.
Boiler.
Superheater.
Engines.
Smokebox and blast arrangements.

All of them have to work properly, but can only be tested when assembled into a complete loco, none of them can be fully assessed independently. (I owe this to the late James Little, a man who trained under Bulleid at Inchicore. What had previously seemed complicated was made very simple when explained in this way.)

This is an area I've always found somewhat curious. Granted there would be minor differences between a pair of the same type of loco, due to different working methods of the workshop staff or even workshops. Being a poor steamer can dog an engine throughout it's service career, despite having their boilers changed on a regular bases when being "shopped". Dominion Of Canada being a case in point, OK she hasn't steamed in 50 odd years since withdrawn and presevred. This in turn begs the question why is the boiler a "bad'un" on this loco , where it won't steam even with the best coal and brightest fire, yet when removed, overhauled and fitted on the that loco of the same type it'll steam like there's no tomorrow on a picture of a lit candle...

That immediately tells you 'not the boiler'. Now, Peter Townend who was the final KX shedmaster, had DoC at the end of its career, and having finally persuaded BR's management to retrofit the Kylchap exhaust found that the 'lame ducks' were made into good performers on which any crew could obtain results. So draughting just not quite right in some way on DoC in single chimney form. Didn't take a lot in what was a marginal* smokebox and blast arrangement on the pacifics to seriously impede performance. (It was his opinion that the only reason the A4s were not all Kylchap fitted by the LNER was that the patent rights to the Kylchap ejector expired in 1941, and the loco committee were waiting for that, as there was no doubt of the success of this fitting on both the one A3 and four A4s that had it. But the war intervened, SNG died and all was forgot.)

* What is perhaps not often realised is that within the UK loading gauge, for locos with the 2,500+ boiler horsepower potential of a pacific, the simple blast pipe, petticoat and chimney system is fast 'running out of road' in terms of vertical space to produce an arrangement which efficiently entrains the flue gases in the exhaust, and thus produce a reliable draught for the fire proportional to the power output required. (The Goss formula devised by the professor at Purdue whose name it bears made this clear in 1905.) The same limitation was run into in Europe earlier than the UK, and the various 'entrainment enhancement' systems such as the Kylchap, Le Maitre, Giesl, are responses. Notice that in the USA with much greater vertical height available, simple blast arrangements were effective to the end with machines in the 8,000+ boiler horsepower class, far larger than any European locomotive.

[wlkr]

Another little gem popped up last Sunday evening whilst enjoying a few pints in my local and discussing the Immingham B1's with a couple of retired footplate men. One of these regulars is a former BR fireman who was based at Hornsey and 40B during steam days. He remembers an occasion at Hornsey when a loco himself and his mate were rostered on was changed at the last minute by the chargehand, foreman or whoever because, as the man said, refering to the booked engine, "that things no good, it's so far out of line you'll be lucky to get it to Finsbury Park"! Or words to that effect but with plenty of colour!

[Nova]

for someone that hardly remembers BR full stop (born the year of privatisation) let alone steam in regular use all of this makes for a fascinating read

[manna]

G'day Gents.

Rereading this thread a sentence popped out and caught my eye, about the patent rights for the Kylchap chimney/ejector, if it was so good for the loco, and produced a saving in coal and a big increase in power, wouldn't the payment for the right to use the Kylchap system, have paid for itself quite quickly, and been a win/win for the LNER.

manna

[Hatfield Shed]

Here's one of the opinions on that front, in the post war period when trialling whether general fitting of the double Kylchap arrangement could be justified on coal savings, for the A4s built as single chimney machines with a conventional blastpipe.

"Initially the results were inconclusive as the double blastpipe loco romped away, easily arriving before time, and recovering any time lost from other causes..."

It needed a repeat trial with an inspector instructed to 'curb the drivers enthusiasm' and to generally drive for economy rather than performance, to demonstrate that a real coal saving was achieveable on the Kylchap equipped locos.

Top Shed pp153 - 160; Peter Townend (whom happily I observe is still very much in life at an advanced age).

There were other significant advantages to the locomotive's maintenance state too; and as any manager will know improving the equipment in the hands of a workforce typically 'goes over' very well indeed. My guess from the above is that in ordinary service, it wasn't saving coal; but there were other worthwhile benefits to the operational performance.