Austerity 2-8-0 query

I'm a bit late to this discussion but I can understand why the Austerity 2-8-0's were referred to as being based on the 8F yet had little in common with them. In a nutshell, Riddles wanted a loco that would do what an 8F would do but had to have the minimum of non-ferrous materials (essentially confined to pipework, steam fitings and bearings), a minimum of castings, be cheap and easy to build, be able to operate in th UK and Europe (air and vacuum brake) , be easy to maintain in the field (e.g hydrostatic and syphon lubrication and steel plate wherever possible) and last long enough to see the war out (cheap and cheerful). That's never going to be anything like an 8F but is based on what that locomotive could do (loads hauled) and go ( route availability.)

 

It would be very interesting if numbers can be put on reasons for scrapping.
Up til mid 40 WD had a lot of 8fs built and after jan 43 only Austerities were built.
What was scrapping rate history and why?

 

I don’t know myself. I have models of both and examining them together I can see the 8F origins as a basis. It’s very obviously not an identical class, it is massively simplified, and it has design changes that allowed for cheaper manufacturing and maintenance, but it has a lot of the Stanier look to it.

 

Thanks

Looking at the comments so far........

The WD cost about £500 or 5% less than the 8F

Its a good measure, BUT.......

Presumably casting is cheaper than fabricating - at least to my non technical mind BUT if you are limited in the number of castings you can make but you have a lot of semi skilled workers who can turn out fabrications even if they are not necessarily cheaper then thats the way to go in WW2

 

The WD 2-8-0 was actually tested along with a WD 2-10-0 in an official BR Report (Bulletin No 7 in 1953). Like a number of locos tested, the steaming was poor. The blastpipe was reduced in diameter to achieve 19500lbs/hr of steam. It could not be tested above 40mph as the riding was too rough, could not be worked at cut-offs longer than 50% due to slipping, and it was incapable of doing much with lower grade Blackwell coal. The valve events were actually not bad notwithstanding the change in radius rod suspension. Apart from the boiler and extra axle, the 2-10-0 (which also had the blastpipe diameter reduced) was basically identical, same cylinders etc and was superior to the 2-8-0 as to riding, boiler efficiency and being able to burn the lower grade coal. Presumably the BR depots just had to put up with the 2-8-0s until I suspect in a lot of cases the traffic disappeared. On the other hand, they did have an impressive number of lamp irons on the rear of the tender.

 

If you go into BRDatabase - the Complete British Railways Locomotive Database 1948-1997, and in the second box on the left click "Classes" then "Steam" then "LMS "or "ex-WD" you can pull up full class lists of both types and that should give you enough data to play with.

 

Any ideas as to the speed of construction of each type? If it were possible to build x+y WDs in the time it took to build x 8Fs that could account for the switch.
No evidence to back that up, just wondering.

 

Thank You .
Have not seen it before.

 

You're overlooking the minor matter of the complete replacement of all steam in those 20 years. No correlation between scrapping rate and usefulness should be assumed given the mass extinction nature of what happened.

 

I've also heard that when WDs were given heavy general overhauls post war they were reassembled with considerably more care and precision than they were put together with in the first place. Which would be both sensible and unsurprising.
There's quite a difference in weights between the diagram huochemi posted from the 1948 report, and the 1947 one I posted from the Swindon DO diagrams book. I wonder if that's significant. The Swindon drawing appears to show them reclassed from Red RA to blue. The static weights put them well within Blue restriction, so classifying them as red suggests a dynamic consideration .

 

Those Swindon weights look very even (no variation in weigh on each set of drivers; and no variation on each set of tender wheels).

You would expect some small variations in weight if different drawing offices had different conditions for assessing weight. The precise weight of a locomotive will vary depending on whether it is measured in steam or cold; how high the water in the glass is and how much coal is on the grate - the LBSCR I know had standards for weighing, and I assume every other company did as well, but those standards could have varied between companies.

Tom

 

A problem with WDs as far as crews were concerned was the fore and aft surging as speed rose, increasing from 25 m.p.h. on to the point where anything above 40 m.p.h. was bordering on dangerous. The reason was the lack of reciprocating balance. This reduces the fore and aft forces but the downside, as it were, is to rotate them through ninety degrees into vertical forces more commonly referred to as hammerblow. The nil reciprocating balance means that these engines should not have imposed hammerblow so their RA would be determined by their static weights, no 'dynamic augment' included.

 

I’m not sure about the loco but the tenders certainly had compensated springing, as can be seen on any photo showing the tender. This would equalise the weight distribution over the axles.

 

Yes.
But it's in the book I cited yesterday, which today I'm not near.
The replacement of castings had a lot to do with that, ie if you did a Stratford-style record-breaking fastest build from a pile of pre-assembled parts, it may have been no faster to build than an 8F but the availability of casting resource/non-ferrous materials etc was the determining factor.

 

It's a fair point, if Austerities were built later than 8Fs, why were they scrapped first? IIRC, the last engines in BR service were 8Fs and black 5s, (excluding the last Brit kept for last day special), ie 9Fs and other BR standards went first.

 

Nothing to do with locomotive classes. The north west happened to be the last area with steam locos. You only have to look at the north east area which finished a year earlier with their J27s, Q6s and WDs.

 

I'd understood that the fleet in the north west was simply what remained as the area in which steam worked shrank, rather than that the Stanier types were specifically retained rather than the Austerities.

 

So much for that theory then!
I've attached the complete page. I was given it by a former Swindon Draughtsman, so it is authentically ex Swindon DO. Its drawn in the Swindon DO style.FWIW I've gained the impression that tender weights in Swindon diagrams could be quite nominal, because I've seen tenders that one would assume to be significantly different given the same weights. OTOH Swindon would issue new diagrams for changes in locomotive weight.
The initials FCM on the stamp would presumably be Frank Mattingley, appointed Chief Draughtsman in 1945.

Possibly as simple as what was in use at the last sheds. It wouldn't be sensible to go swapping a new type into a shed for the last year or two. To my mind its pretty futile to try and draw many conclusions from the last few years, when management had enough on their plates trying to make dieselisation work without worrying too mch about getting the last bit of efficiency out of the dying steam fleet.

 

Don't put too much credence on the axle weights shown in the weight diagrams, and certainly not LMS ones. For the 8Fs they were always given as 8T 10cwt, 15T, 15T, 16T, 16T, not only remarkably similar but also spot on at whole tons. The Lizzies' engine weights were always given as 104T 10cwt; as built 6200 came out at 111T 18cwt, and while some weight reduction was effected it would have been hard to lose almost 7 1/2 tons. The important point wasn't so much what the engine weighed but that the Chief Civil Engineer never learned the truth!