Large and Small locomotive economics, ex-West Somerset Railway developments

The last went in 1949 but the two there now have an authentic IOW pedigree. They (both re-boilered) are limited to 80 tons tare largely because of their age but they have worked more in the past and are clearly capable of doing so now. I once rode in the guards van of a three Brighton bogie train hauled by W8 (there's authenticity for you) and observed her accelerating the train up 1 in 68 with the valves feathering and without any great effort. You can see why I tend to be cynical about people claiming that big locomotives are necessary on 25 m.p.h. tourist railways. A "big locomotive" on the IOWSR is a 2MT.

Paul H.

 

You were impressed by a small engine hauling a light train...

 

Impressed by a tiny locomotive hauling a train of a sensible weight with a capacity of approx. 200 passengers on a coal consumption of, so I was told, around 1 ton per day. This formula would not work everywhere but would do so far more often than the people looking for excuses to run over-elaborate equipment would acknowledge.

PH

 

Where did I say that the vacuum had to be released? Always shunt with the vac brake operational but the vac has to be destroyed (not released) before you go between. As for Buckeying with an A4, there's many a person would prefer to use the emergency screw coupling rather than the Buckeye! It can be a real pain trying to Buckeye up on the curve of Pl.3 at Grosmont. Quite often it takes several attempts before they'll take. That means dropping on to the stock, winding it into forward, doing a pull test and stopping before you hit the gates if it doesn't take then destroying the vacuum whilst the guard goes between and adjusts the heads then, when all clear,, winding it into back gear and re-creating vacuum before repeating the whole process. After three or four attempts at this you start to curse the fact that Gresley fitted corridors to some of his tenders.

 

Steve - I and PH should have read your post more carefully as it was obvious when re read you were talking about the buckeye release chain not the vac release string. I agree curves and buckeyes can be a problem.

Coupling two standard gangway coaches on your own is IMHO worse than a recalcitrant buckeye..
Shunt stock together and destroy vac -indicate going under - both vac pipes off dummy
Attach screw coupling
Come out from between climb up one side, there may not be a step, balance on buffer casings and unhook gangway from stowed position
Climb back down go under and climb up the other side - release the gangway pull together and clip.. Couple lighting jumpers
Climb back down again back under and back up on to the buffers and fit clip.
Get back down ataching lighting jumpers as you go
Back underneath to couple steam heat and vac
Come out and get brake blown up for a continuity test

Having to have a couple of goes with a buckeye is in contrast a doddle, at least for the guard.

 

It's all relative though Paul, a little engine hauling a small train is the same as a medium size engine hauling 5-6 Mark 1s on a similar gradient as you mentioned. It's not like your Terrier was hauling 7 Mark 1s that day.

 

Again the point is missed! It's nothing to do with the merits of the performance as such, simply with keeping costs in check. There are those on this thread who would have it that operating with small motive power somehow puts an undue strain on the machinery and use this argument as a justification for using the big stuff. The example cited by me was to show that by keeping a careful watch on tare weights, problems of this kind are illusory.

This thread has strayed much too far so I would comment an article in the current edition of (yes) Steam Railway which gives quite a detailed account of IOWSR matters including financial issues.

PH

 

Do you think a Terrier could haul 7 Mark 1s up a 1-68 gradient? Is this the point I've missed? I'm not sure what you're aiming at.

 

"Blood and Sand" is the only reasonably polite reaction I can have to your posting! Of course it could not and doesn't need to for train weights are kept low. Similarly the South Devon Railway's ex Weymouth harbour tramway pannier tank does a perfectly decent and economic job in the Dart Valley. The point is, keep tare weights down and you don't need over-sized motive power to haul services at 25mph on a tourist railway. Money thus saved can put towards other things, for example the re-boilerings which most standard gauge lines have conspicuously failed to achieve.

Go and read the article I referred to in my previous posting.

PH

 

But people have already pointed out that there is a need for 7 coach trains on some lines where they need decent sized engines to pull the trains. You have this 'one size fits all' theory that doesn't actually apply to many places. What other lines are hauling around 7-8 coaches that don't need to? It seems to me that you have this view and everything has to fit into it regardless of the evidence that suggests otherwise.

 

Well, the GCR could probably get away with a Terrier/P on their 7-8 coach trains. 300 T (say) on 1 in 176 is 3820 lbf plus 300 T @ 4lbf/T rolling resistance adds another 1200 lbf. Next to no curve resistance so you're only looking at around 5-6,000 lbf T.E. Fairly level grades out of Loughboro' & Leicester would help with getting the train on the move and those coach bearings well lubricated..
Be interesting to try!

 

It is their opinion; I have mine, gained very largely from what I have seen. Many places don't have platforms big enough for long trains but plenty of these use motive power that incurs un-necessary cost just to move its own weight around. Of those that do have platforms for long trains, one that comes to mind is the Paignton and Dartmouth. Here the largest boiler is on the 2-8-0T which has, I understand, a Swindon No.4. There is a prolonged substantial climb out of Dartmouth but (repeating myself) 25m.p.h. is the limit. There is much about the P&D which is not particularly to my taste but there is no doubt it is businesslike. It should be possible to be both fairly businesslike and reasonably authentic. A few lines are. All need to be.

PH

 

I am struggling with the logic of this. The present day passenger usage of many heritage stations was never foreseen when built nor in their previous life,hence the short platforms.Every line is different,some do use smaller engines on short trains, others have had to meet demand by extending platform lengths ,provide longer trains with bigger engines . Are you advocating the major crowd pullers revert to the authentic passenger figures, train lengths etc prior to their closure?

 

Or perhaps Tiffer PH is advocating platform lengths as a yardstick for train length, remind me again how many fit in the main at Minehead is it loco and 14. So perhaps he is suggesting we halve the number of trains but double the train length so we only give our 2-8-0s half the time in service, the mind boggles. faol

 

I agree that in some cases, train lengths could be more authentic. It would be much better if the GWSR's trains were 12 coaches long hauled by a castle...

 

I am struggling as well but to understand why people find this so difficult to grasp! Could be summed up as "Don't use a King when all you need is a Manor" and don't kid yourself you need that King by adding more carriages than the trade offering really justifies.

PH

 

I have visions of a Castle between two auto-trailers...................
(for the off-peak services, you understand).

 

Not about WSR, but responding to the alternative 'thread within a thread'.

It is, in my experience, a fact (gained from practical management) that in the environment of a busy heritage railway there is a false economy in using locomotives that are too close to the margin in terms of power. In terms of coal consumption on the average loads concerned there was little difference between using class 2/4 power or class 6 power. Coal consumption was reduced with the use of even smaller engines - but not to the joy of the fitting staff (and overtime payments) to keep the service running. This was in a situation where there were no wooden bodied coaches to use - so the reality of having light but high capacity trains was just not there. The reality was that for much of the time the railway ran/runs at capacity - with little difference in coal between class 2 and 6 locos on the same load and little choice of alternative stock to carry the loadings required.

My summary - not much difference in coal, but running too close to the margin in terms of power leads to a potentially exponential increase in running maintenance costs (let alone wear and tear revealed at a full overhaul).

As alluded to by someone else above, the biggest variable in coal was not the loco - but the crew!

 

Only when it's back to double track.......

 

If we did see 12 coach trains at GWSR surely to be authentic they would not stop at Cheltenham Racecourse, Winchcombe Toddington or Broadway. Stratford fast to Cheltenham would be more likely