The V4s

[Pyewipe Junction]

From time to time I note an approving comment about the V4s - usually that they would have been built in quantity had Gresley not suddenly died. I find these engines intriguing and mysterious. They were both withdrawn before I started trainspotting (? boiler replacements not justified) and anyway, they were always based in Scotland.

I note that they were intended as a general-purpose mixed-traffic design with a high RA, but another thing I find interesting is that they had 5' 8" driving wheels (the same diameter as the K2s and K3s). The only other mixed-traffic locos I can think of with wheels of this diameter are the GWR Granges and Manors, both of which were designed for a specific purpose. The Halls and Stanier 5s had 6' 0" wheels and of course the B1s and BR 5s had 6' 2" wheels.

I can imagine the V4s doing good work on the M&GN and GE lines but I can't visualise them hauling expresses (for example, Cleethorpes - London, Norwich - London and on the the GCML) like the B1s did. So I guess what I am really saying is that my feeling is that the V4s may ultimately have been limited in the duties they could perform.

Can anyone shed any light on what the operating intentions were for this class and how many were to be built?

[2512silverfox]

I have never seen anything much about the design philosophy for the V4 but I do know that Bantam Cock was trialled in East Anglia before being sent to Scotland. One must assume that it was not a success there, and did not fill any particuoar gap in the motive power scene. On the other hand so much may have happened had HNG lived longer and WW2 not intvened!

[dlester]

I can imagine the V4s doing good work on the M&GN and GE lines but I can't visualise them hauling expresses (for example, Cleethorpes - London, Norwich - London and on the the GCML) like the B1s did. So I guess what I am really saying is that my feeling is that the V4s may ultimately have been limited in the duties they could perform.

If a V2 (6'2" Kylchap) can do 101mph down Stoke Bank, and an A4 (6'8" Kylchap) can do 126mph in the same location, how fast could a 5'8" locomotive go, with a well-designed front end?

Can anyone shed any light on what the operating intentions were for this class and how many were to be built?

Extremely doubtful that there's much unpublished data available now. For what it's worth the locomotives were trialled over much of the LNER system, and I seem to recall that they were something that interested the shed masters and enginemen involved (source probably RTCS).

I figure they'd have been used much like the postwar Peppercorn K1 and Thompson B1: as fast secondary passenger and fast goods locos, replacing ageing Atlantics and 4-4-0s amongst others.

Dave

[Atlantic 3279]

Did not the older generation mixed traffic locos such as the B7, B16, and (if you count them) the J1/J2 not also have 5' 8" coupled wheels? Is this really an unusually / unsuitably small size for mixed traffic work? Could the 6' 0" and 6' 2" size of the B1s, halls and black fives have been partly brought about by the derivation of these designs in part from passenger 4-6-0s whose designs were already proven or at least tried, making it desireable to stick existing suitable parts and ideas where possible, without having to totally re-draft the chassis layout to suit much smaller wheels? By the 1940s, would it be true to say that improved valve events, steam passage layouts, greater fluidity of highly superheated steam at high pressure, better bearings and better lubrication were all starting to make driving wheel size less of a restrictive consideration in a design anyway? In the same way that it is being suggested above that 5' 8" was bit on the small side for a loco to be truly "neutrally" balanced between pasenger and goods work, leaning a little too much towards slower running, could it also be that 6' 2" leans a little the other way? As the LNER had no standard coupled wheel pattern of a diameter between 5' 8" and 6' 2" then short of creating a new wheel pattern Gresley and Thompson both had to choose, and came to different conclusions, but did it matter that much? Perhaps Gresley considered that the 6' 2 coupled wheel of the V2 was a bit of a "special" anyway, created just to suit a loco that was mainly meant in the first place for hauling the Scotch Goods or deputising for a failed pacific, i.e definitely leaning towards the fast side of mixed traffic, so he went for the next available existing smaller size for the more general-purpose V4 concept?

[Multiprinter]

What I've never understood is the use of 2-6-2 rather than 4-6-0 the latter being a bit more sure footed. It strikes me that the V4s were overdesigned when a simple 4-6-0 or even 2-6-0 was what was needed as was seen when Thompson produced the B1.

[Atlantic 3279]

With my tired mind late last night I forgot that the origin of the 6' 2" wheel size for LNER standard designs lies with the P2s before the V2s, and surely that is further evidence that this was primarily considered to be a size to suit passenger trains. However, I also overlooked another possible weakness in the suitability of 5' 8" wheels: At not quite 10% larger than the 5' 2" of the K4s, there might be a risk of similar trouble with loosening of the Gresley middle big-end if regularly used at speed, so that might not run in favour of the V4 design.

[kudu]

It strikes me there are two separate questions here:

(1) what were Gresley's aim in producing these machines, in particular, what performance did he expect?

(2) would his aims have been fulfilled?

I find it hard to imagine they could have performed duties such as the Kings Cross - Cleethorpes expresses as the B1s could, but appearances can be deceptive. (Interesting that their TE was higher than a B1 but their weight lower.)

And even if they could, would their maintenance demands have matched those of the B1?

Don't bother measuring the wheels - count the cylinders (especially the inside ones).

Kudu

[manna]

G'Day Gents

Going back a bit to size of the wheel to possible speeds--dlester a 9F was timed at 90mph down stoke bank and they only have a 5' wheel and L1's have been timed at 75mph (good luck)K3's have been time at 75mph and they were a very rough riding loco but had 5'8" wheels, I think with V4's we should be asking also how free steaming were they, if they were I would say it might have been possible to have got one into the 90's down stoke without to much drama, as I've heard they were pretty good riding engines.

manna

[harvester]

Wasn't one of the purposes of trailing wheels to enable better proportioned fireboxes? Wider grates giving better gas flow ratios?

[Pyewipe Junction]

It does rather seem that the 4-6-0 was not Gresley's wheel arrangement of choice. During his time as CME he oversaw only one 4-6-0 class, the B17s, and the design for them was palmed off onto the NBL Company. I find this interesting, because a leading bogie must must be inherently more stable at speed and on poorly maintained/ballasted track than a pony truck - cf the Sevenoaks accident and various incidents involving V2s. Having said that, Gresley took no steps to replace the the 4-6-0 designs of his predecessors and in fact actively sought ways of improving them. He even built more immediately after grouping.

I do like the symmetry of the 2-6-2 design and agree that Gresley probably preferred it because it allowed for a wider firebox.

Another interesting thing about the V4s is that they has 250psi boilers (and one of them had a thermic syphon, just to get in before Bulleid!). Gresley must have become a 'born again' convert to high pressure boilers for general purpose locos, having previously reserved higher pressure boilers for higher performance types. Obviously he became satisfied that the higher pressures did not lead to too much extra maintenance.

I have no doubt that the V4s would have been capable of 90mph down the Stoke Bank, but my initial question was whether overall they would have been as effective as the B1s for all types of duties.

[Blink Bonny]

It must be remembered here that Edward Thompson did his level best to remove HNG's influence from the LNER, presumably because he was overlooked for the top job in favour of HNG and, it has to be said, produced some fairly ordinary locomotives, B1 and K1 apart. His rebuild of the K3s was so poor that no others were contemplated and the L1s got themselves the nickname of "Cement Mixers" due, presumably, to their habit of riding poorly and knocking themselves to pieces!

Given a chance the V4s could well have been a success because the Eastfield crews who knew them well regarded them as a Rolls-Royce to do the job of a Ford. They steamed well, rode well and were capable of great things. Whether or not the three cylinder arrangement would have stood the test of post-War service is one of those things we could debate until the cows came home, I reckon.

Such is the fun of history!