Possible Gresley 4-6-0

[Pyewipe Junction]

On page 21 of Gresley Locomotives by Brian Haresnape there is a diagram of a three-cylinder 4-6-0 that is described by Haresnape as 'an improvement upon both the K3 2-6-0 and B17 4-6-0 types'.

This engine would have had 6' 8" driving wheels, a 220lb psi boiler and a tractive effort of just over 31,000lbs. In other words, around the BR class 6 power classification. The date of the diagram isn't stated, but from its place in the text I would assume it to be around 1935/6.

It's hard to see how it would have replaced the K3s, as its driving wheels would have been more suited to express passenger work. And with a loading of 22 tons on the driving wheels, surely it couldn't have been considered for the GE section.

Does anyone know how far this proposal got, and what work this engine was intended for?

[Danby Wiske]

I've just been reading The LNER 2-8-2 and 2-6-2 Classes by J. F. Clay and J. Cliffe, and they mention the 4-6-0 design, considered as an alternative to the V2:

Early in 1935 we heard the first hints of the coming of the V2s when the LNER announced its intention of building some engines for "heavy long-distance work of the type not yet finally decided upon".

In other words, they weren't quite sure what they were looking for!

Two designs were considered, a 4-6-0 and the 2-6-2, which was finally selected. The proposed 4-6-0 was described in some accounts as a "Super 'Sandringham' ", but actually it could better be called a shortened Pacific. There was, at one time, the possibility that both 4-6-0 and 2-6-2 would have been built as the 4-6-0 was attractive for use on lines with short turntables, bur when the 2-6-2 established itself the 4-6-0 was abandoned.

Both quotes are from page 60 if you have the book...

[Pyewipe Junction]

Thanks for that.

At least Gresley was considering a 4-6-0.

Now if he had been Churchward, he would have built one of each and compared them.

[Danby Wiske]

Now if he had been Churchward, he would have built one of each and compared them.

Churchward probably had more money to splash around than the ever-impecunious LNER!

[Hatfield Shed]

On page 21 of Gresley Locomotives ...It's hard to see how it would have replaced the K3s, as its driving wheels would have been more suited to express passenger work. And with a loading of 22 tons on the driving wheels, surely it couldn't have been considered for the GE section. Does anyone know how far this proposal got, and what work this engine was intended for?

The intent was a single design that could undertake all the work currently allocated to K3s and B17s - the latter only outside the ex-GER routes for which it would be too heavy - to meet the increasing demands for speed and loading.

The very similar tractive effort estimate to the K3, and a driving wheel diameter to match the B17 should have fulfilled both expectations.

It's an insurance policy, reflecting the deep conservatism of the mindset of the time : the V2, like the first GNR pacifics, was a venture into the unproven for the UK; best to have an outline scheme in our back pocket, for a locomotive type that there is precedent for elsewhere in the UK. There was some doubt at the time concerning the safe maximum speed with a leading pony truck on a heavy locomotive, with clear potential to achieve the 90mph line limit given experience with the pacific development.

The major design tasks for the 4-6-0 would have been the boiler and frame layout to accomodate it, as the front end is 'as a pacific'. That would be where to look for drawings to assess how much effort was put into the 4-6-0, before the trialling of the first five V2s revealed that it was the desired solution, and the class was put into production.

[Pyewipe Junction]

Now if he had been Churchward, he would have built one of each and compared them.

Churchward probably had more money to splash around than the ever-impecunious LNER!

It is a false economy to think that money would have been wasted by producing two examples for comparison.

After all there was enough money available to produce the 'Hush Hush'.

[Hatfield Shed]

Then again, by this date the LNER and LMS were communicating on design matters, and Doncaster would have had a good idea of how the three cylinder 4-6-0 developments by Stanier's team were proceeding. It was observation of the Black five that guided the mixed traffic 4-6-0 that the LNER did design, acknowledged by Thompson in correspondence to Stanier.

[Pyewipe Junction]

Then again, by this date the LNER and LMS were communicating on design matters, and Doncaster would have had a good idea of how the three cylinder 4-6-0 developments by Stanier's team were proceeding. It was observation of the Black five that guided the mixed traffic 4-6-0 that the LNER did design, acknowledged by Thompson in correspondence to Stanier.

...and we all know where the Black 5 came from, don't we?

[john coffin]

I think the Hush Hush is such a separate development that it should be ignored when trying to consider "normal engines".

Almost certainly part of the cost of Hush Hush was covered by the manufacturers of the boiler. But also I would have thought that at a time
that the LNER was promoting Streamlined locos and trains, it was a no brainer for the publicity department.

In fact at that time, most of the other railways were experimenting with "odd" new developments, so it is pretty certain that the LNER had
a special budget for such things, whereas without doubt a new 4-6-0 or the V2 design were "Standard" in that they basic premise was established.

Paul

[Pebbles]

I first came across this in F A S Brown's "Nigel Gresley Locomotive Engineer" which I purchased in around 1968. RCTS Vol 10A gives greater details, and that the proposal originated in 1936. There are to my mind a number of features that point to an old proposal being revamped in response to a demand for a more powerful engine than the B17.
As has been pointed out the line diagram shows an extended K3 firebox linked by a tapered boiler to an A3 smokebox. The diagram also points to the use of the A3 cylinder and valve gear arrangement. At this time (1936), the A4s were being produced and I cannot believe that their arrangement would not have been used - after all if you are make new parts then make the most modern. Whilst we have much of Doncaster influenced pacific in the design the cab also saws a Darlington influence. This could have been understandable as within the LNER group Darlington and Gorton would have had the 4-6-0 expertise.
I speculate that an original proposal could have resulted from the performance of the GWR Castle class. Is it not possible that the question would have arisen as to why build an engine as large as an A1 when a smaller - and therefore cheaper - engine could do the work. The performance of the Castle class was clearly a factor in the LMS producing the Royal Scots.
As in 1925 the LNER already had 50 A1s there was no need immediate need, it is however interesting that no further pacifics were built until after the long travel valve gear issue had been addressed.
So where does this lead? It may have been the case that if Bert Spencer's revised valve gear had not proved so successful that the A3 class may not have been built and a large 4-6-0 substituted. I believe that to this points to a mid 1920s time frame for the original proposal.

[Nova]

The proposed 4-6-0 was described in some accounts as a "Super 'Sandringham' ", but actually it could better be called a shortened Pacific.

from that description I'm picturing a hybrid between the A1/A3 and the Sandringham. From the back of the boiler forward resembling a Pacific with a conical boiler possibly the same size as the boiler used on the V2 but shotened by one "section" (that is to say the space between two boiler bands). With the waisted-firebox (enlangened if needs be), cab and wheel spacings of the Sandringham.

as is the norm I'm somewhat tempted to try to replicate it in model form using parts from a Bachmann V2 and a Hornby B17, better add that to my mile long list of future projects

[billbedford]

Then again, by this date the LNER and LMS were communicating on design matters, and Doncaster would have had a good idea of how the three cylinder 4-6-0 developments by Stanier's team were proceeding. It was observation of the Black five that guided the mixed traffic 4-6-0 that the LNER did design, acknowledged by Thompson in correspondence to Stanier.

...and we all know where the Black 5 came from, don't we?

Yep -- the Highland River.....

[billbedford]

Then again, by this date the LNER and LMS were communicating on design matters, and Doncaster would have had a good idea of how the three cylinder 4-6-0 developments by Stanier's team were proceeding. It was observation of the Black five that guided the mixed traffic 4-6-0 that the LNER did design, acknowledged by Thompson in correspondence to Stanier.

But the Royal Scots and the B17 had exactly the same 'engine', give or take half an inch on the cylinder diameter. Both were designed within a year by the same drawing office, i.e. NBL in Glasgow.

[Nova]

Whilst we have much of Doncaster influenced pacific in the design the cab also saws a Darlington influence.

like on the K3s?

[john coffin]

I wondered how long it would take for the myth that NBL designed the B17 to come forward yet again.

Whilst I also read the Green book 2B, I have found part of many conversations that were held between Maurice Boddy and Kenneth Leech
of which I have copies.

This is one part of many that I have access to.
"Thank you, that clears up that story**. Next question. What do you know about the myth (?) that Gresley handed over the task of designing the “Sandringham” Class 4-6-0 to N.B. Loco. Co. because his staff at Doncaster were beaten.
Gresley did not “hand over the problem” of the East Anglian motive power to the N.B. Loco. Co. I saw his proposed design before ever it was sent to the N.B. Loco. Co., and it was a better looking engine than a Sandringham, because N.B. extended the coupled wheelbase towards the rear and put the smokebox forward a bit – otherwise the Sandringhams were all Gresley."

Neither the Scots nor B17's were very successful straight out of the factory, the 17's particularly were bad steamers initially, and the Scots needed Stanier to sort them out.

paul