I recently completed an ambitious build that had been in my 'want to do one day' list for quite a while, one of the GWR's briefly considered but never built 8000 series 'Cathedral' Class Pacifics. The original never progressed beyond preliminary sketches on the drawing board before it was abandoned. There is very little factual detail about this project, whether Hawksworth originated the idea or he was simply the one who ordered that work cease when he heard of it is not actually known. There are no official drawings left and only two artist's impressions from books and a good stab at a line drawing on line. However, a very small number of models have been built, all slightly different in detail, and so no-one can say with certainty that any of them are inaccurate. Or accurate....
This is my finished attempt [note that it still awaits the two red dot route classification on the cab side sheets] and there's a link to the description of the build for any who are interested. It took a couple of hours a night for two months from start to finish and is as close to the chosen illustration as I was able to get.
Looks neat overall. One aspect that you might want to think about, the outside axle box on the leading bogie wheel. The design problem that led to this arrangement had been solved pretty much as erection of the King class ended. The pacific would have had a regular inside axlebox bogie, based on what evidence is available.
There is a view that had the beast been built, it would probably have been fitted with the improved Castle front bogie because, as you have noted, the actual cause of the problem which led to the King’s bogie being rebuilt and somewhat over-engineered had later been more accurately understood.
However, I kept with the King’s bogie as that is what would have been included in the initial specifications had they actually seen the light of day. That, and the fact that I didn’t have a spare Castle bogie knocking around and I’d spent quite enough on this project already!
Tony
Men with false teeth may yet speak the truth.......
Sort of reminds me of The Great Bear which was eventually abandoned through being too big to negotiate certain track formations not that they didn't try. I can't remember where it derailed, but it was said to be due to its size. (It wasn't that it was a 4-6-2. It was more that it was a very large 4-6-2 as I understand it?)
Part of the main reason why the GWR didn't bother with a 4-6-2 wheel arrangement was that a 4-6-0 can be made to give greater tractive effort on the rails for its size than a 4-6-2. The reason why the other companies needed to run 4-6-2's was a very real one. The other companies could not guarantee access to good quality anthracite coal so needed much larger ashpans, hence the need to build greater length locos and the extra pair of pony wheels to support them. The GWR had guaranteed access to top quality anthracite which is why they never bothered with large fire grates.
The other elemsnt which distuinguishes a GWR loco compared to other companies locos (Apart from the company favouring internal walschaerts valve gear and tapered "Canadian" boilers as a safety feature to prevent boiler explosions if the loco hits a snowdrift.. GWR directors went to Canada to see the then new design and were quick to adapted them), were that the GWR experimented with walschaerts valve ear and changed the angle by five degress so instead of a 70 degree angle that all other companies used, the GWR adopted a 65 degree angle, which gave their engines vastly improved power output per their size and they also used less coal! One can easily hear the difference in sound between a GWR designed loco and a loco from another company, as due 5° difference in valve gear angle, GWR locos had a much stronger chimney blast noise so they sounded more "Throaty" than other engines.
I believe the reason why the 4-6-2 design did not get past a few drawings with the exception of the early years when they built "The Great Bear", was that apart from not needing a larger ashpan, when one reads the many accounts from experienced traincrew from the past who regularly worked with Castles and Kings, was they they said the Castles were the better locos, and used less coal as well, with only a few mph difference in their top speed (Castles regularly hit 109mph flat out where Kings were regularly hitting 112mph while in daily service), and traincrew found they needed to work harder (Especially firemen) when they had a King due to its larger boiler, while the Castles were said to have a more perfect match of boiler size to feed the cylinders for the job at hand, so the traincrew had less work to do when running them to keep to time. (Only top link traincrew from certain depots were ever allowed to work the Kings. They kept building Castles well into B.R. days (Think up to 1958? Can't remember) where they only ever made 30 Kings. The other downside of Kings is their size (Mainly boiler and chimney height) meant they could only be used on double red mainline routes, where castles could be used on other routes (They were red routes), though still were limited.
The first time a King class ever went west of Swansea was in 1985, on the GWR 150 celebrations (No.6000, King George V) and I remember being told that a few local people found out that the King class was coming down the line to test clearances two weeks prior to the celebrations. One of the tight spots was at Pembrey & Burry Port station as they were concerned about the road overbridge and the platforms (Don't know why the platforms as there is a decent gap, and also, as the station was built for broad gauge, there is a larger than normal gap between the two tracks. (About 10ft rather than the usual 6ft). But I remember Mr James the taxi driver (Also drove minibuses and was the local undertaker and had previously owned a bus company) tell me that he was one who was on the down platform when the King was sent to test for clerances. He said they watched the loco in the distance, so were getting ready, and as it came closer, someone said "Isn't it coming a bit fast?"
They waited and as it got closer they realized they were coming through at a speed close to 70+mph! The guy who told me said that someone he knew jumped over the station wall and others were running for cover. It was really close as there wasn't much gap going under that bridge!
Around a decade or two later one of the preserved King classes on a steam special should have been running on one of the main lines in the Reading area or between Reading and London Pad? and was diverted into a loop to allow another service to pass. Unknown to the traincrew and the signalman the loop didn't have sufficient height with an overbridge and it took the Kings safety valve clean off. I was working on the railway at the time, so we heard the goings on. Not sure which King it was. (King George V was off the rails by then needing work on her boiler).
Looking at your excellent model. I can see Princess in there? I wonder how many at the club will be wondering what it is when you let it run? Never forget in my teens I saw photos of a class 45 with the axleboxes painted white. (I thought they were white). So I painted my Mainline class 45's axleboxes white. I ran it on the Clubs layout in Carmarthen (Carmarthen & West Wales Railway Society) and someone who was watching my loco said "Shouldn't they be yellow?" It was then I realized I had seen a black ad white photo. We didn't knkw if they were white or yellow, but rhey looked great white, so white they were!
Thanks for your interesting comment Mountain. The link to the build blog shows that there is indeed a Princess boiler and rear truck lurking, very heavily adapted, in there.
The few illustrations of the 8000 series show the influence of the Princess Pacific design on this project, something confirmed by OS Nock.
The Great Bear was, as you said, a one-off. Built in ‘08, it was withdrawn in ‘24 for two main reasons: it required a major re-build at that time and the Board was not prepared to sanction such considerable expenditure on a distinctly non-standard project and, by that time, The Bear had become totally out-classed by the magnificent Castles, which were more powerful, more efficient and, of course, a standard class. It was thus no coincidence that The Bear became Viscount Churchill, a Castle, on rebuilding.
Tony
Men with false teeth may yet speak the truth.......
Now you have regained your breath from building your 'Neverwazza', there is now a suitable RTR OO mechanism for M. Chapelon's favoured thought on where Swindon might go next in maximum power steam. Take a Hornby P2 mechanism, and adapt it for a 4-8-0...
It has been suggested that this one might have been less prone to slipping than a powerful, larger-wheeled 4-6-0 might have been, and it would probably have managed the Devon Banks more efficiently. But we’ll never know of course.
I prefer the aesthetics of the 4-6-0 however. I think that a GWR 4-8-0 just looks too ‘freight’!
Anyway, I’m back to coaches now, there’s a big backlog to finish, including my miner’s train, a 6-wheel Family Saloon, a B-Set pair, a Slip Coach and whatever else jumps into my mind as a distraction in between. And something will!
Tony
Men with false teeth may yet speak the truth.......
Not quite what M. Chapelon had in mind! His 4-8-0 developed the highest specific power output measured from a steam loco. Naturally it was a compound, with what looked like most of the plumbing on the outside, somewhat different from Swindon's loco styling tradition post Brunel.
If you have never looked at it before bung 'sncf chapelon 240p' in your favoured search engine. That would have eaten the Devon banks for breakfast.
Slip coaches are interesting! Often thought DCC could be used to operate a slip. One would need heavy wheels such as Romfords and some nice bearings for free running. Would be interesting!
Such a beastie would have been allowed through to Chester on the Birkenhead expresses - as the axle weight loading would have been more evenly spread.. (Kings were banned from Chester due to a bridge at Saltney (just west of Chester), but shock horror the GWR permanent way supremos had got it wrong and so when BR re-tested and re-calibrated the measurements in the 1970s - I was able to see KGV no 6000 and Princess Elizabeth working into Chester in 1977 !!). A blissful day that cemented my love of steam.
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