JimC

I tried shortening the boiler on your photo hack by moving the driving wheels together and bringing the bogie back, then I had to move the outside cylinder drive to the middle drivers to not have excess angulation, and now, where's the middle cylinder, it will have to be divided drive like a de Glehn, and the cylinder forward of the smoke box, perhaps the smokebox could be longer and oh, the connecting rods are really too long, perhaps the cylinders need to move back like a de Glehn, the boiler needs to pitch higher to make room for the cylinder and oh good grief, its not easy this imaginary locomotive lark is it. I give up!

Thanks. I've been drawing a lot of GW classes over the last few years [shameless plug of shameless plug in sig!] and I hope I'm getting something of a picture of how the kit of parts could be assembled. I'm not enough of a steam engineer to be able to do the maths, but my best guess is that a Manor based 4-6-2T *might* just be feasible within the red route weight limits, whereas I'm quite sure that anything using the bigger Standard 1 boiler would be too heavy. Interestingly if one really wanted a mega GWR tank engine I suspect a Star 4 cylinder front end might be just about feasible too, with the extra weight mainly on the front bogie. I've got a fair sized library of GWR components, and its fun to see how they might go together. The WSRs 9351 is an interesting application of the "kit of parts", and I would rather like to know what the weights are on that "fictional" locomotive, and thus whether a Std 2 boiler mogul might have made for the Duke(dog) replacement the GWR never got round to building for the Cambrian lines. When you think about it the Dukedog was the outcome of the same game that some of us are playing - Cook saying OK, I've got a Duke, which they need, but is clapped out, and a Bulldog, which they don't need but has a reasonable chassis. Supposing we...

A tank engine version of the GWR Manor class.

On tunnels and the Box tunnel sun myth, its worth noting that if you have a straight tunnel on a gradient so that it points above the horizon, and its aimed vaguely south of east or vaguely south of west, then its very unlikely that the sun won't shine straight through on one day or another. The sun crosses an awful lot of sky in the course of a year!

The 47s were limited to 60mph because they tended to "nose about" above that speed, Cook says, and he puts it down to the extra sideplay and inclined planes on the rear axle. The 28s didn't have that arrangement, having a shorter fixed wheelbase, so there's no reason to suppose they had a proportional limit.

I'm not at all sure about either of those often told stories. The Great Bear boiler was built with the same flanging plates and had the same diameters as the King boiler, yet had 6ft 8.5 wheels, so it seems unlikely that the loading gauge was the problem. The 'Bear's boiler was pitched at 9ft 0in, and the King boiler at 8ft 11.25, as was the 4700 boiler (also the same diameters). Cook (GWR works head under Collett, later WR CME) says that the driving wheel size change was decided very early in the design process for the King - they piloted it on a Castle with tyres turned down to just under scrapping thickness. He states that the TE was pushed to over 40,000 at Sir Felix Pole's request, but that this was done by boring the cylinders out 1/4 of an inch - effectively to first rebore. There's a strong suspicion that not every set of new King cylinders were taken out the last 1/4 of an inch - maybe even just the first set or first few. Reduced driving wheel size of express locomotives was of course a general trend from the late 19th C on. Naturally in service all cylinders would have been out to beyond 16.25 sooner or later, and all driving wheels would have been turned down to below 6ft 6in.

They didn't. Hawksworth never wanted to build a pacific. What seems to have happened is that the staff in the drawing office sketched out some ideas on their own account, and when Hawksworth found out he put a halt to it. Its ironic that 20 odd years before Hawksworth and Stanier had done some similar work on an idea for a compound version of a Castle, but when the took it to Collett he put a stop to it! I've heard it said that the main problem Bulleid had with the Merchant Navy was his workforce refusing to build anything which wasn't for the war effort. I don't know how much truth there is in that though.

http://www.conservancy.co.uk/assets/assets/HN11_apuldram.pdf

The coal capacity on the large prairies was 4 tons, as against 4.25 tons on Collett 3,000 gallon tenders. Like most larger GWR tank engines there was a water tank under the coal - look for the diagonal line of close spaced rivets on the bunker. So a 2-6-4 could have the same the same coal capacity as a small tender engine plus approaching the same amount of water. I agree the Std 4 boiler would be a more likely option. I suppose a Dapol City of Truro could donate one, although time has not been kind to the quality of the mouldings. An amusing option for a fictional large GWR tank engine would be a 4-6-2T based around the Manor chassis and boiler.

The 51s et al carried 2,000 gallons of water, as much as the BR 2-6-4Ts. So a 7200 style extended bunker on a 5101 or 3150 would probably give around 2,700 gallons of water, enough for quite considerable trips, so you'd be looking at doing long cross country routes. Are you planning the Standard 2 boiler like the 61s, or the larger diameter Standard 4 like the 72s and the 3150s?

If you assume and equivalent of the 30s Loan act then a policy of "electrify everything you possibly can and flog off everything beyond Exeter to the GWR" makes a good deal of sense. Especially if you can use the money from the GWR for more electrification. That then leaves one with the entertaining prospect of working out what the Swindon CME would have done when, like Jarvis, he had to sort out the Bulleid Pacifics. One may hypothesise that a Swindon CME might have been more inclined to have a go at sorting out the engineering so that the oil bath kept water out and oil in. Whether that was possible at the 1950s state of the art is an interesting question.

But incorrect livery for a passenger locomotive, which is what she is these days...

"I made a new boiler from laminated layers of 5mm styrene" I presume you don't mean five whole millimetres thick? I've had no luck at all trying to create barrels from styreme, but I tried rolling a long piece into several layers. You did it in separate layers did you?

Mmm, but AIUI vermilion was a rather expensive pigment back then. I really can't see that being used wholesale for wagon stock. Wholly uncomparable of course, but when I worked in the plastics industry in the 70s the cost of pigments was a serious consideration, and so, to a lesser extent, was the cost of colour matching, especially if, as occasionally happened, a colour match went catastrophically wrong and a new batch had to be started. I'd look for wagon paint to be both cheap and readily colour matched. Indeed it wouldn't surprise me if there were evidence they made wagon paint to a formula and accepted the inevitable variation in shade.

How many pictures have you got that show them without a tank on one side? I only have the RCTS books, and there are photos showing the air tanks on L side and r side, and I think piped as you note, and the only ones they show without an air tank are ex Russian Front. If there are few or no photos showing them without air tanks its a reasonable bet that there was an air tank on each side unless better information turns up.

It all depends what you call a Churchward tender I suppose. Lot A51 (1509-1518) was built in 1901, and according to the drawings list most of the components had been designed in the 1890s, so might be better described as Dean. 1539 and 1560 were nominally built while Churchward was in charge, but were essentially using the same drawings. TBH I think putting CME names against tenders is rather notional. I find it hard to believe that Churchward's involvement in tender design went much beyond 'too many bl**dy frames are breaking: design some better ones'. Looking at the drawings list the Dean/Churchward 4,000 gallon tenders look to have been fundamentally the same chassis as the Dean 3,000 gallon ones and the early Churchward 3,500s. They look to have been built with something different in the water pickup gear, because the drawing number is different and there's a note in the book saying "converted to hand gear now". Exactly what frames they would have had in the 1930s though: a lot of those frames did get replaced, and you'd think the tenders with the heaviest load would break most often. The tender article in Pannier in 2003 says that 1560 at least received Collett era frames at some stage. I've just seen a photo of 1560 in RCTS part 12 (M16) dated 1952 attached to 2938, and not only does it have 1931 style Collett frames, it also has a Collett style fender running right round it. Only the front corner of the sides and the handrail arrangement looks like the earlier design.

> I don't have the correct drawings for the axleboxes yet so I'm having to make do with what I have in my library Axlebox drawings were: 12504 for most lots from A6-A91 47737 for lots A92 - A142 111273 for lots A145- A192 So your axleboxes would most likely be 47737 or 111273 after 1937.

I would say that those are post 1931 design frames - at least the design as used from 1931 on new tenders - which were often fitted to earlier tenders.

I think the identification of the 'intermediate' tender with Lot A112 in Pannier is over simplistic. I've spent a reasonable amount of time studying this, but its really hard to draw any firm conclusions. There are two features normally called intermediate, high sides and scalloped frames, but neither seems exclusive to lot A112. One of the odd things about the high sides is that they don't seem to be shown in any GA drawings I have traced, nor recorded in the Tender Lot record book. The GA drawing for lot 112 shows the standard lower sides. Its confusing, as some do, to call them Churchward Intermediate tenders, since they were built several years after GJC retired. I have found 1920s and 1930s vintage photos of the high sided variant on tenders with the earlier style frames, so before lot A112, so it seems most likely they were fitted on some new tenders before lot A112. They seem to have been originally run with rebuilt Stars and Castles, but later on these received 4,000 gallon tenders so the high sides were seen on other classes. Presumably they were not replaced, since the surviving lot A112 tender has low sides and a replacement tank. The scalloped frames, as noted above, are also not limited to lot A112 as I've seen a photo of 3,000 gallon tender with these frames. There is a note written in the Tender record book saying that lot 112 was built with high sides, and this isn't mentioned against other lots, but when you examine the writing and other entries it seems pretty clear this was written in several years later and is not contemporary with the tender construction. The whole thing is a minefield for modellers, because if you go through the drawings numbers in the record book its clear that there was never a clean sheet redesign of tenders after 1884. There were always some drawings - and thus parts designs - reused from previous designs. This means it was always possible to repair tenders with later parts, especially if new or heavily altered frames were fitted. Even the late slab sided tenders have a fair number of suspension components in common with the design that preceded them. So on the one hand, if you want to model a specific prototype you do need a dated photograph. On the other hand if there are no dated photographs almost any combination of features seems to be possible!

Interesting about Gibson... while he was undoubtedly there and had the overalls as you might say, it seems to me that he needs to be read with a considerable pinch of salt handy. He definitely has a weakness for these tales of coverups and conspiracies, and one suspects that sometimes it was more of a matter of no-one wanting to talk about errors any more than I like to recall any errors I might have made in my working life. As an example, if you go through his details about the King dimensions, the numbers simply do not add up to what he says they do. The same is also true of some of his "should have builts", again often his concept simply wouldn't have made the weight restrictions. Your analysis re valve gear and wheel spacing appears to me very well observed. I suppose the thinking was that as long as its got 19.5 tons (or whatever Dean's limit was) on the driving wheels it will have the same traction whether its towing a bogie or a tender behind, which is logical enough until the water tanks are nearly empty!

This is from their website. http://5at.co.uk/ind...innovation.html I hold no particular opinions about the project, for or against, but you don't seem to me to be representing what they say about their project. On the other hand the fascination so many have with the hopeless/hapless Leader thing bemuses me.

Ye gods, some of this stuff is a bit condescending isn't it? I'm sure it will come as a big suprise to the accountants of the preserved lines that they don't run revenue earning trains: to my uneducated eyes it appears to me that they do a damn sight better job of earning revenue than their predecessors did with those facilities. And its interesting to hear that all the advertising and other hard work that the Big 4 (especially the GW) put in on building tourist traffic wasn't running a proper railway either: one suspects there are a few past managers sniggering in their graves at that... I used to live close to Tattenham corner station where the SECR and Southern put an awful lot of investment into Leisure traffic: was that not running a "proper" railway either? Its something I've observed in sports where I've had a far more active role than I have with railways, 4mm or 305mm to the foot: scorn and vitriol is most common between people who are involved in related but not identical activiies. Its rarely productive or useful and neither branch seems to gain from it... The preserved lines are often economically important in their local areas, and even when they are primarily volunteer run still make a significant contribution to the economy and to employment at service companies. Sneering at them seems counter productive for all of us.

Three in fact. But Churchward hd his eyes open far wider than that... You could argue that the Saints had American boilers and cylinders on Prussian inspired frames and superheat, (plus native valve gear) and the Stars added French bogies, divided drive and inside big end design. The great man wasn't so much an innovator as an integrator, being able to see the best available practice from all sorts of sources and bring them together to create a harmonious whole that was even more than the sum of its parts. I suspect most really competent engineers will tell you that such is a rather greater achievement than coming up with a whole bunch of new ideas, some of which work and some of which don't.

Here's a slightly different scale of what-if, and a very cruel camera. First time I've tried doing anything like that but far too much room for improvement. Maybe paint will help.