Jump to content

JimC

Members
  • Content Count

    380
  • Joined

  • Last visited

Community Reputation

293 Good

Contact Methods

  • Website URL
    http://www.devboats.co.uk/gwdrawings/

Recent Profile Visitors

226 profile views
  1. Isn't there a commercial model of Kerosene Castle being planned? That would be an obvious donor body shell for such a scheme.
  2. The fundamental problem with putting outside Walschaerts on the Stars is that there's nowhere to put a rocker to drive the inside valves. With the inside gear the rocker is located ahead of the outside cylinders to drive them from the front. Locating the rocker the other side of the cylinder from the valve gear and trying to make allowances for expansion does not seem like the sort of thing Churchward would have found satisfactory.
  3. Not really, the GWR design was very different and I believe rather more sophisticated. AIUI the MR design didn't have the "scissors" part which made for more even valve timing.
  4. I guess the question mark would be how well the GWR design would have survived LMS standards and practices of shed maintenance etc. Its documented that there were a number of GW specialities that didn't travel well. Would Castles have prospered in the "treat 'em rough" ethos of the ex LNWR sheds? GW locomotives benefited from high but expensive standards of maintenance and a definite esprit de corps that isn't always evident from loco crews of other lines, and one of the key attributes of a successful design is that it should fit well in the environment it finds itself in.
  5. Well then, it would be helpful if you were to say what the scholarly analysis concluded - especially if you are completely confident its free from the preconceptions and biases which are evident in the primary sources I've seen...
  6. My guess is that there was a lot of internal politics involved, and what the traffic department thought they were going to get was a nice safe copy of a known good design, but clearly that didn't happen. How much of it was a semi Lord Nelson copy, how much North British own design (presumably developed from export designs) and how much Derby is difficult to ascertain, because every commentator seems to reflect their own preconceptions/biases.
  7. I don't believe there were any GWR classes that didn't receive the shirtbutton. As you say, new and overhauled (=repainted) alike would received it. There's nothing I've seen which suggests there was any policy to prioritise different classes, though one may guess that older and absorbed stock that ran low mileages might be the longer survivors. Absorbed stock might not be branded at all.
  8. You're forgetting that Fowler's team already had a compound Pacific well progressed on the drawing board. Its probably a fair bet though, that like other early Pacifics, it wouldn't have been any more capable than a Castle.
  9. For sure. And everyone will have their own slant, some more credible than others. Its enough to say that under Collett the GWR was notably progressive in engineering matters, but less so in designing new locomotives.
  10. I guess as big an argument as anything against excess conservatism on the GWR is ATC. How many preventable accidents were there on other lines?
  11. The GWR for one. Felix Pole's (general manager of the GWR in the 1920s) book is full of the importance he places on what he calls (jarringly to modern ears) propaganda.
  12. All the railway companies suffered from a terrible complacency in some respects, different for each one. The trouble is unless we have the whole picture, maybe we don't have any. Collett, for example, would never have tolerated the level of big end failure that Gresley's team seemed unable to cure, and when the LNER big ends were finally sorted out it was with concepts that went back to Collett's work when King big end bearings were looking less than adequate in service. Gresley led a more innovative design team than Collett, but Collett led a better engineering team. High superheat is an odd one. Its such a top trumps figure. There's no doubt that high superheat brings greater efficiency, but it also comes with a price tag in increased oil consumption, wear and other disadvantages. Is anyone in a position to say where the business case lay? And at what date? I understand there was a big jump in lubrication technology in the 1930s. Its pretty well documented that Stanier introduced higher superheat on his early classes not for economy, but because his design team couldn't get the boilers to steam adequately without it. Its obvious that this was not a problem the GWR boilers suffered from, at least until coal supply intervened WW2 and after. But its possible to exaggerate coal supply too. When Castles embarrassed the local locomotives on the LNER and LMS they were using local coal, not Welsh. Doubtless it was top quality local coal, not the sort of low quality material that plagued post WW2 operation, but even so. One of the most interesting, perhaps, is boilers. There's an obvious difference in design philosophy between the north eastern stream of very large diameter parallel boilers with round top fireboxes and wide grates, cheaper and easier to construct, and the western philosophy of much more complex and expensive tapered boilers with narrow belpaire fireboxes. Both design schools had some practical experience of the other style, but a consensus was never reached. I wonder who was right? Can we ever know? Did it have anything to do with works capability rather than paper design? There was that lovely example in BR days when they established that machining costs at Works A were cheaper than Works B, and casting costs at Works B were cheaper than Works A. So they did the obvious thing, and got Works B to do the casting, and Works A to do the machining. End result - more expensive than either, since Works A's costs machining Works Bs castings were through the roof. And while the Cheltenham flyer was the Worlds fastest train, its also documented that the typical GWR service was a quick acceleration up to 60mph, then a gentle trundle along until it was time for the next station, where they'd probably spend about five minutes on the station work.
  13. That's the same photo that's in RCTS, but big enough to actually see!
  14. Photo G35 in RCTS part 7 shows 3306 Armorel with a standard 3 boiler, and you can definitely see that the smokebox is longer. The casing that covers the various pipes leading into the smokebox has moved back too. So although the differences are subtle, they are visible. The boiler cladding appears to me (although the background and small size of the photo doesn't make it easy to judge) to have the small parallel section at the front, its not a single cone of cladding like the 2251s etc. It surprises me that there aren't any enterprising souls 3d printing GW standard boilers sans fittings. I reckon you'd get a better result putting separate chimneys and safety valve covers on, and given a range of standard boilers all sorts of plastic bashing is made much easier.
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.