Mk1 Resources And Parts

Discussion in 'Coaching stock' started by 28ten, 27 October 2012.

  1. Bob Reid

    Bob Reid Western Thunderer

    Now Graham, if we could only get wheel centres with the profile shown on the back and the front, I'd have them with or without the four holes. :)
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  2. Dog Star

    Dog Star Western Thunderer

    Mk.1 carriages ran on different types of bogies over the years... BR standard, Commonwealth and B4.... with some carriages changing bogie type during a works repair. Just how interchangeable were the bogies for any given carriage? What underframe modifications were necessary to make a change of bogie type?

    For example:- could a carriage built with CW be changed to B4 and then back to CW?

    One bogie change which interests me is BR (equalised brake gear) to B4... easy or needs the modelling toolbox?

    Oh, go on then. BR (unequalised brake gear) to CW or B4.

    Thanks, Graham
  3. Bob Reid

    Bob Reid Western Thunderer

    There's nothing like a straightforward question Graham - your right Bob - That's nothing like a straightforward question ;) I'll have to go and have a lie down before answering that one...!
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  4. Dog Star

    Dog Star Western Thunderer

    Why me? Why cannot someone else ask the tricky Questions?

    Your right Bob - that is nothing like a simples question :rolleyes: . I did have to lie down and think through the questions before I wrote the post :confused: .

    In passing Bob, this is a simple question and one to which an answer is eluding me at the moment... where can I find a SL/SW dwg for a Western wheel/wheelset?

    regards, Graham
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  5. Bob Reid

    Bob Reid Western Thunderer

    Have you tried the NRM? Unfortunately though it would mean a trip for much of what came out of Swindon is still being catalogued at the moment (according to the website anyway) and not available online. Failing that how about asking on the Western Locomotive Association forum?
  6. Dog Star

    Dog Star Western Thunderer

    Tried the obvious... and we are talking about a class which became extinct in 1977 as far as the railway workshops were concerned.
  7. Bob Reid

    Bob Reid Western Thunderer

    Thinking about this Graham, I'm not sure there is an easy answer. Once they'd been converted to CW or B4/B5 bogies they were never done with backward compatibility in mind, each bogie change requiring alterations - some minor, some not so to the underframe and brakegear that in theory would need to be undone. Unfortunately listing all of the changes that happened or were required would take far to long for me to make a stab at describing - and would need a a chapter in their own right to describe. As far as modelling goes - with the exception of the Brakework changes - none of them would be particularly noticeable to a modeller - unless you were quite good at spotting different centre castings in 7mm scale (in-situ)!
  8. Dog Star

    Dog Star Western Thunderer

    Ok, simples is as simples does.... and there is no such thing as a simple question when discussing the design evolution of the Mk.1 underframe. The original intention was to try to ask about how the underframe design changed as the carriages moved from BR1 to CW to B4 bogie types - a PM exchange between Bob and myself has given me a better understanding of why such a simple question can be answered only by a three volume novel.

    If most WTers are modellers, rather than engineers or preservationists, then the original post can be constrained to a smaller field of interest, for example:-

    "for a 7mm model of a Mk.1 carriage, what differences might be visible on a model with "vacuum cylinder outside" of the brake cross-shaft compared to a model with "vacuum cylinder inside" of the brake cross-shaft?".

    Bob has indicated that such a question could be dealt with as a separate post, linked to this topic, and with the idea of outlining the different brake arrangements used across the range of Mk.1 coaches (including the hand brake fittings).

    Apart from Bob, Heather and I, who might be interested in such a posting?

    regards, Graham
  9. Dog Star

    Dog Star Western Thunderer

    Way back when, in this post, Bob kind of challenged the WT world by suggesting that the odds were heavily against finding an exception to the "norm" in regard to Mk.1 brake gear arrangements, viz:-

    * symmetric V-hanger, vacuum cylinder inside of cross-shaft, un-equalised brake gear version of standard BR bogie;
    * assymmetric V-hanger, vacuum cylinder outside of cross-shaft, equalised brake gear bogie (could be BR1, CW or B4).

    Well, looks like Bob might have found an exception. This Wiki page details some of the preserved Mk.1 TPO sorting carriages and at least W80349 seems to be an exception to the rule.

    regards, Graham
  10. Steph Dale

    Steph Dale Western Thunderer

    Well me; even if only from an academic viewpoint as someone who has an interest in carriages and engineering. And that's despite me thinking that because of its ubiquity the Mk1 is probably the most boring carriage we've ever had in the UK...

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  11. djparkins

    djparkins Western Thunderer

    No No No! To paraphrase George Orwell - Underframe & Solebars Good! Integral Design Bad!
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  12. Steph Dale

    Steph Dale Western Thunderer

    Can't really argue with that - Maunsell SECR and SR stock is my 'thing'...

  13. Dog Star

    Dog Star Western Thunderer

    You are a real heathen... the Mk.1 concept is a magic piece of engineering for its day / purpose / construction (and other -ologies). The Mk.1 carriage is as much a work of art as the Routemaster, the Landie, the Comet and other pieces of English engineeering.

    You are hereby sentenced to the construction of 7mm models of Mr. and Mrs. Kruger (in S7 of course, with split axles and full motion) ;) .
  14. Heather Kay

    Heather Kay Western Thunderer

    Hear hear! :thumbs:
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  15. Dog Star

    Dog Star Western Thunderer

    Seems that I had overlooked Rule 4 which Bob says goes something like this:-

    "Whatever you thought, believed or dreamt before about the Mk.1 underframe - TPO carriages do something different."

    Never mind, just have a gander at this pikkie and savour the confusion surrounding the brake gear... and then marvel at the nose-hung generator hung off of the bogie headstocks. Ponder anew and start saving the pennies, this is a beautiful beastie.
  16. Bob Reid

    Bob Reid Western Thunderer

    Not only did we have a multitude of builders - BR & Private building vehicles over a 14+ year period, but a mass of Experiments & Modifications to the "standard" over an awful lot longer is it any wonder that for every rule there's an exception - or three! With passenger stock it's bad enough but TPO's are about the worst case scenario Graham - so many variations on but two basic types of Sorting & Stowage van - some built from new, some converted from earlier passenger stock vehicles, with or without nets or arms, with arm but no nets, with the provision for nets but never fitted.... and so on. Fortunately Graham - you can count that TPO Brake arrangement as just one of those oddities!
  17. Dog Star

    Dog Star Western Thunderer

    Six months later I returned to the NRM and "Valiant" was outside the Great Hall, photos duly taken. The carriage does not carry any identification other than a builder's plate, here:-


    I shall process the photos of the underframe fittings today. Suffice to say for now that this BG is dual heat and dual brake... running on CWs with the pull-rod going under the axle and picking up on the bottom of the fulcrum levers (which might / might not be correct for a CW bogie).

    regards, Graham
  18. Dog Star

    Dog Star Western Thunderer

    The first photos to tempt you...



    These are a starter for ten... the next post is going to need paracetemol.
  19. Dog Star

    Dog Star Western Thunderer

    Comments, questions and captions are all welcome here.

    Surprising just how many of the brake levers have holes without pins... not sure if the unused holes are for adjustment or are redundant in this application, possibly because of component re-use in an in-appropriate manner.

    regards, Graham
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  20. Bob Reid

    Bob Reid Western Thunderer

    81025 (Valiant) lasted almost all its life with BR Bogies - not sure when the CW bogies were fitted to it i.e. whether they were done since its withdrawal from the (BR) Revenue Earning fleet - one thing's for sure that's a real bastardisation of the "usual" brake arrangements - including where that Air Brake Cylinder is sitting! The Brake Pull Rod running under the bogie has been re-used from the earlier non-compensated/equalised bogie - it was normally replaced with one not requiring the multiple hole adjusters - that was done on the bogie brakegear.