Britannias - buffers

Discussion in 'Railtours & Preservation' started by alexl92, 7 Apr 2015.

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  1. alexl92

    alexl92 Established Member

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    Just seen an old photo of 70000 and 70013 side-by-side in 2010 at a gala. I noticed that one has round buffers on the front yet the other has oval buffers.

    Is there any reason why they'd be different? Is it a result of post-preservation restoration and limited availability of parts or were they built like that?
     
  2. colchesterken

    colchesterken Member

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    I bet that is how they were built. The preservation folk normally do their homework
     
  3. plastictaffy

    plastictaffy Established Member

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    So they'd be built like that because the stores at the works didn't have enough of one type??
     
  4. neilmc

    neilmc Member

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    As far as I know round buffers were the norm for the whole class, although 70045 Lord Rowallan was rebuilt with oval buffers after an accident and maintained these until being withdrawn as part of the final batch in December 1967.
     
  5. sprinterguy

    sprinterguy Established Member

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    Seems peculiar, as, based on the evidence of the many hundreds of photos of the two locos presented by a Google search, both locomotives sport round buffers.
     
  6. oddiesjack

    oddiesjack Member

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    I'm glad I'm not the only one to have done this and arrived at the same conclusion.

    It would help if the OP could indicate which loco had the oval buffers.
     
  7. Taunton

    Taunton Established Member

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    As I understand it (from a conversation with an engineer many years ago).

    Buffers are quite a heavy piece of steel, and have to take some considerable thumps of course. However they also need to hang off their internal springs/oleos, so you want to keep them relatively light to avoid overstressing these downwards, and therefore keep the buffer face relatively small.

    Against this is that if you make a circular buffer face too small you have the potential for "buffer lock", particularly on sharp reverse curves (eg over crossovers), where the buffers of the two adjacent vehicles manage to move out and then behind one another, and as things straighten up the lighter of the vehicles can even be twisted into derailment. Therefore a horizontally-oval buffer shape tries to meet both requirements. Getting vertical buffer lock is less likely, although not unknown.

    Tenders of steam locomotives were particularly prone to this because of the considerable difference in their weight between being loaded and empty, and therefore their relative height due to their springing (I know anyone who has stepped back from the footplate to the tender when at speed might deny that the tender has any springs ...)
     
  8. Clarence Yard

    Clarence Yard Member

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    70000 and 70013 side by side at a gala in 2010? Are you sure it wasn't 71000 and 70013 side by side? That would explain the oval buffers.

    Also I thought 70000 was still in bits then.
     
  9. alexl92

    alexl92 Established Member

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    Just been back and found the pic - you're absolutely right. My apologies.
     
  10. Clarence Yard

    Clarence Yard Member

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    No worries, mate. Query sorted!

    71000 is some piece of kit. I've been behind it twice on the main line and it has superb acceleration as well as being a really efficient steam producer. I hope they get it back working before too long.
     
  11. alexl92

    alexl92 Established Member

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    I know. I've never really been that gripped by the BR Standards in the same was as by, say a Big Lizzie or an A4, but 71000 intrigues me. I'd love to take a ride behind it some day, especially if the owning group manage to do everything that they want to with it.
     
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