Churchward square shank carriage buffers - oval or round head

[Western Star]

This topic relates to the buffers fitted to GWR Toplights and 70' stock from build to circa 1914.

 

Photographs and other RM Web topics illustrate the square shank buffers as being fitted with either round heads or oval heads.  The Wild Swan book "Official Drawings No.3 Great Western Coaches" includes drawings of Toplight, Dreadnought and Concertina coaches which show that those coaches were built with oval head buffers...  yet photos of those coaches later in life (say 1940s) show the carriages were fitted with round head buffers at some time after building.

 

When did Swindon change from oval-head to round-head for new build coaches?

 

When did Swindon start changing oval buffers to round buffers during repairs / maintenance?

 

If diagram is important, initially I am interested in the F16 slip, the K18 brake van, the E77 compo and the D42 brake third.

 

thank you and regards, Graham

[Miss Prism]

The change was probably an early Collett-ism, but I can't date it.

 

Large heads were often bolt-ons to smaller ones, so could be upgraded fairly easily.

[Il Grifone]

From what I've seen from photos, new build started in the twenties and refits in the thirties, probably when the buffer faces were worn. As always a photo is the best bet.

[Miss Prism]

I can imagine a few heads got cracked or bent in heavy shunts, but did buffer faces get worn?

[Il Grifone]

I can imagine a few heads got cracked or bent in heavy shunts, but did buffer faces get worn?

 

They would rub against each other on every curve, but how severe the wear would be I don't know. It would depend on how well they were greased. Wear or physical damage would really be the only reason for their replacement and probably the reason for the redesign. It can't just have been that C.B.C. thought round looked better than elliptical. (IMHO the contrary is the case*.) The use of more expensive metal would have had to be justified to the board of directors. British Railways went back to elliptical with the MK I corridor carriages (non corridors had round buffers) where any wear would have been much less thanks to the use of buck-eye couplings.

 

* It would have saved me filing lots of  K's round buffer heads elliptical in my youth. (The oval ones are the wrong shape.)

 

I.ll have to see if my library has anything to say on the matter, when I can get to it again!

 

EDIT (for poor memory - the ones I remember were ex-GWR - and reliance on small indistinct photos)

 

BR Mk I non-corridor coaches had elliptical buffers, but DMUs were fitted with round ones.

Edited November 19, 2018 by Il Grifone