Talk:L&YR Class 31

Numbering
There is additional information about L&YR Class 30 and L&YR Class 31 at Locomotives of the Lancashire and Yorkshire Railway but it is unreferenced. There seems to have been some overlap between the two classes in terms of rebuilding and numbering. There also seems to have been a compound version. Can anyone clarify the situation? Biscuittin (talk) 08:55, 13 April 2012 (UTC)
 * See my comments at Talk:L&YR Class 30. -- Red rose64 (talk) 16:14, 14 April 2012 (UTC)

Class number
According to Casserley and Johnston, this was L&YR Class Q4. Biscuittin (talk) 18:44, 13 April 2012 (UTC)


 * Does anyone have an authoritative source for this whole "class 30" business? I can see it used in Casserley & Asher (I don't have Casserley & Johnston), but that's not a detailed ref, not a specific L&YR ref, and it's writing some time after the event.  Looking at better sources for L&YR locos specifically, I don't see this class numbering scheme being used.
 * In particular, did Aspinall, Hoy and Hughes all build "class 30"s of three different designs, or where they identified as different classes? Andy Dingley (talk) 19:57, 13 April 2012 (UTC)
 * I am trying to sort this out. See Talk:L&YR Class 30. Biscuittin (talk) 00:21, 14 April 2012 (UTC)
 * I think Class 30 and Class 31 were not official L&Y designations but just internal codes used by Rail UK, see and  Biscuittin (talk) 00:32, 14 April 2012 (UTC)
 * Revised opinion. Perhaps the L&Y had more than one classification system. My idea about Rail UK does not stand up in the case of L&YR Class 8. Rail UK calls it 5P-A Biscuittin (talk) 10:14, 14 April 2012 (UTC)
 * Classes 30 and 31 are verifiable, 30 being the saturated 0-8-0 and 31 the superheated 0-8-0, see
 * Marshall gives his source thus: "(From working timetable appendix 1921)". I would say that this means that they are official, even if used for a few years only.
 * By contrast, the letter/number codes like Q1 etc. are not official - see my comments at User talk:Biscuittin. -- Red rose64 (talk) 16:21, 14 April 2012 (UTC)
 * By contrast, the letter/number codes like Q1 etc. are not official - see my comments at User talk:Biscuittin. -- Red rose64 (talk) 16:21, 14 April 2012 (UTC)

Boiler diameter
These locos have the biggest boiler diameter I have ever seen on a British loco (look at the narrowness of the cab spectacles). Does anyone know the diameter? It may be an optical illusion, accentuated by the small diameter of the driving wheels. The locos are also relatively light at 66 tons, giving an axle load of less than 17 tons. Biscuittin (talk) 19:57, 29 December 2014 (UTC)
 * Marshall (see previous section) is curiously silent on the boiler dimensions for the superheated 0-8-0s, giving (p. 187) only the number of tubes, flues and heating surfaces for various types of superheater. Of the saturated types, he quotes (p. 150) a diameter of 4 ft 10 in for the normal and compound varieties, and 5 ft $5 1/4$ in for the Hoy corrugated firebox variant. He states (p. 182) that the 0-8-0 with large saturated boilers had the same size boiler as the 4-6-0; and (p. 180) that the 4-6-0 used the same flanging plates (i.e. were the same diameter) as the 0-8-2T; he gives (p. 141) 5 ft $8 1/4$ in as the diameter of the 4-6-0 boilers, and (p. 179) 5 ft $8 1/4$ in as the diameter of the 0-8-2T boilers. It's likely that the superheater 0-8-0 also used these flanging plates, so by a roundabout route I would suggest that the superheater 0-8-0 boilers were also 5 ft $8 1/4$ in diameter.
 * Marshall does give the axle loadings for the superheated 0-8-0s in working order, in ton-hundredweight-quarters from front to rear as 15-12-3; 17-8-2; 17-7-3; 15-15-0, total 66-4-0. -- Red rose64 (talk) 23:49, 29 December 2014 (UTC)
 * Thank you. Perhaps they are not the biggest. I think some NER locos had 6ft diameter boilers. The axle loadings are interesting because I thought 0-8-0s were usually nose-heavy. Biscuittin (talk) 11:03, 30 December 2014 (UTC)
 * I've found a book giving the actual boiler dimensions for the superheater 0-8-0 as 15 ft 0 in x 5 ft $8 1/4$ in:
 * The same size is given for the 4-6-0 (p. 92), the 4-6-4T (p. 94), the large-boiler saturated 0-8-0 (p. 95) and the same diameter (but 13 ft 0 in long) is given for the 0-8-2T (p. 99).
 * Some 0-8-0s were indeed nose-heavy (particularly when there are outside cylinders), which is why the LNWR rebuilt some of their Class B four-cylinder compounds to 2-8-0 Class E or Class F. The problem can also occur when a superheater is present, which is why the Great Central switched to the 2-8-0 wheel arrangement for the Class 8K. The LYR 0-8-0s were inside-cylinder, so the front axle could be set further forward in relation to the cylinders, which would aid weight distribution; careful setting of the springs could also transfer weight from the front. It's known that the LYR 2-4-2T with superheaters were also fitted with a ballast weight at the rear end, to counterbalance the superheater, so perhaps something similar was done with other superheated locos. -- Red rose64 (talk) 17:29, 30 December 2014 (UTC)
 * Some 0-8-0s were indeed nose-heavy (particularly when there are outside cylinders), which is why the LNWR rebuilt some of their Class B four-cylinder compounds to 2-8-0 Class E or Class F. The problem can also occur when a superheater is present, which is why the Great Central switched to the 2-8-0 wheel arrangement for the Class 8K. The LYR 0-8-0s were inside-cylinder, so the front axle could be set further forward in relation to the cylinders, which would aid weight distribution; careful setting of the springs could also transfer weight from the front. It's known that the LYR 2-4-2T with superheaters were also fitted with a ballast weight at the rear end, to counterbalance the superheater, so perhaps something similar was done with other superheated locos. -- Red rose64 (talk) 17:29, 30 December 2014 (UTC)

(From works drawings, the boiler diameter over the outside cladding was 6' 1" for the 4-6-0 Dreadnoughts, the o-8-2 tank engines (Class 32) and the large boiler 0-8-0, both saturated and super-heated. The 4-6-4 Baltic tank had the same boiler dimensions as the 4-6-0's) Ian Allen 17/11/2020.   — Preceding unsigned comment added by 91.125.4.189 (talk) 22:40, 17 November 2020 (UTC)
 * In the UK, boiler diameters were usually given over the outside of the largest ring, excluding cladding. -- Red rose64 &#x1f339; (talk) 23:47, 17 November 2020 (UTC)