Jump to content
 

Mk.1 BTK / BSK prototype M 34000 / M 34095 and L.M.S. lot 1626


HGR
 Share

Recommended Posts

L.M.S. lot 1626 was attributed to an all-steel brake third corridor BTK for experimental purposes.

Listed as built Derby 1950.

 

B.R. lot 30003 was for qty. 95 Mk.1 BTK nos. M 34000 to 34094 (mostly for LMR but a few ER ones in there as well). These have Derby build dates from late 1950 through into 1952.

 

The prototype Mk.1 all-steel standard coaches displayed to the B.R.B. top brass in 1950 were CK no. S 15000 and BTK no. M 34000

 

The next batch of BTKs from Derby, also part of the 1951 building programme continued on with lot 30025 as numbers M 34095 - SC 34224 (with batches for WR, SR and ER in amongst). M34095 has a build date 1952 following on from those of the prior lot above, and the rest of this lot follow on from that.

 

The question then : was the vehicle of L.M.S. lot 1626 actually M 34000 ? Later information in numerous sources says this vehicle is M 34095 and was subsequently included with the vehicles of lot 30025 ?

 

 

As an aside ... does anyone know what was attributed to the cancelled lot 30024 please ?

 

 

Link to post
Share on other sites

To answer your question, I don't think M34000 was the experimental vehicle built under LMS lot 1626. My best guess is that it was an incomplete vehicle not intended for service. However when it's experimental use was over, it was not wasted but used to make a production BTK in 1952 (M34095). Likewise S15000 was built as a demonstrator with both open seating and compartments and never entered service as such. It was rebuilt into something more like a more standard CK in 1952 but retained uneven compartment widths.

 

There is evidence that LMS lots 1627 and 1630 were attributed to Mk1 CK & BTK respectively.

Link to post
Share on other sites

All listings I have seen have 34095 as the prototype. The fact that it was initially to a LMS lot probably meant than it was likely considered in that number series (although 34000 would be a BG).  Since lot 30001- 026 were ordered on 14th December 1950 and the prototypes were already in existence I would suggest that there was a clerical error and it had to be tacked on after lot 30003. I take it from a combination of Parkin and others that a photo of '34000' with the number on the left is actually 34095. If it is on the right it is the real '34000'. See Parkin photo on page 46 (prototype 34000 dated 1950) and page 77 (production 34000)

 

'34000' lasted to February 1994 as carflat B745247, there may be photos of if as it lasted that long. The prototypes had a different design of underframe which should be clearly visible on a carflat conversion.

 

34095 was absorbed into lot 30025 which was a Wolverton lot, not a Derby one - it would be interesting to know what the builders plate said.

 

Lot 30024 was between the second lot of BG and the third lot of BTK. Given lot 30027 was bumped to 10th May 1952 along with 30052 (FKs 13060-13064 and 13033-035) so lot 30024 could be a cancelled FK order. There are no other obvious gaps so 30024 may have been for a second lot of something which was no loner needed, RFO?

 

 

 

 

 

 

Link to post
Share on other sites

I would think the reason an LMS lot number was used for the prototype was that the first BR lot numbers weren't issued until 12/50.

 

Bob Reid of this parish has previously sent me a list of early Mk1 wiring drawings he has access to. I hope he doesn't mind me copying the list here. As you can see there are 2 other LMS lot numbers mentioned. The Type A etc was an early form of classification - see Parkin appendix 2a.

 

Drg SC/DE/44853  Standard Coach - Wiring Diagram - Corridor First Type 'A' (17/4/50)
Drg SC/DE/44854  Standard Coach - Wiring Diagram - Corridor Composite Type 'B' - Lot No.1627 (12/4/50)
Drg SC/DE/44855  Standard Coach - Wiring Diagram - Corridor Brake Third Type 'E' - Lot No.1626 & 1630 (22/4/50)
Drg SC/DE/44856  Standard Coach - Wiring Diagram - Open Cars Types 'G' & 'H' (12/6/50)
Drg SC/DE/44858  Standard Coach - Wiring Diagram - Open Cars Types 'J' & 'K' (7/7/50)
Drg SC/DE/44860  Standard Coach - Wiring Diagram - Corridor Third Type 'C' (23/6/50)
Drg SC/DE/44861  Standard Coach - Wiring Diagram - Corridor Brake Composite Type 'D' (28/4/50)
Drg SC/DE/44909  Standard Coach - Wiring Diagram - 58ft Brake Van (5/7/50)

 

 

Link to post
Share on other sites

59 minutes ago, mark54 said:

I would think the reason an LMS lot number was used for the prototype was that the first BR lot numbers weren't issued until 12/50.

 

As I pointed out the first three coaches were built before the BR lot numbering started - 14th December as per Peter Hall. For the SK and CK, the coaches were incorporated into the BR numbering system and subsequent coaches carried on the numbering system. This did not happen for the BTK so the first production coach was a duplicate '34000'. This was almost certainly an error; but it is is still obvious as 34095 (Built Derby) was merged with Wolverton built lot.

 

It is interesting that after CK 15000 was built next one delivered was 15021 which was seen before the end of 1950 (15001-15020 wasn't built until 1952/53).     

Link to post
Share on other sites

Thank you all for the replies so far. Some interesting info.

 

To raise some further questions & answers, please :

 

Far as I know only the Eastleigh prototype CK  S 15000 had the inward facing underframe angle-section trusses, everything else was made with them facing outwards. However to be fair, I don't ever remember seeing M 34000 in later years to have checked. The official B.R. Derby photo of M 34000, as printed in Parkin, isn't clear enough to definitely say which way the bottom angles face - in or out. Does anyone have an actual print of this photograph that could be given the once-over with the magnifier ? The lifting date painted on the solebar of 10-8-50 ties in with other contemporary info of this coach.

 

The left-hand number would be correct initially for 1950, but it migrated to the right fairly early in 1951, so as to be at the same corner as the dimensions plate on the coach end apparently. 

 

The first B.R. coaching stock lots issued in Dec. 1950 when the new 30001 series was introduced may well have included some vehicles or batches already allocated lot numbers in the series of the former companies. The same happened with wagon lots 2001 upwards which initially mopped up the order books of the former company's works of vehicles to their own designs prior to B.R. standard wagons. Lot 30001 was to convert the prototype CK into the all-compartment layout to diag. 127 (i.e. not for the original construction of the vehicle itself) - not sure what lot it was originally given, a Head Office Order (H.O.O.) number in 1950 ?

 

Does anyone have details of the vehicle number ranges or quantities attributed to L.M.S. lots 1626 - 1630 ?


A build programme, for example 1951 would be issued as a block of lots with intended types and quantity, to which the number ranges would be allocated. As would each region's needs. These would then be assigned to a particular works or outside contractor depending on their bids to tender and perceived capacity to fulfil the orders. Each works / builder would then set away manufacturing the vehicles in a series production-line style.

 

The appearance of Eastleigh production CKs 15021 upwards ahead of the lower numbered Derby batch probably more reflects Derby having the jigs set up for building TKs and BTKs, which they were cracking through at an impressive rate. If you look at the build dates per lot per works rather than per type, this is sometimes more evident. Same could happen with locos / wagons if construction was shared over multiple works / builders, and some were quicker at turning them out or more or less busy with other work. Sometimes materials, particularly steel shortages, would slow down production. This could result in orders being amended or curtailed, and possibly re-issued later on a different lot number - in some cases, multiple attempts.

 

Add to this that presumably there was scope for regions to expedite their allocations and thus upset the delivery sequence. Metro-Cammell seemed to be particularly adept at this. When building large lots of a particular vehicle type for a number of regions, there were in effect all of the regional series within the lot being released concurrently rather than in overall numerical order.

 

Beware that what's shown on the builder's worksplate sometimes can be misleading. Take for example the Swindon lot 30019 FKs 13033 - 13035 that got transferred to Eastleigh works on lot 30052 - these had Swindon builders plates like the rest of the lot 30019 vehicles.

 

Not sure what lot 30024 was intended to be, but I did wonder if lots 30025 and 30026 were tagged on to transfer production to other works with spare capacity. It gets messy after that as the 1952 programme was abandoned (steel shortage) and rolled on into the 1953 programme. There's a huge raft of subsequent order amendments amongst them. 

 

  • Informative/Useful 1
Link to post
Share on other sites

19 hours ago, Bomag said:

As I pointed out the first three coaches were built before the BR lot numbering started - 14th December as per Peter Hall. For the SK and CK, the coaches were incorporated into the BR numbering system and subsequent coaches carried on the numbering system. This did not happen for the BTK so the first production coach was a duplicate '34000'. This was almost certainly an error; but it is is still obvious as 34095 (Built Derby) was merged with Wolverton built lot.

 

It is interesting that after CK 15000 was built next one delivered was 15021 which was seen before the end of 1950 (15001-15020 wasn't built until 1952/53).     

So if I am understanding you right, you are saying there were 3 prototypes - BTK, CK & TK (presumably M24000)? This is the first time I've seen this mentioned anywhere that a TK was amongst the Mk1 prototypes. Do you have anything to support this?

Edited by mark54
Link to post
Share on other sites

According to several sources including Longworth the following were structurally completed by September 1950  - 15000, 15021, 24000 and 34095 (I had forgot about 15021 in my first post). Whether they were considered as prototypes, preproduction or test samples is not relevant, the point is that they were constructed (if not fully completed) before the ordering of the first Lot in the BR series.  See Parkin pages 81 and 82 for early photos of 24000 and 15021.

 

Given the propensity of the railways to swap vehicles identities from Silver Jubilee to D6123 it is perfectly possible that 34000/34095 identities were swapped in reality or equally it was a paper exercise and 34095 was identified as Lot 1626 to get the number right and it was in reality a production BTK.

Edited by Bomag
Link to post
Share on other sites

Something to be aware of with the dates quoted in Longworth - those shown alongside the individual vehicle number are the date it was first noted or reported in traffic. This ties in with contemporary sightings in the likes of Railway Observers of the time. This would of course always be some variable length of time after the vehicle officially left works and was delivered into traffic. In some cases early sightings were made of trains of newly outshopped vehicles fresh from main works or builder in transit to their allocated region. Some individual examples on the other hand seemed to find places to hide for numbers of months before being spotted in traffic, possibly remaining on works for trials or experimental purposes before being released, or otherwise simply just not being noted by observers of the day.

 

M 34095 is the oddity. Lot 1626 gives it a build date of 1950 along with the others mentioned above, but the first mention or sighting of this number is not until well into 1952 roughly in sequence with the appearance of the last examples of lot 30003 from Derby and the first ones of lot 30025 from Wolverton. In the meantime, Eastleigh had already set away turning out some of the higher numbered examples for the Eastern and Southern Regions. 

 

Link to post
Share on other sites

On 13/05/2021 at 00:14, HGR said:

Something to be aware of with the dates quoted in Longworth - those shown alongside the individual vehicle number are the date it was first noted or reported in traffic. This ties in with contemporary sightings in the likes of Railway Observers of the time. This would of course always be some variable length of time after the vehicle officially left works and was delivered into traffic. In some cases early sightings were made of trains of newly outshopped vehicles fresh from main works or builder in transit to their allocated region. Some individual examples on the other hand seemed to find places to hide for numbers of months before being spotted in traffic, possibly remaining on works for trials or experimental purposes before being released, or otherwise simply just not being noted by observers of the day.

 

M 34095 is the oddity. Lot 1626 gives it a build date of 1950 along with the others mentioned above, but the first mention or sighting of this number is not until well into 1952 roughly in sequence with the appearance of the last examples of lot 30003 from Derby and the first ones of lot 30025 from Wolverton. In the meantime, Eastleigh had already set away turning out some of the higher numbered examples for the Eastern and Southern Regions. 

 

To add to your comments, if they were completed in 9/50, that is 3 months before the issue of a lot number and 6 months before early production Mk1’s were displayed by the RE at Marylebone. I can no mention of them in the Parkin Supplement Carriage Standards Committee minutes before that date, only S15000 & M34000. It would be interesting to know where Longworth got the information from?

 

With regard to M34095, in the Ian Allan ABC British Railways Coaches 1958 & 1962 booklets, it is described as a prototype built for experimental use. So it may not have even been a fully completed vehicle or allocated a number. It may have been built for testing purposes only. If it didn’t have a service number, no one would have noted it. Once it’s experimental use was over in 1952, it may have then been sent to Wolverton to be completed as a service BSK. 1952 was the time of steel shortages and the building program was severely curtailed. There was probably pressure to make as much use as possible of what already existed and to keep the workshops and workers in employment. In the same way the demonstrator S15000 was converted to a service CK in 1952. Of course, this is all speculation. Hopefully more information will be uncovered that answers the gaps in what is known about the prototypes.

Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

×
×
  • Create New...