Mark 3 Coach Bogie

[Davexoc]

July 83 Modern Railways mentions a possible BT10 development based on the workings of MagLev. So the primary suspension would be magnetic, but whether it came to fruition I don't know...

[david.hill64]

I think it is a BT15*. I remember riding in a test train with one of the coaches fitted with this bogie and seeing the look of disappointment on the face of the bogie engineer responsible for the project as the ride was, shall we say, disappointing. Mind you it was very difficult to match the ride of a BT10 when the dampers were in good shape. The vehicle was in the train as a make weight rather than being the primary focus of the tests.

 

* When I saw the photo BT 15 was my first guess, but there were other similar developments that tried to eliminate the panhard rod assembly of the BT10, so I may well be wrong.

[ISW]

1 hour ago, david.hill64 said:

* When I saw the photo BT 15 was my first guess, but there were other similar developments that tried to eliminate the panhard rod assembly of the BT10, so I may well be wrong.

 

I 'wish' you were right, as this is becoming a hard one to crack. However, as I said yesterday:

 

I found a reference to BT15 in The Railway Observer from 1979 "BT15: 11032 (Clouth primary suspension)." So that solves that one for you.

 

Clouth do 'rubber' suspensions, and my original photo shows coil springs.

 

Ian

[keefer]

Another one for the list is the BT5, used on the prototype (HST) Mk3 coaches (and the Mk1 RKB used in the set, although I've also read that it had BT10)

[ISW]

46 minutes ago, keefer said:

Another one for the list is the BT5, used on the prototype (HST) Mk3 coaches (and the Mk1 RKB used in the set, although I've also read that it had BT10)

 

Agreed. Here is an extract from the July 1975 issue of Modern Railway "Production Mk III coaches are equipped with the BT10 bogie, 
designed for high-speed running with minimum maintenance.  Changes from the prototype BT5 version (described and illustrated 
in the June 1972 issue of Modem Railways) are minimal."

 

Plus:

BT8 - Used on Class 312/0, 312/1 & 312/2 BDTSOL, TSO & DTCOL coaches (Modern Locomotives Illustrated Dec-2017 / Jan-2018 & Nov-2018 / Dec-2018 issues).

 

Ian

[ISW]

Some more for the 'list' started by @25kV:

 

BT38 / BT38b - Used on Class 153 & 155s (Modern Locomotives Illustrated Feb-2015 / Mar-2015).

BT52 - Class 323 & Class 465 (Alsthom built) (Modern Locomotives Illustrated Feb-2017 / Mar-2017 & Dec-2017 / Jan-2018).

T3-7 - Class 319 & 321 (Modern Locomotives Illustrated Dec-2017 / Jan-2018).

T3-17 - Used on Class 165 Networker Turbos & Class 166 Networker Expresses (Modern Locomotives Illustrated Dec-2015 / Jan-2016).

T3-23 - Used on Class 168 Clubmans (Modern Locomotives Illustrated Dec-2015 / Jan-2016).

T3-23c - Used on Class 170 Turbostars  (Modern Locomotives Illustrated Dec-2015 / Jan-2016).

 

Ian

[Wickham Green too]

3 hours ago, keefer said:

Another one for the list is the BT5, used on the prototype (HST) Mk3 coaches ...

... again, not what we're looking for : Shildon, 31/8/75 

 

Edited November 6, 2023 by Wickham Green too

[Peter Kazmierczak]

Yep, the BT5 was on the prototype HST. One bogie was displayed outside Derby's Industrial Museum - dunno if it's still there.

[Wickham Green too]

Probably floated away last week ......

[Peter Kazmierczak]

Has anyone mentioned the nomenclature of bogies?

B = 2-axle
T = trailer (unpowered)

So 3-axle bogies were C and powered axles were P

[keefer]

35 minutes ago, Peter Kazmierczak said:

Has anyone mentioned the nomenclature of bogies?

B = 2-axle
T = trailer (unpowered)

So 3-axle bogies were C and powered axles were P

I knew about the T/P difference but hadn't occurred to me the about the B/C. Fits in with the prototype CP1 bogies on 56042 which led to the CP3 on the cl.58.

[david.hill64]

IIRC the BT5 was a heavyweight version of the BT10, also used on the 'special vehicles' (Royal Train) project.

[RetiredBod]

Another one for the list?  I was involved with the testing of the ABB prototype T4-5 variant that went into production fitted under the EPS Nightstock Coaches. The testing was done on the ECML in July/Aug 1993 with a pair of bogies fitted under MkIV 10310.  The bogies were proved up to 125mile/h + stability for 10% overspeed (137.5mile/h).  

 

Edited November 7, 2023 by RetiredBod

[ISW]

So, getting desperate, I cropped my original photo down to just the mystery bogie and used that in a Google reverse photo search. There are quite a lot of bogie photos in t'internet, but none (!) were exactly like the mystery one.

 

The closest I found were the bogies fitted to Mk3 sleeper 10612 (in October 2015). Here are photos of those bogies:

 

The designations BT10A & BT10B are in the Article (link below) are are nothing I added.

http://www.cornwallrailwaysociety.org.uk/latest-input--news--old-pictures-etc/cornwall-expo-2015-a-special-report-part-2-by-mick-house

 

They have the 'look' of my mystery bogie, but with rubber primary (Clouth??) instead of coil springs.

 

Does this 'jog' anyone's memories? Is it just the same as a BT15 (which also a BT10 with a rubber primary suspension - see my posting of 05/11/23 @20:13) and/or is it the same as the BT10b 'upgrade' (also referenced in my posting of 05/11/23 @20:13)?

 

Does that make my mystery bogie a BT10C??

 

Ian

[ISW]

It's a bit of a long-shot, but @mjkerr mentions the Mk10A & Mk10B bogies in a 2011 posting on RMWeb: 

 

 

Maybe he could help out ...

 

Ian

[ISW]

24 minutes ago, ISW said:

Does that make my mystery bogie a BT10C??

Nah, got that idea wrong. Found this in a 2010 posting on railforums.co.uk:

 

There are four sub-type of the BT10 bogie:
BT10 - 125mph
BT10A - 110mph
BT10B - 125mph
BT10C - 100mph

The BT10C was designed specifically for the sleepers. Close up you will notice that it has additional levelling valves (these are easier to see when standing facing the bodyside, looking at the right hand bogie). There is also a different Swing Link configuration. Finally, it is also heavier, by about 350kg.

 

Still don't know what the mystery bogie is ...

 

Ian

[seraphim]

Others beat me too it, but I'm fairly sure the photo is the BT15 bogies. Ended up under scrap sleeper cars if memory serves.

 

There are many, many different sub-types of BT10 bogie, but the main ones are as follows:-

- BT10A - early type with bolted joints securing the lateral control rod brackets to the bogie frames. This area was found to be prone to cracking, which led to...

- BT10B - where the LCR brackets were formed of a casting which was welded into the bogie frame. BT10A was not permitted for use on HST.

 

I have never heard of a BT10C (and I wrote the bogie overhaul manual....). Sleepers were late build, and consequently were built with BT10B bogies. In theory, BT10As could have been fitted (being LHCS, not HST, vehicles. But the reality was that the overhaul processes for Sleepers kept their bogies in a self-contained pool.

 

There were allegedly some "special" BT10s with beefed-up platework used on the Royal saloons based on MkIII bogies. But I never dealt with those (and never saw one).

 

Other main variations:-

- Long and short swing link bogies. LSL bogies were the original design, and rode better (it's a principle that the longer the swing link, the better the ride). But they also had a minor gauge infringement which was an issue on 3rd rail lines. So, XC HSTs, which went to Bomo, had to be 100% BT10B SSl.

- Wheelslip types - at least four types - Girling self-powered, Girling Coach powered (both rubbish), BR MK2 (less rubbish) and Westinghouse (pretty good).

 

Add into the mix that different types of coach had different spring arrangements. Yellow and Green springs - and the famous GNER yellow springs which were painted red because it looked nice.

 

Keeping on top of this lot made for a busy existence.

[seraphim]

And how could I forget my least favourite coach of them all - 12140? Never fitted with BT10 bogies, it had at least two different designs in its life, ending up on BT46 bogies similar to MkIII DVTs. But only similar - not identical - and hence becoming a nightmare at each and every bogie overhaul. I was promised a trip to the breakers on the day it was cut. Bit like going to a funeral "just to make sure".

[tiger]

On 05/11/2023 at 03:08, ISW said:

I have this photo I took in 1981 at Doncaster of a pair of Mark 3s on an HST showing the bogies. The one on the right is a 'normal' BT10 bogie, but what's that one on the left?

 

Ian

 

I've been following this thread with interest for a few days. I think the mystery bogies on E42224 are BT17 but only have "keyboard warrior" level evidence...bear with me.

 

As confirmed by others the bogies on Mk3 sleeper 10612 are BT15 with two Clouth rubber springs per axle box, and one suspension damper. There are a few pictures online of the same bogie type under Mk3a TSO M12010 in blue/grey livery: M12010 on Facebook.

 

There are a couple of threads on Robert Carroll's "BR Coaching Stock" groups.io (formerly yahoo) site which mention Mk3 coaches with alternative bogie types. One post in particular mentions the following: (link to post by David Hatt)

 

"The primary springs on BT15 bogies were Clouth rubber units. Unfortunately these springs experienced excessive rates of creep (settlement) and were deemed unsatisfactory. This led to the development of the BT17 bogie, where the Clouth units were replaced by coil springs with rolling rubber ring units inside them."

The same poster responded to my request for more information about Mk3 coach bogies with the following comment (link)

 

"BT17 bogies had two coil springs per axlebox, each spring surrounding a rolling rubber ring unit. This arrangement replaced the pair of Clouth springs on each axlebox of the BT15 bogies."

So I reckon your mystery bogies on E42224 match this description perfectly and look very similar to the BT15 bogies identified in other photos.

 

Both of these threads on BR Coaching stock have interesting details about MK3 coaches fitted with unusual bogies including the infamous coach, M12140. There's a great picture of this coach in Virgin livery with T4 bogies on Facebook courtesy of Steve Jones.

 

By chance I got to ride in 12010 and 12140 once each, both back in 1990. 12010 was sent up to Craigentinny for the last few weeks of class 47/7 push/pull workings on the Edinburgh-Glasgow route, while the original Mk3 coach fleet was sent back to Intercity via refurbishment. I rode in it from Glasgow to Edinburgh in March 1990 - it had the red refurbished Intercity 76 seat interior by then. I think its the first vehicle in this rake (Flickr photo) - you can just about make out the different bogie profile.

 

12140 was in a rake I rode in from Liverpool to Euston the same year. It too had been refurbished internally and by then had T4 bogies. It's a long time since both trips but I reckon the ride was better in 12140 than 12010, but 12010 was pretty good.

Hope this is correct information (!) and of interest, and I hope the various parties who I have quoted or linked photos to don't mind. You might need to get a groups.io account or join the relevant Facebook group to see some of the threads/photos - not ideal, but that's where I found the info.

 

Cheers

 

Tom R (aka tiger)

Edited November 9, 2023 by tiger

[ISW]

5 hours ago, tiger said:

I've been following this thread with interest for a few days.

Very glad to hear someone else was interested ...

 

5 hours ago, tiger said:

I think the mystery bogies on E42224 are BT17 but only have "keyboard warrior" level evidence...bear with me.

Brilliant. Well done that man.

 

Your 'evidence' does seem to be well founded and shows, for one thing, that I should become a member of Robert Carroll's "BR Coaching Stock" groups.io!.

 

Here is a 'possible' timeline:

• BT15 bogies were installed on Mk3 loco haul stock in ~1979 (The Railway Observer)
• My photo of the mystery bogie dates from 1981
• The Facebook link you sent states regarding Mk3 TSO M12010 "Another experiment that arrived at Longsight in 83 was this Mk3 TSO which had been given modified bogies. I don't know if they had been reclassified but were essentially BT10s altered to use Clouth springs."
• In https://www.diva-portal.org/smash/get/diva2:675174/FULLTEXT01.pdf it says
  "In evaluation of the HST tests, it was possible to compare results from coaches with different bogies. The coach with BT17 bogies had a poorer ride than the coach with B10 bogies, and the r.m.s. values for vibrations were approximately 10% higher. Despite this fact, there were no significant differences in the comfort ratings of the test subjects (Harborough1984, Harborough1986a)."
  and
  "During1983-1984, comfort tests were conducted with an HST (High Speed Train) and an APT (Advanced Passenger Train). In the HST tests, MkIII coaches were used, one with BT10 bogies and one with BT17 bogies. The coach with BT17 bogies had  defective dampers and therefore had worse dynamic behaviour than expected (Chapell 1984)."

What is not clear is 'when' was the BT17 developed out of the BT15? My photo shows it to be 1981 or earlier, but the other extracts above could be construed as to imply a later date?

 

Based on the above, we have to conclude that the statement in http://www.traintesting.com/M12140_Mk3_coach.htm that "BT17 bogie was a BT10 but with coil/rubber pedestal primaries and was fitted under Mk3 coach No: M12093." is incorrect, and should say BT15.

 

Now you have 'pointed us in the right direction', some searching for BT17 bogies can commence ...

 

Ian

 

[keefer]

32 minutes ago, ISW said:

"BT17 bogie was a BT10 but with coil/rubber pedestal primaries and was fitted under Mk3 coach No: M12093." is incorrect, and should say BT15.

But BT17 is correct according to the posts above?

i.e. BT15 had rubber units only but BT17 had coil springs with rubber units inside the coils.

7 hours ago, tiger said:

"BT17 bogies had two coil springs per axlebox, each spring surrounding a rolling rubber ring unit. This arrangement replaced the pair of Clouth springs on each axlebox of the BT15 bogies."

Apologies if I'm misunderstanding what you mean.

[ISW]

20 hours ago, keefer said:

But BT17 is correct according to the posts above?

i.e. BT15 had rubber units only but BT17 had coil springs with rubber units inside the coils.

You make a good point there.

 

But ... I've seen no evidence that M12093 was fitted / retrofitted with BT17 bogies. The Railway Observer (September 1979) does state that M12093 was fitted with BT15s though.

 

I can't the only person with a photo of this BT17 bogie (assuming that E42224 was indeed so fitted) ... It must have made it onto some other Mark 3 coaches?

 

Ian

[keefer]

@ISW ah, you meant the coach number. I missed the RO reference about BT15.

Apologies.

 

 

Edited November 10, 2023 by keefer

[keefer]

Platform 5 books, i forgot to check mine.

1979: M12140 - BT7, M12093 - BT15

1986: 12056 - BT7, 11032/12062/12093 BT15

1988: As 1986 but 11032 is missing (converted to RFM 10215)

 

Sorry if I've missed it previousy but have seen mention of BT7 being the loco-hauled stock equivalent of the BX1 EMU bogie (cl.313-315)

[ISW]

4 hours ago, keefer said:

@ISW ah, you meant the coach number. I missed the RO reference about BT15.

Apologies.

 

 

No need to apologise. I think I was clutching at straws ... 'Maybe' M12093 had its BT15s retrofitted with coils to become BT17? Any evidence gratefully received!

 

Ian