Why did the 20s outlast other classes?

[russ p]

I think 20s and 25s ride wise were much of a muchness 08s were the worst riding vehicle until MPVs were invented!

[25901]

Seconded with bells on!  Our Hymeks at Canton in the 70s were replaced by 25s, a very poor deal in my view.  The 00.25 Cardiff-Peterborough express parcels, which we worked to Gloucester and back with the same engine on the Peterborough-Cardiff balancing working, was an easily achieved 90mph delight with a Hymek, but a draughty, noisy, spine jarring, tiring nightmare with a 25 that struggled to reach the speed. and was diabolical once you got to 60 or above.  I wouldn't have called it bounce, as this implies that the springs didn't bottom out, which they bloody well did!  Few drivers were willing to push them to the limit; it felt and probably was dangerous...

 

 Don't forget the very strange shudder/wobble 25's had when shutting down

Edited December 26, 2017 by 25901

[andyman7]

Didn't the 25s develop body and cab rust issues later in life? 

I think they developed those pretty early in life....

[black and decker boy]

Don't forget the very strange shudder/wobble 25's had when shutting down

And starting up. I watched one at Springs Branch and was amazed the thing stayed on the track, such was the roll of the body just before it erupted into life

[Zomboid]

There was a very senior BR engineering manager called Freddie Harrison who had an unreasonable dislike of English Electric diesel products, and did his very best to prevent orders going to them.

He's certainly to blame for the vast numbers of class 47s with their too-highly-stressed Sulzer engines, instead of at least a proportion of DP2s. You can see the battles he lost when non-EE products failed to live up to expectations - additional Class 20 orders when the Claytons were such a disaster; the Class 50s, when the 47s had to be de-rated; and the re-engining of class 30 to class 31 with EE engines,

EE did types 1 and 3 very well, but their first type 4 (40s) were heavy and a bit under powered, and 50s weren't exactly known for their reliability. And the 31s were their second go at a type 2 after the baby Deltics weren't a huge success.

Not that I have anything against EE products, but they had their share of failures. BR wanting to have a choice of competent suppliers is totally understandable.

[25901]

EE did types 1 and 3 very well, but their first type 4 (40s) were heavy and a bit under powered, and 50s weren't exactly known for their reliability. And the 31s were their second go at a type 2 after the baby Deltics weren't a huge success.

Not that I have anything against EE products, but they had their share of failures. BR wanting to have a choice of competent suppliers is totally understandable.

 

To be honest the 31 was a case of fixing somebody else's problems (Mirrlees}

[newbryford]

EE did types 1 and 3 very well, but their first type 4 (40s) were heavy and a bit under powered, and 50s weren't exactly known for their reliability. And the 31s were their second go at a type 2 after the baby Deltics weren't a huge success.

Not that I have anything against EE products, but they had their share of failures. BR wanting to have a choice of competent suppliers is totally understandable.

 

As already mentioned, changing to EE power sorted out the 31.

The unreliability of the 50s wasn't entirely down to EE. EE wanted to build another 50 DP2s, but the BRB insisted on adding on other bits such as dynamic braking and slow speed control electronics.

 

Pretty certain that DP2 held a few records for reliability in service until it was unfortunately destroyed at Thirsk. It's engine later ended up in the 50s.

Cheers,

Mick

[The Johnster]

37s Achilles heel was a sensitive overload tripout; bit of a problem on some South Wales colliery work, and no doubt elsewhere as well.  Once saw one take over 2 hours for the half mile or so from the site of Abertillery station to Rose Heyworth colliery with 24ton empties in the 1980s; rail a bit greasy from overnight drizzle.  One could identify the moment the sand ran out!

[kevinlms]

A related question would be why so many other classes were commissioned once it was clear that a good, robust design had already been produced?

Something 'better' was looked for, primarily because the Class 20s had a disadvantage of being single ended. So the Clayton's came into being. As is well known, they were such a disaster, that when 'replacements' were required, the powers to be decided that perhaps, the Class 20s, weren't that bad after all!

[royaloak]

Seconded with bells on!  Our Hymeks at Canton in the 70s were replaced by 25s, a very poor deal in my view.  The 00.25 Cardiff-Peterborough express parcels, which we worked to Gloucester and back with the same engine on the Peterborough-Cardiff balancing working, was an easily achieved 90mph delight with a Hymek, but a draughty, noisy, spine jarring, tiring nightmare with a 25 that struggled to reach the speed. and was diabolical once you got to 60 or above.  I wouldn't have called it bounce, as this implies that the springs didn't bottom out, which they bloody well did!  Few drivers were willing to push them to the limit; it felt and probably was dangerous...

25s and suspension springs, dont make me laugh because they didnt have any, at least thats the impression you got at any sort of speed, all that banging and crashing!

[royaloak]

EE did types 1 and 3 very well, but their first type 4 (40s) were heavy and a bit under powered, and 50s weren't exactly known for their reliability. And the 31s were their second go at a type 2 after the baby Deltics weren't a huge success.

Not that I have anything against EE products, but they had their share of failures. BR wanting to have a choice of competent suppliers is totally understandable.

Since when were 31s an EE build?

[caradoc]

Maybe another small factor favouring the 20s was the Blue Star multiple working facility, allowing them to work with many of BR's other classes; For a while in the late 1980s some Ayrshire coal trains were worked by a 20 plus 37 combo, for example. 

[25901]

25s and suspension springs, dont make me laugh because they didnt have any, at least thats the impression you got at any sort of speed, all that banging and crashing!

 

A least one type 2 group will have good springs

[hmrspaul]

The 20s always seem a far more sensible loco to use on the Rail head treatment trains than 66s etc.

 

A couple of years ago I was walking (without a camera) over Holgate Road bridge and heard the most amazing sound - three 20s being given full welly as they accelerated under the bridge from the York freight avoiding lines with a train of loaded rail panels.

 

My earliest memory of 20s is on ECS at Euston, but it is great to be able to see them regularly nearly 60 years later.

 

Paul

http://paulbartlett.zenfolio.com/brclass20

[royaloak]

A least one type 2 group will have good springs

I do enjoy following your restorations, excellent work!

 

 

 

 

But I bet the 25 is still rough at speed! 

[royaloak]

Maybe another small factor favouring the 20s was the Blue Star multiple working facility, allowing them to work with many of BR's other classes; For a while in the late 1980s some Ayrshire coal trains were worked by a 20 plus 37 combo, for example. 

Would that be the same blue star as fitted to the 25s?

[caradoc]

Would that be the same blue star as fitted to the 25s?

 

Yes. And ?

[Titan]

Would that be the same blue star as fitted to the 25s?

 

 

Yes. And ?

 

The point made was that class 20's being blue star fitted was a small advantage over class 25. As both are in fact blue star fitted this is not so. I don't understand why that was so difficult for you to grasp that it necessitated that comment.

Edited December 28, 2017 by Titan

[cheesysmith]

I think he was inferring that the class 20 Vs the new standard type 1, the class 17s, which for a standard were fitted with a non standard MU system.

[coachmann]

When I was a member of the PRPC, one member justified his blurred photo of a Class 25 by saying the loco was ticking over so it must have been body roll!  Class 20 locos found a niche later in life hauling nuclear flasks economically seeing as two locos were specified for this traffic. Two Class 66's on one flask was overkill. The 20's always looked a bit bouncy to me when filming them at telephoto on Derby-Llandudno turns. I think I only ever saw one in days of green in the Manchester area............... It was in a convoy of other diesel locos that had stopped in Greenfield station and all looked pretty new or overhauled.

Edited December 28, 2017 by coachmann

[rodent279]

A related question would be why so many other classes were commissioned once it was clear that a good, robust design had already been produced?

The cynic in me suggests that the government of the day saw a means of diverting state funds into private industry!

 

I've said before elsehwere in this forum that I suspect, left to it's own devices, BR would have been happy with a fleet of 20's, 37's & 40's. That would have accounted for all but the heaviest freights & fastest passenger services.

 

There is also the issue of dual sourcing, i.e. not putting all your eggs in one basket. BR seemed to do this by purchasing complete locos off the shelf from different manufacturers, often with little in common between them. DB took this idea a step further, for example, the V200 diesel locos & Vt08/12 DMU's all used 3 different types of engine & 2 different types of transmission, all interchangeable. It was common for a loco to have two different engines & transmissions.

 

Not that they worked out of the box, they had their share of problems. I think the MAN engines were problematic in DB service as well as on BR, but not to the same extent as in the class 21/22's.

 

Getting back to class 20's, I wonder if the body design has a bearing on their longevity? Mention has been made of corrosion being less of an issue, is that perhaps because they are a very strong underframe with a lightweight fabricated body mounted on top, which is therefore perhaps easier to repair than the all-welded frame with sheet steel welded on top that was used on other types?

 

With the possible exception of the 08's they must have been BR's best buy.

Edited December 28, 2017 by rodent279

[rodent279]

As already mentioned, changing to EE power sorted out the 31.

The unreliability of the 50s wasn't entirely down to EE. EE wanted to build another 50 DP2s, but the BRB insisted on adding on other bits such as dynamic braking and slow speed control electronics.

 

Pretty certain that DP2 held a few records for reliability in service until it was unfortunately destroyed at Thirsk. It's engine later ended up in the 50s.

Cheers,

Mick

Slightly off topic-what happened to DP2's engine? Is it still around?

[royaloak]

I think he was inferring that the class 20 Vs the new standard type 1, the class 17s, which for a standard were fitted with a non standard MU system.

Ah I see, I thought he was referring to 20s.

 

Quite a few of the 17s were fitted with blue star, some from new and others were converted.

Edited December 29, 2017 by royaloak

[royaloak]

Slightly off topic-what happened to DP2's engine? Is it still around?

It ended its days in one of the 50s but was a bit broken so was stripped for spares and then scrapped.

[caradoc]

The point made was that class 20's being blue star fitted was a small advantage over class 25. As both are in fact blue star fitted this is not so. I don't understand why that was so difficult for you to grasp that it necessitated that comment.

 

Refer cheeyssmith's comment below; It was just a thought, that was all. Never mind, I will refrain from making any such comments in future.