Kernow Models D6xx Update

[Gwiwer]

They were something of a prototype hence only five built. They worked the best express passenger trains between Plymouth and Paddington replacing steam and they worked some express parcels and milk trains to the capital as well. They have also been noted on Old Oak Common empty stock duties.

 

They were considered unreliable, probably fair comment given the overall performance of North British diesel types, and were banished to Cornwall. That had the advantages of concentrating a small class in a small area reducing the number of types an Exeter or London driver (for example) had to sign and allowing just a single set of spares to be held at Laira depot. They were also "hidden" from senior management and a breakdown was less obvious than if the Cornish Riviera sat down on the main line at Savernake.

 

They were "maids of all work" west of the Tamar with duties including the heavy sleeping car trains where they usually came on at Plymouth relieving a Western then worked back up from Penzance later in the day which might be on vans. They had regular, even specific, duties some of which are recorded in the "Book of the Warships". They still ran up as far as Exeter but seldom on Class 1 work.

 

With typically three of five to cover three rosters you didn't often see more than one at a time except at Plymouth though two together at Penzance wasn't unheard of and I once found three there.

 

They were used alongside the D8xx Warships rather than Hymeks since the latter were considered mixed-traffic locos whereas Warships were express passenger types. Being non-standard and a small unreliable class they were withdrawn relatively early and their duties in Cornwall taken over by Westerns which until then had been less common west of Plymouth.

[adb968008]

So if I get right, between 63- withdrawal, they were pretty much Cornwall (Exeter-Penzance area), on express, sleepers ? - freight ?, presumably keeping them local keeps them reliable, and frees up other Warships for further afield.

 

I was initially thinking they would be good hill climbers over a Warship given the extra weight, but see it’s an A1A-A1A not a Co-Co so just fat and heavier than a 42 it’d presumably be worse with Some HP going to drag that extra weight, 117 vs 79 tons... it’s a whole mk1 heavier than a Warship, nearly 10 tons over a Western.

 

Did these need the 2 hours preheating like Maybachs .

 

Fascinating class, they were only a year earlier than the 42’s, so much of this must have been known already.

 

were they really Warship prototypes or was this a popular story..?, there’s not much in common with a 42 and not much more with a 43 ? And why 5, not 1 or 2 like all other prototypes ?, was it possible these were meant to rival or be an alternate to a Warship, which someone convinced a run of five, but may have considered to be more ?

 

D600 delivered Jan 1958

D800 delivered Aug 1958

Forget the drawing board, or the jigs and tools, D800 must be already in assembly in January 1958... so if D600 was an eval, it was already too late for D800 ? Or was it a prototype for NBLs class 43’s ?

 

D833 delivered Aug 1960 ? - but isn’t this just a 42 with MAN/Voith rather than Maybach.

 

 

Don’t suppose there’s a source for further reading on these ?

 

Of all the prototype diesels so far, these seem to be a rebel without a cause ?

 

Unlike the 53, it’s a Diesel electric vs a Hydraulic version of a Western, and DP2 as a competitor but these things... ?

Edited October 8, 2017 by adb968008

[Kelly]

They were ordered as part of the original Pilot Scheme. Numerous texts on the mistakes made as a result of and during that time. Some designs being ordered almost entirely before the pilot scheme locos had been delivered or built.

 

There is a book called Hydraulic Vs Electric which looks at the cases in detail.

[Dunsignalling]

So if I get right, between 63- withdrawal, they were pretty much Cornwall (Exeter-Penzance area), on express, sleepers ? - freight ?, presumably keeping them local keeps them reliable, and frees up other Warships for further afield.

 

I was initially thinking they would be good hill climbers over a Warship given the extra weight, but see it’s an A1A-A1A not a Co-Co so just fat and heavier than a 42 it’d presumably be worse with Some HP going to drag that extra weight, 117 vs 79 tons... it’s a whole mk1 heavier than a Warship, nearly 10 tons over a Western.

 

Did these need the 2 hours preheating like Maybachs .

 

Fascinating class, they were only a year earlier than the 42’s, so much of this must have been known already.

 

were they really Warship prototypes or was this a popular story..?, there’s not much in common with a 42 and not much more with a 43 ? And why 5, not 1 or 2 like all other prototypes ?, was it possible these were meant to rival or be an alternate to a Warship, which someone convinced a run of five, but may have considered to be more ?

 

D600 delivered Jan 1958

D800 delivered Aug 1958

Forget the drawing board, or the jigs and tools, D800 must be already in assembly in January 1958... so if D600 was an eval, it was already too late for D800 ? Or was it a prototype for NBLs class 43’s ?

 

D833 delivered Aug 1960 ? - but isn’t this just a 42 with MAN/Voith rather than Maybach.

 

 

Don’t suppose there’s a source for further reading on these ?

 

Of all the prototype diesels so far, these seem to be a rebel without a cause ?

 

Unlike the 53, it’s a Diesel electric vs a Hydraulic version of a Western, and DP2 as a competitor but these things... ?

The question that needs answering is not when D600 was delivered, but when construction of it began..............

 

It can be argued that many lessons had been learned from it before it even turned a wheel. The prime one being how not to build a diesel-hydraulic locomotive!

 

The D800s reflected what had been going on in Germany rather than what had been going on in Scotland.

 

John

Edited October 8, 2017 by Dunsignalling

[Ian Hargrave]

What were the D600’s used along side for, and at what point did their role start to fade ? (I’m thinking 1963-67, after most Hymeks, Warships and Westerns were delivered).

 

We’re they rostered alongside Warships or Hymeks, I can’t imagine putting them on a Western duty resulted in much fun ?, even a Warship duty looks a little challenged ? Or were they used on steam replacement diagrams ?

As a class of 5 I can’t imagine they were replaced by anything, i’d Assume they were redundant from an early stage ?

 

The Westerns...like their Swindon built Warship sisters had previously been...were slow on delivery into traffic and were not sufficient in quantity until the autumn of 1962 when they took over the King duties on the Paddington-West Midlands-Birkenhead route. By this time,the NBL D 6XX had been relegated to secondary turns and those,as Gwiwer has posted,mainly west of Exeter.My own last sighting of one on a West of England-Paddington service ( and that a rarity in itself ) was dated August 11th 1961 at Wellington ( Somerset ).

 

There was no common working on express passenger turns .There were eventually 71 D 8XX in service and they held sway throughout the BR Bristol and West areas. I regular observation at Temple Meads between 1960 and 1962, saw no D 6XX. If they did experience such a thing as a heyday,it faded by the very early 1960's.

 

Powering up the West of England services later in the 1960's pairs of D 8XX Warships were used for a time in an attempt to improve schedules.

[adb968008]

Thanks this is interesting.

 

I’ve got two of these ordered, I kind of suspect the model, if all wheel drive, is probably going to be better than the prototype and out pull a Bachmann warship :-) wouldn’t that be a modelling first.. a model that’s too good.

[SRman]

Thanks this is interesting.

 

I’ve got two of these ordered, I kind of suspect the model, if all wheel drive, is probably going to be better than the prototype and out pull a Bachmann warship :-) wouldn’t that be a modelling first.. a model that’s too good.

 

Already been done! Heljan's class 128 DPU pulled something like 36 coaches on Gwiwer's old layout, including some gradients  ... just a few more coaches than the real ones could manage!!

[The Stationmaster]

So if I get right, between 63- withdrawal, they were pretty much Cornwall (Exeter-Penzance area), on express, sleepers ? - freight ?, presumably keeping them local keeps them reliable, and frees up other Warships for further afield.

 

I was initially thinking they would be good hill climbers over a Warship given the extra weight, but see it’s an A1A-A1A not a Co-Co so just fat and heavier than a 42 it’d presumably be worse with Some HP going to drag that extra weight, 117 vs 79 tons... it’s a whole mk1 heavier than a Warship, nearly 10 tons over a Western.

 

Did these need the 2 hours preheating like Maybachs .

 

Fascinating class, they were only a year earlier than the 42’s, so much of this must have been known already.

 

were they really Warship prototypes or was this a popular story..?, there’s not much in common with a 42 and not much more with a 43 ? And why 5, not 1 or 2 like all other prototypes ?, was it possible these were meant to rival or be an alternate to a Warship, which someone convinced a run of five, but may have considered to be more ?

 

D600 delivered Jan 1958

D800 delivered Aug 1958

Forget the drawing board, or the jigs and tools, D800 must be already in assembly in January 1958... so if D600 was an eval, it was already too late for D800 ? Or was it a prototype for NBLs class 43’s ?

 

D833 delivered Aug 1960 ? - but isn’t this just a 42 with MAN/Voith rather than Maybach.

 

 

Don’t suppose there’s a source for further reading on these ?

 

Of all the prototype diesels so far, these seem to be a rebel without a cause ?

 

Unlike the 53, it’s a Diesel electric vs a Hydraulic version of a Western, and DP2 as a competitor but these things... ?

 

As ever 'The Book Of The Warships' is the reference to consult -

 

January 1955 NBL were given an intimation than the BTC would place an order with them to design and construct a 2,000hp  diseel-hydraulic loco for the Western Region

NBL delivered their specification on 22 February 1955

The BTC placed the order on 16 November 1955

NBL's work programme dated 13 February 1956 stated -

March 1956 Main shape finalised

July 1956 Details finished

February 1957 First loco delivered

There was then various to-ings & fro-ings between the BTC and BNBL over design details including teh shape of the loco

 

On 25 November 1957 the BTC announced that the first loco had been completed.

D600 arrived at Swindon on 14 February 1958 and was released from works for crew training on 24 January, it worked a press demonstration trip on 17 February.

 

D800 was officially 'unveiled' at Swindon on 14 July 1958 having been out on trials during the previous month

 

Swindon had begun to receive V200 drawings from Krauss Maffei in the Spring of 1956 at which point design work got underway on D800, again there were numerous debates over detail design and appearance and of course the works had to find its feet with a completely new method of construction - effectively D800 was hand built and used to create the jigs to build its successors.

 

So in reality the design of the two classes proceeded more or less in parallel with the Western going very much for what was seen as the advantages of the German approach to the advantages of using the diesel hydraulic layout (high power to weight ratio) which accordingly involved new construction techniques while North British (with occasional exceptions such as the cast aluminium nose for the D600) worked very much along traditional lines.  The first main production batch of 30 D800s was ordered in 1957 - before D 600 had even reached the Western Region let alone been put to work.  And - as can be seen D600 was not a year ahead of D800 as it had been out on trial running in 1957 and D800 was out on trial running in June 1958.

 

In simple terms I think it's fair to summarise that the NBL design was not at all like the Western's idea of what a diesel-hydraulic loco should be like - it was heavy and it was carting round useless carrying wheels in a 3 axle bogie whereas Swindon's design was putting down similar horsepower through two axle bogies.

[Metr0Land]

I always understood D800-D802 were all hand built, hence the out of sequence names, whereas D803 onwards were in alphabetical order (until they renamed D812!)

 

Happy to be corrected if that's not the case.

[Gwiwer]

812 was never to my understanding re-named visibly. Although the intended "Despatch" plates were cast (and I believe still exist) the loco was released to traffic carrying "RNR" from new. Whether or not its intended plates were ever physically attached perhaps a historian or class expert might know.

[Roy Langridge]

812 was never to my understanding re-named visibly. Although the intended "Despatch" plates were cast (and I believe still exist) the loco was released to traffic carrying "RNR" from new. Whether or not its intended plates were ever physically attached perhaps a historian or class expert might know.

That is my understanding too. I thought one of the Warship books had an ex-works photo with RNR, kind of proving it never carried Despatch. I will have a hunt later.

 

Roy

[Ian Hargrave]

812 was never to my understanding re-named visibly. Although the intended "Despatch" plates were cast (and I believe still exist) the loco was released to traffic carrying "RNR" from new. Whether or not its intended plates were ever physically attached perhaps a historian or class expert might know.

 

That is my understanding too. I thought one of the Warship books had an ex-works photo with RNR, kind of proving it never carried Despatch. I will have a hunt later.

 

Roy

 

Correct,gents..RNR it was.

[The Stationmaster]

812 was never to my understanding re-named visibly. Although the intended "Despatch" plates were cast (and I believe still exist) the loco was released to traffic carrying "RNR" from new. Whether or not its intended plates were ever physically attached perhaps a historian or class expert might know.

 

I saw it within a few days of it entering traffic and RNR it was.

[BR(S)]

The Kernow EP was running successfully on a layout at Peterborough yesterday. Had a full load of coaches on when I saw it.

[rembrow]

The Kernow EP was running successfully on a layout at Peterborough yesterday. Had a full load of coaches on when I saw it.

Was it running at a realistic speed for an express diesel type, as there has been concern about the speed range, due to the DJ Models Class 71 having a low top speed, when pulling a coach load, due to the coreless motor used or the gearing system. DJ Models are building the D600 using a similar motor/drive system as the Class 73

Edited October 15, 2017 by rembrow

[Kelly]

Was it running at a realistic speed for an express diesel type, as there has been concern about the speed range, due to the DJ Models Class 73 having a low top speed, when pulling a coach load, due to the coreless motor used or the gearing system. DJ Models are building the D600 using a similar motor/drive system as the Class 73

I think you meant the class 71, the 73 was Dapol.

[rembrow]

 

I think you meant the class 71, the 73 was Dapol.[/quote

 

Woops, sorry about that. Yes Class 71, I should know as I've got two of them.Have edited my previous post

Edited October 15, 2017 by rembrow

[Ian Hargrave]

Was it running at a realistic speed for an express diesel type, as there has been concern about the speed range, due to the DJ Models Class 71 having a low top speed, when pulling a coach load, due to the coreless motor used or the gearing system. DJ Models are building the D600 using a similar motor/drive system as the Class 73

As one who raised the issue,I am confident that all will be well in that quarter.I now await the day when Ark Royal glides majestically at the head of 8 or 9 chocolate and cream Bachmann MK 1's at reasonable prototype speed.

[Gwiwer]

the DJ Models Class 71 having a low top speed, when pulling a coach load, due to the coreless motor used or the gearing system. 

 

Neither.  Try power-routing.  In any case I think we can say lesson learned and that the 6xx will run at suitable speeds.

[rembrow]

 

Neither. Try power-routing. In any case I think we can say lesson learned and that the 6xx will run at suitable speeds.[/quote

 

What is power routing. As I run the layout on dc, am unable to adjust the speed settings via dcc chip. Would rather have confirmation of the speed output having had disappointment with the 71 mechanism and two (out of two) J94s that were inoperative on delivery, so for me I'm now sceptical about DJ models drive systems. Lovely models for body moulding and livery though.

[Gwiwer]

What is power routing.

 

The inner circuitry of the locomotive.  Power is taken from the rails whether DC or DCC and feeds the motor but also feeds ancillaries such as lighting.  Depending on exactly how much current is diverted and how to the lighting it is possible that performance can be affected.  I found a way to improve class 71 speed on DC (only) by clipping a connection on the PCB.  Do that on DCC however and the locomotive might never run again.

Edited October 15, 2017 by Gwiwer

[Clive Mortimore]

The big Warship looked good running at the Peterborough show today, thanks to the guys on Hinton Parva for letting me have a close view of it and the Bulleid 1co-Co1. Both look very good and were hauling fair sized trains. I am still trying to find a reason for having a third one on an Eastern Region layout.

Edited October 15, 2017 by Clive Mortimore

[Graham_Muz]

Was it running at a realistic speed for an express diesel type, as there has been concern about the speed range, due to the DJ Models Class 71 having a low top speed, when pulling a coach load, due to the coreless motor used or the gearing system. DJ Models are building the D600 using a similar motor/drive system as the Class 73

 

It was running on the High Wycombe and District MRS layout Hinton Parva all 32ft x 10ft of it and hauling a full rake as part of our sequence. She effortlessly and a full range of speeds, with plenty of power in reserve I can assure you. I thank the guys at Kernow for letting us have a play and give the EP a good running in session for all 15 hours of the show (as we started running our sequence 30 mins before opening each day) 

 

As many will know I am not a Western man (we had the Bulleid diesel running too which kept me happy) but by all accounts she, like the Bulleid,  ran well with no issues over power, haulage capability or running qualities.

 

The big Warship looked good running at the Peterborough show today, thanks to the guys on Hinton Parva for letting me have a close view of it and the Bulleid 1co-Co1. Both look very good and were hauling fair sized trains. I am still trying to find a reason for having a third one on an Eastern Region layout.

 

Clive, It was a pleasure to let you have a closer look at the D600 and the Bulleid Diesel, I did wonder, as you were describing your building exploits, if it was you I was speaking to!

 

Anyway a few pictures as requested...

 

[Clive Mortimore]

It was running on the High Wycombe and District MRS layout Hinton Parva all 32ft x 10ft of it and hauling a full rake as part of our sequence. She effortlessly and a full range of speeds, with plenty of power in reserve I can assure you. I thank the guys at Kernow for letting us have a play and give the EP a good running in session for all 15 hours of the show (as we started running our sequence 30 mins before opening each day) 

 

As many will know I am not a Western man (we had the Bulleid diesel running too which kept me happy) but by all accounts she, like the Bulleid,  ran well with no issues over power, haulage capability or running qualities.

 

 

Clive, It was a pleasure to let you have a closer look at the D600 and the Bulleid Diesel, I did wonder, as you were describing your building exploits, if it was you I was speaking to!

 

Anyway a few pictures as requested...

 

D600_1.jpg

D600_2.jpg

D600_3.jpg

Thank you Graham. I liked the gas turbine models that were running today.

[PrestburyJack]

I found a way to improve class 71 speed on DC (only) by clipping a connection on the PCB.  Do that on DCC however and the locomotive might never run again.

 

Hi, which connection is that please, do you have a photo?

 

Thank you.