72xx question

[Clearwater]

Seeing Castle's evocative photo of a partially reassembled 7202 outside Didcot made me wonder what it would be like to ride behind as a passenger loco. I've read that the 42xx had a pronounced push/pull effect giving a jerky ride, and that was my impression on my trip to the Gloucestershre and Warwickshire, hence they were not commonly used in passenger traffic. I assume the 72xx had similar characteristics?

 

I know the 42s were trialled as bankers. Were the 72s similarly employed? I don't think I've ever seen any pictures of either class on passenger trains in regular service days

 

David

[Castle]

Hi David,

 

Have a look at a copy of the excellent book Great Western Eight Coupled Heavy Freight Locomotive's by David Maidment. Well worth the money! There is a picture on page 72 (coincidence?!) of No. 7225 on the 13:15hrs Canton to Birmingham Snow Hill in about 1960. The caption says that, on a summer Saturday, when the amount of available motive power at Canton was getting thin on the ground, that 8Fs and 28XXs were common passenger train performers but occasional bottom of barrel scraping manoeuvres would result in things such as 72XXs appearing. Whilst not common, it probably wasn't unheard of for these great old beasts to perform on passenger trains. As to what it was like on the footplate of a powerful monster like that at any speed above their normal Freight train repatoire, I think that with two massive pistons pounding fore and aft and 33,170lbs tractive effort, it would be exciting in all the wrong ways...

 

The 72XXs were used as bankers at Abergavenny for many years with great success. They were also trialled on the Licky but according to Maidment, clearance issues were experienced with the platforms at Bromsgrove.

 

I hope this helps!

 

All the best,

 

Castle

Edited January 6, 2017 by Castle

[Devo63]

In issue 18 (Spring 1996) of Great Western Railway Journal there is an article on the 72XX. There are no photos of them hauling passenger stock but a reference is made that during the war they could be "seen from time to time with passenger vehicles, especially empty stock." The same article stated that they were used on banking duties in 1937/38 at Aberbeeg and 7231 was tried out at Brimscombe in 1940/41.

 

Dave R. 

[Clearwater]

Thanks- I'll take a look at the eight couples book. Presume GWS will hire the loco out? I guess it will get some good power outputs on some of the larger, graded preserved lines?

 

David

[steam69]

Seeing Castle's evocative photo of a partially reassembled 7202 outside Didcot made me wonder what it would be like to ride behind as a passenger loco. I've read that the 42xx had a pronounced push/pull effect giving a jerky ride, and that was my impression on my trip to the Gloucestershre and Warwickshire, hence they were not commonly used in passenger traffic. I assume the 72xx had similar characteristics?

 

I know the 42s were trialled as bankers. Were the 72s similarly employed? I don't think I've ever seen any pictures of either class on passenger trains in regular service days

 

David

There is good photograph of a 42xx leaving Bristol Temple Meads by Ben Brookbanks excellent site - https://commons.wikimedia.org/wiki/File%3ABristol_Temple_Meads_geograph-2542324-by-Ben-Brooksbank.jpg

 

Richard

[Poor Old Bruce]

A lot of GW engines transmitted a fore-and-aft movement into the train. I have also experienced it with some Standard types and B1s. AFAIK it is down to the amount of balancing for rotating and reciprocating masses and their effects on hammerblow.

[The Stationmaster]

Hi David,

 

Have a look at a copy of the excellent book Great Western Eight Coupled Heavy Freight Locomotive's by David Maidment. Well worth the money! There is a picture on page 72 (coincidence?!) of No. 7225 on the 13:15hrs Canton to Birmingham Snow Hill in about 1960. The caption says that, on a summer Saturday, when the amount of available motive power at Canton was getting thin on the ground, that 8Fs and 28XXs were common passenger train performers but occasional bottom of barrel scraping manoeuvres would result in things such as 72XXs appearing. Whilst not common, it probably wasn't unheard of for these great old beasts to perform on passenger trains. As to what it was like on the footplate of a powerful monster like that at any speed above their normal Freight train repatoire, I think that with two massive pistons pounding fore and aft and 33,170lbs tractive effort, it would be exciting in all the wrong ways...

 

The 72XXs were used as bankers at Abergavenny for many years with great success. They were also trialled on the Licky but according to Maidment, clearance issues were experienced with the platforms at Bromsgrove.

 

I hope this helps!

 

All the best,

 

Castle

 

A lot of Welsh enginemen were far from keen on 72XX on longer distance freight & mineral workings so the language on one on a passenger turn was probably more than hot enough to keep steam pressure really high.  Allegedly very hot and uncomfortable cabs prone to dust as well.

[Horsetan]

A lot of GW engines transmitted a fore-and-aft movement into the train. I have also experienced it with some Standard types and B1s. AFAIK it is down to the amount of balancing for rotating and reciprocating masses and their effects on hammerblow.

 

More prevalent on two-cylinder (outside) types?

[Silver Sidelines]

Would the 72xx etc have steam heating?  The majority of goods engines were not steam heat equipped and have had to be retrofitted for preservation use.

 

Ray

[PhilH]

Although not a 72xx (obviously...) we had 4270 on the Mid Hants for a while. it could pull a house down but was by a huge margin the most uncomfortable engine I have ever driven. It felt like it was shaking itself to pieces at anything over 10mph, cramped cab with every control seemingly in an awkward place.

 

The GWR certainly didn't pander to the creature comforts of its footplate crews.

[The Stationmaster]

Would the 72xx etc have steam heating?  The majority of goods engines were not steam heat equipped and have had to be retrofitted for preservation use.

 

Ray

 

Mamby pamby stuff - you didn't need steam heat on a train outside the heating period so it didn't matter.  And in any case the steam pipes would have been taken off the stock so there was no way for the steam to get to them.

Edited January 6, 2017 by The Stationmaster

[Castle]

Hi All,

 

Thanks- I'll take a look at the eight couples book. Presume GWS will hire the loco out? I guess it will get some good power outputs on some of the larger, graded preserved lines?

David

It would be silly not to let her tour - the 72XXs are the last class of loco from Barry scrapyard to have not performed in preservation so she will be popular for the bigger lines. It's not without precedent either, No. 3822 spent a season at the Nene Valley many moons ago which is where she 'danced' on film with a certain Freddie Mercury and friends, but that's another story... With all of the fleet, you can expect at least her first season to be Didcot based.

 

As to power output, the cylinders on No. 7202 are machined close to the limit where the books say you have to fit liners which means she has oversize pistons. So she won't be a short of tractive effort - especially for the sort of running she will get in preservation...

 

All the best,

 

Castle

[Siberian Snooper]

I'd love to see one of these beasts actually steam in preservation.

[phil_sutters]

Dad's only photo of a 72XX, at Swindon after what must have been her last shop. 

[HowardGWR]

I'd love to see one of these beasts actually steam in preservation.

I suspect it will be very restricted in range of use.  They didn't like low radius turnouts.

Edited January 8, 2017 by HowardGWR

[Il Grifone]

omis

 

The GWR certainly didn't pander to the creature comforts of its footplate crews.

 

Churchward tried with a generous cab on 'Earl Cawdor', but received complaints from the workforce. They then got what they'd asked for....

 

Apparently, much the same had occourred previously when Matthew Kirtley fitted roofs (of miniscule dimensions) to Midland engines. Requests were received for their removal as enginemen of other railways were calling them "Cissies". The working class is often its own worst enemy.

[The Stationmaster]

Churchward tried with a generous cab on 'Earl Cawdor', but received complaints from the workforce. They then got what they'd asked for....

 

 

 

But not always - the valve gear on No.40/4000 was a source of considerable complaint until the engine was converted to a 'Castle'  while the Churchward 'Counties' were definitely not popular and the 'County Tanks' were the subject of official complaints.

[Western Star]

But not always - the valve gear on No.40/4000 was a source of considerable complaint until the engine was converted to a 'Castle'  while the Churchward 'Counties' were definitely not popular and the 'County Tanks' were the subject of official complaints.

Please tell us more about what was said, by whom, in relation to the County Tanks.

[Dunsignalling]

Although not a 72xx (obviously...) we had 4270 on the Mid Hants for a while. it could pull a house down but was by a huge margin the most uncomfortable engine I have ever driven. It felt like it was shaking itself to pieces at anything over 10mph, cramped cab with every control seemingly in an awkward place.

 

The GWR certainly didn't pander to the creature comforts of its footplate crews.

Not just the crew, when a 42xx was on the West Somerset for a while, if a driver gave it any "welly" up the banks, you really didn't want to be riding in the first two coaches, especially if trying to consume a cuppa without distributing most of it over table, floor, seats and self!

 

I'd think the "last resort" attitude to these locos and their stretched brethren being used on passenger duties in BR days was fully justified.  

 

John

Edited January 23, 2017 by Dunsignalling

[tomparryharry]

I seem to remember that the 42/52/72 had a slightly shorter buffer. This allowed the loco to 'jerk' a train from a standing start. The reduction in length is accomplished by reducing the width of the packing piece betwixt buffer beam, and buffer. By the same rule, you can increase the width, and allow for greater tightening of the coupling.

 

They didn't introduce SHOCVAN for nothing!

 

Ian

[The Stationmaster]

Please tell us more about what was said, by whom, in relation to the County Tanks.

 

Old Oak Common footplatemen made official complaints about them (and 4000) - and I have seen that in the notes of meetings.  But I don't know what the detail was although I suspect it might have related to rough riding and I know from conversations that they were definitely 'not liked'.

Edited January 23, 2017 by The Stationmaster

[Il Grifone]

The story goes that the Counties were Churchward's reaction to a LNWR ban on 4-6-0s on their metals. This is probably apocryphal, as it seems rather an extreme reaction and doesn't explain the County tanks.

 

Hind-sight (always 20/20) does suggest that large outside cylinders and a relatively short coupled wheelbase are going to result in oscillation at speed. (What the Italians call 'serpeggiamento' (snaking), though in their case from two cylinder compounds. One large and one small cylinder driving the same axle is another recipe for less than satisfactory running.)

Edited January 26, 2017 by Il Grifone

[DCB]

There is a reference in a book I read, I think it is "Through the links at Crewe" by "Picolo" Pete Johnson of a 72XX on a Crewe to Wellington? local after a failure.  It went "like a rocket" until the Vacuum pump linkage failed. It seems strange that the 42XX and 72XX surged fore and aft more than the 28XX when they were heavier and had 25Psi less boiler pressure unless it was ths short connecting rods but surely these should have created a vertical rocking rather than horizontal.

 

I always understood part of the rationale behind the 4-4-0 Counties was that the Midland banned 4-6-0s from the Bristol Gloucester line despite allowing Compounds which were GWR Double Red, and that some of the Counties last duties were on this line until the Midland allowed Hall and Castle 4-6-0s around 1931.

 

The County Tank seems to have been the passenger version of 99 the pioneer prairie which later became the 51XX class. The First County Tank  had the wide 31XX cab. I guess it didn't make any sense at all to make an "Atbara" tank so the standardisation logic created the un necessary non standard Counties out of standard Churchward parts, instead of the smoother running Dean era Standard parts.  

 

That said a model 4-4-2  tank based on a 61XX with City of  Truro frames should cause some head scratching.

[Il Grifone]

There is a reference in a book I read, I think it is "Through the links at Crewe" by "Picolo" Pete Johnson of a 72XX on a Crewe to Wellington? local after a failure.  It went "like a rocket" until the Vacuum pump linkage failed. It seems strange that the 42XX and 72XX surged fore and aft more than the 28XX when they were heavier and had 25Psi less boiler pressure unless it was ths short connecting rods but surely these should have created a vertical rocking rather than horizontal.

 

I always understood part of the rationale behind the 4-4-0 Counties was that the Midland banned 4-6-0s from the Bristol Gloucester line despite allowing Compounds which were GWR Double Red, and that some of the Counties last duties were on this line until the Midland allowed Hall and Castle 4-6-0s around 1931.

 

The County Tank seems to have been the passenger version of 99 the pioneer prairie which later became the 51XX class. The First County Tank  had the wide 31XX cab. I guess it didn't make any sense at all to make an "Atbara" tank so the standardisation logic created the un necessary non standard Counties out of standard Churchward parts, instead of the smoother running Dean era Standard parts.  

 

That said a model 4-4-2  tank based on a 61XX with City of  Truro frames should cause some head scratching.

 

G.J. Churchward insisted on horizontal cylinders to minimise vertical components in the motion, preferring an offset of the cylinder centre line. This must have still caused some vertical movement, I would have thought, but I've never bothered to solve the necessary vector diagrams....

 

That seems a logical explanation for the County tanks. It was only later that the 43xx moguls were added to the standard class list. I suppose there was still some of the 'freer running uncoupled axles' idea lingering,

 

I built an outside framed 4-4-2T once from the bits left over from a conversion of a 43xx from Kitmaster (that long ago!) 'City' and 'Prairie' kits. It must have ended up in the bin....

 

I thought it was the LNWR that objected to 4-6-0s, but it was a long time ago I read it. I'll have to try and track the reterence down. I only had about a dozen railway books at the time....  

 

Why were Midland compounds double red? or was it just that it took two of them to pull a train? Would the 1931 date have something to do with Sir William taking over and showing them how it was done?

 

(It's true this was actually 1/1/1932, but that would spoil the joke!)  

Edited February 25, 2017 by Il Grifone

[Gordon A]

There is good photograph of a 42xx leaving Bristol Temple Meads by Ben Brookbanks excellent site - https://commons.wikimedia.org/wiki/File%3ABristol_Temple_Meads_geograph-2542324-by-Ben-Brooksbank.jpg

 

Richard

 

Interesting that the left hand lamp above the buffer beam appears to be reversed ie lense facing the cab.

 

Gordon A