Imaginary Locomotives

[The Johnster]

You'd have to have something a bit more effective than the HST yellow markers at the platform edges if you didn't want a rash of toasted commuters!

 

(Also its possibly probably DEFINITELY out of gauge...)

 

The American one didn't actually toast anyone AFAIK, but went like a stabbed rat, and with that amount of speed and power anything causing loading gauge problems would simply be hit harmlessly out of the way...

Edited October 31, 2017 by The Johnster

[Corbs]

 In some of the slugs, of course.  The pills are starting to kick in now...

Would that not make it a 'calf'?

Edited October 31, 2017 by Corbs

[runs as required]

The very first Garratt design, K1, did have the cylinders at the inner ends, this must have given some problem as the arrangement was never repeated. Possibly difficulties with arranging the pipes on larger engines as the cylinders would be inboard of the pivots.

Regards

I've enjoyed wasting a couple of hours exploring the innards of the WHR K1 Garratt. I am ashamed to admit that when I rode behind it some years ago, I never noticed that its cylinders were uniquely 'inboard', nor was I aware that it's the only compound BG.

I found this beautiful General Arrangement drawing on the web which I append

You can see the High Pressure 17" x 16" stroke cylinders are under the cab and the 11" x 16" Low Pressure cylinders are under the smoke box to discharge (via a complex joint) up into the blast pipe.

Above is an enlarged part shewing the arrangements around the large firebox and the boiler pressure 195 lbs/sq in steam pipe can be seen running from the dome down through the cab and into the forward part of the 'rear' engine via a complicated piece of asbestos wrapped 3" int. dia pipework closely related to the pivot before splitting to feed into the upper piston valves.

The cylinders exhaust below and the low pressure steam is sent forward in a 4" int. dia. pipe beneath the firebox to the low pressure cylinders.

 

In answer to my original question, I can see it must be quite roasting in the cab, and particularly complex to maintain being a compound with the pipework around the pivot.

The African Garratts had hugely long visible steam pipes running along IIRC under the footplating.

Is this OT? I suggest these beasts knock the spots off our own 'Imaginary Locomotives'

dh

 

Edit: I've just discovered a lot of Garratt complex steam pipes are currently being modelled on this thread

Edited November 1, 2017 by runs as required

[runs as required]

And here is an Algerian Garratt (the inspiration for that Ozzie jobby)

https://en.wikipedia.org/wiki/Garratt

In Algeria 29 4-6-2+2-6-4 Garratts, constructed between 1936 and 1941 by the Société Franco-Belge de Materiel de Chemins de Fer at Raismes in Northern France, operated until the Algerian independence war caused their withdrawal in 1951. This class, designated 231-132BT, was streamlined and featured Cossart motion gear, mechanical stokers and 1.8 m (5 ft 11 in) driving wheels, the largest of any Garratt class. On a test in France, one of these achieved a speed of 132 kilometres per hour (82 mph)—a record for any Garratt class (and indeed any articulated class).^[12]

 

^dh

[FPH 603]

Every time I go down to Thirlmere (for those who don't know, Thirlmere's in NSW) the AD60 class is one of my all time favourite locomotives. It's always so impressive to see, it's sheer size and power. A couple of years ago I went to the festival of steam and when we were getting to Picton, our train was joined by 6029, another AD60 class. Seeing one on static display is one thing, but seeing an operational one is another!

 

Edited October 31, 2017 by DoubleDeckInterurban

[FPH 603]

A Notice to all that have made the Pacer's look bad: I invite you to the all new We Hate Pacers Club! At the we hate Pacers club, we criticise how bad they truely are! We can make jokes about them, and do as we please. Follow us today if YOU hate Pacers. Brought to you by RMweb.

 

WARNING: I literally made a thread about this, and it turned to chaos, so DO NOT, I repeat DO NOT attempt to go to the thread and comment on it!

Edited November 1, 2017 by DoubleDeckInterurban

[Hroth]

A Notice to all that have made the Pacer's look bad: I invite you to the all new We Hate Pacers Club! At the we hate Pacers club, we criticise how bad they truely are! We can make jokes about them, and do as we please. Follow us today if YOU hate Pacers. Brought to you by RMweb.

image.jpeg

At one time I had to make a regular journey from Liverpool Lime Street to Wigan North Western, invariably on a Merseyrail Pacer service.  Taking about 50 minutes to make the trip (on a good day when the wind and rain were not against us), the sheer agony of that jolting cart must have taken years off my spine.  You may think you hate the rattletrap contraptions, but compared to my hatred, yours is but a mild disapproval!

 

Its a pity that the old Jeremy Clarkson Top Gear couldn't have done something with a pacer, instead of confining themselves to their mildly irrational dislike of caravans....  

[Northmoor]

The American one didn't actually toast anyone AFAIK, but went like a stabbed rat, and with that amount of speed and power anything causing loading gauge problems would simply be hit harmlessly out of the way...

Loading gauge might be a minor issue compared to entering anything resembling a curve.

 

Reminds me of the Darwin Award nominee who did something similar with a small jet engine and a Chevy.  IIRC the remains were found embedded about 50' up a cliff in Arizona, at the end of a long straight road..... 

[scots region]

The American one didn't actually toast anyone AFAIK, but went like a stabbed rat, and with that amount of speed and power anything causing loading gauge problems would simply be hit harmlessly out of the way...

 

Well, Harmlessly is a bit of an understatement isn't it? Still what's the odd footbridge user in the face of scientific progress? 

[Compound2632]

And here is an Algerian Garratt (the inspiration for that Ozzie jobby)

algerian garratt.jpg

https://en.wikipedia.org/wiki/Garratt

In Algeria 29 4-6-2+2-6-4 Garratts, constructed between 1936 and 1941 by the Société Franco-Belge de Materiel de Chemins de Fer at Raismes in Northern France, operated until the Algerian independence war caused their withdrawal in 1951. This class, designated 231-132BT, was streamlined and featured Cossart motion gear, mechanical stokers and 1.8 m (5 ft 11 in) driving wheels, the largest of any Garratt class. On a test in France, one of these achieved a speed of 132 kilometres per hour (82 mph)—a record for any Garratt class (and indeed any articulated class).^[12]

 

^dh

 

With such long steam pipes, any Beyer-Garratt must surely suffer from a considerable pressure drop between boiler and cylinders - not a recipe for efficiency, surely. Equally, the exhaust steam has a long way to get to the blastpipe. Hardly a free-steaming machine - the external streamlining would hardly compensate for the lack of internal streamlining. 

[34theletterbetweenB&D]

This picture of an Aussie Garratt style loco project prompts me to ask a practical question.

 

Why is it that Garratts had their outside cylinders at the outer ends of each engine rather than at the inner and thus much closer to the boiler?...

The extra toastiness adjacent the cab already mentioned might have contributed, but I suspect the main reason is dynamic. Direct drive steam locos inevitably have swaying couples as the off centre piston thrusts alternate. Positioned close to the pivot points this would result in harsh working on the pivots, with the actions directly transmitted to the bridge section. With the cylinders at the outer ends, the elasticity of the frames will damp out a proportion of these forces. I have had the joy of footplating a large Garratt being given all the beans to climb the Vic Falls escarpment (I in 39 or 2.5%) with about 1,500 ton behind it and the ride was 'vigorous'.

[Suzie]

I don't know what use the UK could find for this.....

 

HS 8000.jpg

 

I think that 8000HP would not be worth bothering with for a demonstrator - surely a 'B' unit would need to be put in the middle for a HS-12000

[PhilJ W]

Well, Harmlessly is a bit of an understatement isn't it? Still what's the odd footbridge user in the face of scientific progress? 

Apparently GT1 had a similar effect.

[Suzie]

Might be a popular export model so a North American bird name might help.

 

 

Same power as a pair of Centennials, but the smaller bogies might help it go anywhere too.

 

 

[brack]

With such long steam pipes, any Beyer-Garratt must surely suffer from a considerable pressure drop between boiler and cylinders - not a recipe for efficiency, surely. Equally, the exhaust steam has a long way to get to the blastpipe. Hardly a free-steaming machine - the external streamlining would hardly compensate for the lack of internal streamlining.

External streamlining is all about fashion than function, it's true that long pipes aren't ideal, particularly on a compound (hence only the Tasmanian k class and the Burma design were built as compounds) and the earlier Garratt steam joints and ports were not great in terms of internal streamlining (later designs were much better in that regard, as understanding improved), but the optimal boiler shape and firebox dimensions you get as a side effect of the design are far superior to those possible on a conventional loco - the firebox has nothing to go around or below it and the boiler ends up short and fat, with a much greater proportion of the heating surface closer to the firebox. Hence garratts generally had a reputation for steaming well, plus beyer, peacock build quality was usually pretty good. The speeds at which most articulated locos worked (several classes have been recorded at 60mph+, but if you need an articulated loco your line might not be conducive to high speed running) probably kept piston speeds at a level whereby internal streamlining didn't have that much of an impact on performance and any deficiency in that area was hidden by excellent boiler/firebox characteristics, good valve gear design and the smoothness inherent in a dual bogie 4/6/8 cylinder loco. There are more troubles recorded with garratts running too fast for the track or services they were on than of choking off steam supply at speed.

[runs as required]

... I have had the joy of footplating a large Garratt being given all the beans to climb the Vic Falls escarpment (I in 39 or 2.5%) with about 1,500 ton behind it and the ride was 'vigorous'.

I do envy you that climb up the escarpment; they were too worried about the war in the Zambesi valley while I was there to trust strangers, there was a high rate of sabotage 'incidents'.

But I did invited onto both Zambian Garratts and the smaller EAR ones in Tanzania at customary slow speeds and recall the ride as smoother than conventional outside cylinder African steam types.

EAR maintenance of their Garratts was excellent at the time I worked in East Africa - they were also beautifully turned out in lined crimson lake. Wish I could lay my hands on some old transparencies of these.

dh

[Satan's Goldfish]

Might be a popular export model so a North American bird name might help.

 

HS-12000.jpg

 

Same power as a pair of Centennials, but the smaller bogies might help it go anywhere too.

 

 

I had thought about that, but it was enough hassle creating a single ended version and then couldn't be bothered (Good naming choice btw). To me it looks to have a similar visual presence as an F unit A-B-B-A set and would look very good at the head of a long US freight. Probably needs regearing slightly for slower speeds, but that's just going to boost the tractive effort further.

Edited November 1, 2017 by Satan's Goldfish

[Suzie]

If the Heljan models were not so expensive it might be a fun one to make. There is a lot of modelling of 'what might have been' locos in the American H0 scene to match fictitious locations and operators.

[Satan's Goldfish]

It's beyond my basic ms paint skills, but can somebody graft Kestrels cabs and roof profile onto a DMU to see how that looks? could make a faster replacement for the blue Pullman.

[Wolseley]

Every time I go down to Thirlmere (for those who don't know, Thirlmere's in NSW) the AD60 class is one of my all time favourite locomotives. It's always so impressive to see, it's sheer size and power. A couple of years ago I went to the festival of steam and when we were getting to Picton, our train was joined by 6029, another AD60 class. Seeing one on static display is one thing, but seeing an operational one is another!

 

image.jpeg

 

 

Not a very good photo I'm afraid (I might try scanning the slide again to see if I can get a better copy out of it) but here I am in 1976 or thereabouts with 6042 at Summit Tank, on the Moss Vale-Unanderra line, on the occasion of a NSWRTM tour, which used 3801 as far as Moss Vale.

 

[scots region]

If the Heljan models were not so expensive it might be a fun one to make. There is a lot of modelling of 'what might have been' locos in the American H0 scene to match fictitious locations and operators.

One idea that occurs is what would we have gotten if BR had decided to nix domestic production altogether and just buy from America or the continent. Or manufactured designs under license.

[Satan's Goldfish]

One idea that occurs is what would we have gotten if BR had decided to nix domestic production altogether and just buy from America or the continent. Or manufactured designs under license.

 

I think some of the Irish classes fall into that bracket.

[PhilJ W]

On another thread which discusses modelling preserved railways someone suggested modelling a preserved GWR broad gauge line. He also suggested for ECS and other non-passenger duties a broad gauge class 08 with the wheels outside the frames. I wonder if any more diesels and electrics could be so treated.

[Suzie]

I give you the HS120 'Wagtail' 125mph high speed DMU 4-car demonstrator. Twin power cars with 2000HP each. Traction motors are one per bogie on power cars and adjacent trailer cars to spread the weight (and to save me having to find more appropriate bogies!) just like the Blue Pullman. Should make a nice 8-car set in normal operation.

 

 

Just give me a time machine and send me to the Brush drawing office! Who could possibly resist...

[Suzie]

If Kestrel had not come in overweight probably more likely that we would have seen loco hauled push-pull sets for 125mph operation with Kestrels on one end and driving trailers on the other.