Garratt for sale !

Exactly. If you're going to the expense of new frames, boiler and superstructure, why be a cheapskate and re-use the wheels, motion and cylinders? Do it right the first time - don't compromise. Build new wheels and motion with roller bearings throughout, cylinders designed to be an exact match to the boiler's steaming capability and with steam passages streamlined, and hopefully within loading gauge to run on nearly any 600mm line.

Depends really. If you really wanted to buy a '16, restore it and use it, there aren't many options left. 115 is supposed to be even worse than 130, and they're the only two available in the UK right now. Most of the non-servicable '16's in South Africa are in the same condition. Sandstone have several, but judging by the pictures of the ones they recovered from Port Shepstone a few years ago (152 was one, I can't remember off-hand the other two) they're even bigger restoration jobs than any of the Exmoor machines. 139, 151 & 156 may still be available, but i've not heard anything on these two since 127 got shipped off to Australia.

For my money, i'd buy 130, and instead of splurging money replacing like for like, modernise it. See how efficient we could make an NGG16. If it needs major boiler work, no problem. Ideal time to try GPCS over here, and see if we can improve on the 16/A's. Pipework all missing? Fine. Replace with a new setup, designed for maximum efficiency. Superstructure replacement is a non-issue - 87, 138 & 143 have all had new cabs & bunkers, and 138 at least has had a new tank, all in the last 15 years.

Of course, i'd really like to see 141 or 155 (both now at Sandstone) in steam again, but they are both a long way in both funds and time from being back in steam.

 

Yes that had occurred to me too. Odd, interesting little Victorian industrial. Surprised Beamish didn't snap it up!

 

I'm not saying don't do it. I'm just saying be prepared to spend a lot doing it.

I can't help but feel that making the reciprocating steam loco 'efficient' is something of a dead end. They are an inherently inefficient concept and should be embraced as such. Fitting a firebox with holes in and a funny exhaust pipe will not make a 1927 designed steam loco efficient. It will just make it slightly more efficient than an unmodified equivalent. Changing things to improve the reliability, ease operation or to cure steaming problems I am all for as these can have a real effect on cost in the long term. After all things like the top feed axle boxes on these locos are somewhat stone age. Realistically though any improvements in efficiency will be swallowed by the quality or otherwise of the loco crew. This can vary quite a lot on any preserved railway.

 

I quite agree - improvements shouldn't just be centered around getting x more miles per ton of coal consumed, though obviously reducing the fuel bill is always helpful. Good crew training and good handling of the machine can yield much improved performance over a poorly trained crew. Roller bearings wherever possible, and other enhancements to improve reliability will all go towards improving how the loco performs.

If you want a truly modern machine, design and build from scratch - learning from the weak points of previous machines, is the only way to build without restriction or compromise.

However, that is no reason to not look at improving what already exists. If I remember correctly, 87 has a Lempor blast pipe, so no apparent need for external alterations. Next time i'm at BL i'll check - if so i'd like to know if it has offered any improvement in any way over 143 (which I think has a standard blastpipe arrangement).

Cost? If it were me, i'd budget £750k with a 10% contingency fund on top. Big numbers, but thats what these things cost.

 

Back to that 'why not build a 2-6-2 tank out of a Garratt power bogie' question. The official line is that by the time you'd added an ashpan, cab and bunker on the back, the thing would be so arse-heavy that you'd need to take off the rear pony truck and hang a new four-wheeled one off the back of the frames to get the weight distribution right. Not worth the effort, was the verdict.

 

There's actually 3 railways you could run an ng13/16/15 on:
The Welsh Highland railway as stated.
The Brecon Mountain railway.
The Vale of Rheidol railway.
So there not just suited to the WHR yes they might not fit in with the VofR but they could still be used and the WHR doesn't need any more motive power in the steam department, it needs a new diesel loco and more coaches. If the ng16s at Exmoor are not worth restoring in there own right they could be used as spare parts make a good set of bogeys and a boiler out of the two, im sure the WHR would love to have a set of bogeys that could be swapped in a day than having the whole loco out of action for months while work is done. I know that its easier to start from new but there simply isn't the money or time to do that as you need drawings, forgings then months of machining to do instead of getting a rusty one, cleaning it up making a pair of new bushes, possibly straighten it and there you go a new rod or cyclender.
thanks
Patrick
Oh i like the idea of an ng16A MK2 but its still an if i win the lottery dream.

 

Unfortunately spare bogies would not be universal - 1951/58/68 bogies are slightly different to previous builds, in terms of lubrication and pivot adjustment. Obviously alterations are possible, but it rather defeats the easy swap idea.

The boilers on both 115 and 130 are pre-war boilers - for 115 this is fine, as it is a 1939 machine, carrying No. 8384 of 1928. However, 130 was built in '51, so I don't know how heavily the boiler (No. 8787/1936, first carried by 88) or the rest has been altered to take account of the difference in fittings. 143 currently carries boiler No. 9061 which is a 1939 boiler (originally carried by 110), but has been altered during an overhaul in South Africa to postwar spec apart from the top feed mount just in front of the dome, which is not an issue as far as fitment to a postwar machine is concerned.

I think you're also a bit optimistic with the 'clean, make new bushes and there you go' way of overhauling - it's several months work in itself to overhaul an NGG16 power bogie, and even the small stuff takes time to refurbish.

 

If I had the money I'd be interested. Something a bit different.

 

Patrick,
I'll pass on your advice to the works manager and the board. Thanks.

 

Drawings at least shouldn't be a problem - they are available at - SAR Steam, along with those for just about every other class of SA steam loco (there's around 200 sheets of drawings for the NG16, ~270 for the NG15).

 

Sadly a scientific test has never been done. But as both locos are not in the same condition it wouldn't really be a fair test anyway. Really you would want to test 87 with normal and lempor blast pipes, and do it on the same day with the same load, crew, route, coal etc. Basically what was done with Merddin Emrys a few years ago.

 

It's an interesting story. 3 Garratts were supplied to NZR. They were a 6 cylinder design with Gresley compensated valve gear driving the middle cylinder, 4-6-2+2-6-4 wheel arrangement and about 58,000lbs TE at 85% boiler pressure - on the NZ gauge of 3'6".

Sadly, in service, they proved little short of disasterous. The TE was so great that the standard wagon draw gear of the day couldn't cope with the traction forces. Passing loops at stations weren't long enough to cope with the size of trains the locos could theoretically pull (assuming the wagons hadn't broken up first!). The NZ mining industry at the time couldn't produce well graded coal suitable for the locos' mechanical stokers. And to add insult to injury, the Gresley valve gear proved a nightmare to keep maintained in service conditions, so that the valve events of the centre cylinders went to pot unless large amounts of time was spent in maintenance. As such, the locos only ran about 12,000 miles per year on average in their first incarnation - against average mileages about four times that from the K class locos that replaced them.

Eventually enough was enough and they were rebuilt into 6 conventional pacific type locos. However, they were little better, and can only really be considered even as good as "adequate" if the criterion was "were they better than the Garratts?" The high mounted centre cylinder forced by having drive to the middle axle was not a problem on the Garratt design, but on the pacific it forced a high mounted boiler. This in turn was too small (so as to fit the loading gauge) for the cylinders, so the locos were always short of steam. Add to that the problems with the conjugated valve gear were never solved, and there were a host of more minor problems (poor regulator design, poor sanders etc) which meant the locos were always, at best, "tricky" and expensive (and unpopular) to work on. They did nonetheless soldier on until 1956, before disappearing when diesels reached the South Island. Probably their best feature were the new tenders, which were reused on the A[sup]B[/sup] pacifics.

Photo as a Garratt: Garratt
Photo as a Pacific: G Class 4-6-2

Tom

 

Such "before and after" tests were done with members of the W&LLR fleet and established beyond doubt that Lempor is a "good thing". Nowadays it is de rigeur on that line.

I seem to recall Chapelon established that improvements to small parts of the steam circuit in isolation did not produce much improvement. Could the rather convoluted steam piping of a Garratt contain more than its share of bottlenecks?

For those interested Martyn Bane's Steam and Travel Pages contain a great deal of relevance to this issue.

P.H.

 

Of course it would but it is comparing the wrong thing. A modern Lempor designed with all the tools and knowledge of fluid dynamics we have now will always trump some 1900's rule of thumb bit of pipe pointing vaguely in the right direction. Or indeed anything from Romania. I expect the improvement is lessened somewhat if you compare it to a well designed simple blast arrangement. After all just getting your chimney the right shape can give a huge improvement.

 

It may well be so but just as we must beware of something new just because it is new, so we must beware of "not invented here".

PH

 

Wow - fascinating photos. Wonder if the LNER U1 was the inspiration for these, as they were built just 3 years later? Amazing to see the conjugated gear just hanging out front in the fresh air on the rebuilds, unless they had a cover like the original and it had been removed, but doesn't look that way to me.

 

Only for the 1958 batch though. There are several hundred more that are specific to the 1936, 39, 51 & 68 batches. If I remember correctly the drawings for the 1958 batch were a complete new set, with none carried over from the '51 batch. Thats not to say the drawings are of no use however as 138, 140 & 143 are all '58 batch machines, though of course the F&WHR hold a complete set of drawings for them already, as well as the drawings for the 1936 Cockerill batch.

Of course - the only way to be certain of any improvement is to test both configurations in a variety of circumstances.

I would hope that most steam engines recently overhauled in the UK have at least got good condition, well-aligned blastpipes. It would be interesting to pit a factory-spec blast pipe arrangement manufactured to modern standards against both a standard blast pipe that has had years of wear and tear and a modern setup designed with all the tricks and tools at our disposal.

However the blastpipe is not the only part that needs improving, realistically everything in the steam circuit needs to be designed for efficient, smooth flow and to get steam to and from the cylinders as fast as possible with minimum loss. With the tools available to us today there is no reason in my mind to keep plodding on with an old component that is inefficient. It may have been the best that an engineer in 1928 could do, but we can, and should, do better. A great example are the piston-valve bogies now being built at Boston Lodge for David Lloyd George - whilst piston valves aren't exactly new technology, they are a significant improvement. They will also hopefully allow DLG to perform as designed.

Working, limited-use museum pieces like Palmerston are excusable from the march of progress, and it is right that engineering and technology from every period is showcased and preserved for future generations to see and experience, but there is no reason why machines in revenue-earning everyday use such as the NGG16's on the WHR should not have inherent faults and restrictions re-engineered out of them as funds allow.

D. Wardale's book 'The Red Devil' is rather enlightening on the subject - and as you say, test, test and test again is the only way to define the difference between different setups.

 

A photo I have from August 1939 (the rebuilding took place in 1937-38) shows G95 with a cover over the rocking lever in the same way as they had in Garratt form. However, all the other photos I have seen from after that date show the rocking lever uncovered. I suspect (but don't know) that so much maintenance was involved that the shed staff found it easier to leave the covers off permanently.

As for the 6 cylinder form: It seems in the mid-1920s, there was a Royal Commission into the railways of NZ, led by Sir Sam Fay (who at that time was chairman of Beyer-Peacock) and Sir Vincent Raven. Raven was a proponent of 3 cylinder designs, and between them, they recommended Garratts for the North Island Main Trunk, and 3 cylinder conventional locos elsewhere. At that time, the CME of NZR was Fay's son-in-law, and, coming from England, had little experience of local operating conditions. He thus combined the two proposals to specify a 6-cylinder Garratt and placed an order with Beyer Peacock in January 1928. The rest, as they say, is somewhat unfortunate history...

Incidentally, and OT - for more information on these locos and other NZ oddities such as the 6 H class "Fell" locos, the best work is "The NZR Steam Locomotive" by Sean Millar - ISBN-13 9780908573899

Tom

 

..personally i can't stand them but i know most of you do so have a look at this, if you do have a problem with the link it does take a while, go for the second line down second button in from the left....Railway collections-http://railway-collections.blogspot.de/#!/2012/08/blog-post_5458.html...

 

..and there's more take a look around on the site.http://railway-collections.blogspot.de/