46235 City of Birmingham

Regarding the original paint argument, I recall this was used as a reason/excuse why 70013 would never steam again when it was displayed at Bressingham (I can confirm having read the garb myself at the time), so what changed there ?.

While I can understand many arguments for not steaming something, paint is not one of them, paint naturally fades with exposure to light and time, the condition cannot be preserved forever.

Also having viewed the various types plenty of times, I have trouble with the idea that LNER pacifics have better traction than their LMS counterparts, the Duchess never seems to lose it's feet as much as an A4.

 

From the company that brought you Black Fives and Jubilee's, rebuilt Scots & Patriots

 

Yep, it takes an expert to tell them all apart. Why change a winning formula?

 

There's more to paint than just colour though.

As an example, this is still visible on a carriage currently being restored in our C&W workshop. (Not my photo):

https://www.flickr.com/photos/extension3363/15258249226/in/album-72157626600437734/

If you zoom in, you can see lettering dating from 1880 saying "Each seat to hold 5 Persons".

In this particular case, the carriage will be restored and that will inevitably be painted over - but at least the size and lettering style is recorded. The difficulty is that it is not always obvious what information might be relevant in the future, but once it is gone, it's gone. That's not an argument for never restoring anything, but rather to think carefully before wilfully discarding what might be unique information.

Tom

 

Same with Dominion of Canada. There was a lot of arguments that she should have been left in BR Green because it was original paintwork applied by BR. However you could see how life expired it was when she was back here. It needed repainting touch ups alone would not have done the job. The engine was reborn when she was painted Garter Blue and had the bell refitted.

 

The other point is that46235 has been stored in good conditions indoors, other than her brief sojourne outside when being moved into Think Tank. The same can not be said of Dominion of Canada, Dwight D Eisenhower (the less said about her paint job prior to returning to the UK, the better...) or Oliver Cromwell. The latter, of course, was steamed regularly after going to Bressingham, which won't have helped either.

 

which GW locos *needed* 3 cyls or deflectors? Good designs see....

 

None because GWR locomotive development ended with Churchward.

 

I believe the answer lies in the valve gear arrangement. As I understand it, the Gresley Pacifics need to be notched in full gear at start-off in order to set-up the conjugated valve gear but then re-set to a lower point in order to accelerate; it is the rapid change from full gear to the lower gear which precipitates the slipping and is usually the sign of a driver not fully conversant with the driving technique required. Once on the move I believe that the A4 is more than capable of matching the Duchess's adhesion qualities given that the A4 is the slightly heavier beast by about a couple of tons.

 

I don't think so, Fred. Firstly, the main reason why LNER pacifics needed full gear, from my understanding, was an attempt to limit slipping by restricting maximum cut-off to 65% as opposed to the Stanier engines' 75%. Since the conjugated gear was fixed by pin joints, the valves for the middle engine would have to follow those of the outside cylinders; there should be no need to 'set' them. Secondly, the published weight of an A4 was 102T 19cwt, a Stanier pacific (without the extra weight of streamlining) was 105T 5cwt. This seems far more likely because of the sizes of their boilers: that from 60009 was joined in Bridgnorth Boiler Shop by that from 6233. Until then, the Bridgnorth boiler smiths had thought the A4 boiler was big!

 

Al, there's a lot of froth about paint, but surely another reason for leaving 46235 where she is is that to put her back on the main line would involve making substantial modifications to fit the present day loading gauge ., fit air pumps tpws/gsmr , low level water fillers and so on. Doubtless these are reversible, but traces would inevitably remain and would compromise its originality. We have two examples capable of running if the will is there and if funded, lets direct efforts into keeping one of these going and not mess up a third.

 

That makes a lot more sense to me!

 

4709 should be a good one for re-starting a heavy load even if only a class 7.

 

IIRC they were modified to 75% max cut off at a later date. I stand to be corrected though.

 

One

One of the few benefits of that horrible streamlining should be there are more places to hide all the electronic gubbins. Personally I'd love to have 46229 back as she was but fear that ship has now long sailed.

 

You're entitled to your opinion of the streamlining as "horrible", though many of us have the opposite view. But as for "as she was"; as she was when? Would you prefer the same principle as has been applied to Flying Scotsman, i.e. a close approximation to its appearance at the end of its BR career? If so, why? 6229's present appearance is a very close approximation to what it was when she first emerged from Crewe Works. Irrespective of liking or disliking it, that seems to me the most appropriate for a loco that (for the time being) will continue to sit beside Mallard in the NRM.

 

Yes, I believe you're right, but they didn't start off that way. I think it was because there were originally problems restarting from the curved platforms at York, but stand to be corrected on that.

 

Doesn't 3 vs 4 cylinders also come into it? I seem to recall some while back an analysis from @Steve that showed that although the torque at speed of a 3 cylinder design is more even than that of a 2 or 4 cylinder loco, at some positions of the pistons the available starting force at zero speed may be less - which would make starting more difficult, and may also lead to heavier use of the regulator with greater propensity to slip.

Tom