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Pragmatic Pre-Grouping - Mikkel's Workbench


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One thing this picture shows is that there’s just one guage glass on this class, most modern locos have two , one either side. The back up in this case is that there are two very small trycocks just to the right of the gaugeglass, you can open them and get steam out of one, and hot water out of the other if you’re in luck. The sander levers also had a habit of rising out of the floor somewhere.

All great western locos only have one gauge glass
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All great western locos only have one gauge glass

Um, wrong.  You can see only one on the boiler.  There could be up to aniother four glasses in a wooden block in one of the toolboxes (generally).  Enginemen were expected to be able to change a broken glass whilst an engine was in service.

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I think these are what Mike is referring to shown on my photograph of the DG at Steam, Swindon

 

attachicon.gifDG Cab.jpg

 

G

The one thing that puzzles me is the fact that the driver has to stand astride the reversing lever quadrant? That must have made the driving position very awkward when the lever was pulled towards the back!

 

Tim T

Modelling Cwm Cynon in EM

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Um, wrong.  You can see only one on the boiler.  There could be up to aniother four glasses in a wooden block in one of the toolboxes (generally).  Enginemen were expected to be able to change a broken glass whilst an engine was in service.

spare glasses hardly qualify in the context of my reply. Okay. All GWR locomotives, unlike most others were only fitted with ONE water gauge.
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Very informative posts, learning a lot. Including which end of the loco to look at  :D

 

 

Really like the Dean goods, Mikkel. I've read through the thread the past month or so, and so I wondered how long it would take you to get started again. The baseboard sawing looks a bit brutal.

 

Thanks Charlie. Yes the baseboard sawing was a bit brutal, but it ended OK. The layouts are now much more manageable. The plan is to operate them from a single portable traverser. 

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You youngsters need to look back into Broad Gauge history!  As noted above, you are looking at the wrong end of the engine, Mikkel, in terms of 'dampers'.  These are along the leading and trailing edges of the firebox ashpan, to admit air when running either forwards or back - the controls are usually levers rising up from the cab floor.

 

If you look at the drawing in my blog of a Waverley-class 4-4-0 http://www.rmweb.co.uk/community/uploads/monthly_01_2018/blogentry-19820-0-38137800-1515088723.jpg you will see the lever on the side of the smokebox, which is for operating the blower.  (It's one of the many 'fiddly bits' that I still have to attach.)  The Martin Finney kit instructions  for 'Rover' also show and name this part.  There is a shaft from the lever on the side of the smokebox to the blower ring valve on the blast pipe.

 

Mike

I had thought that it might be the linkage for the blower valve, but couldn't understand why you would put the valve in the rather hostile environment inside the smokebox with the operating which needed a good seal passing through into the smokebox. .

 

The LNWR mounted the valve outside the smokebox operated by rotating a shaft (which sometimes doubles as the handrail). The blower steam pipes, easier to permanently seal, passed through the smokebox wall.

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The lever on the left hand side of the smokebox (looking from the cab) is a manual control for a variable blast pipe and precedes the Churchward jumper ring (which was automatic in operation).  Look for "Maclellan variable blast pipe" using your favourite search engine.

 

The steam cylinder on the lower right hand side of the smokebox was a Churchward device to reduce the gas flow through the tubes when the regulator was closed...  or more to the point, to reduce the burning effect of hot gases on the return bends of the superheater elements when there was no steam passing through the elements (the purpose of the elements being to raise the temperature of the steam passing through them means that the steam is a cooling influence on the elements)..

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The LNWR mounted the valve outside the smokebox operated by rotating a shaft (which sometimes doubles as the handrail).

 

I think the GWR also adopted rotating handrails (or something rotating inside a hollow handrail), judging by the compact size of some of the devices adjacent to the smokebox.

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The steam cylinder on the lower right hand side of the smokebox was a Churchward device to reduce the gas flow through the tubes when the regulator was closed...  or more to the point, to reduce the burning effect of hot gases on the return bends of the superheater elements when there was no steam passing through the elements (the purpose of the elements being to raise the temperature of the steam passing through them means that the steam is a cooling influence on the elements)..

 

Thanks. I feel suitably empowered to continue to call it a smokebox damper, and I now know what it does and why it does it.

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I think the GWR also adopted rotating handrails (or something rotating inside a hollow handrail), judging by the compact size of some of the devices adjacent to the smokebox.

Yes. The handrail was hollow with an operating rod running through. By no means unique to the Great Western, it was a common ploy for operating various valves, etc.
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Now I'm confused!  I agree with Western Star and had just found the description of the Churchward superheater damper in Holcroft's 'GW Locomotive Practice', when he posted.

 

Unfortunately, I then read a bit more of Holcroft and he states that "with the appearance of the Iron Duke class ....owing to the width of the firebox back, a pull out lever was arranged for the grid type regulator on the front of the smokebox tubeplate and brought control within easy reach of the driver.".  It seems that this may be the lever I have been looking at on the early BG engines. 

 

The Finney model is of the later Rover or Alma-class rebuild and, although the fitting is in a similar position, it looks as though the blower valve is a larger fitting on the outside of the smokebox.

 

So, it's probably just a coincidence that the lever on the Dean Goods looks similar to the old BG fitting.  For my Rob Roy model, I'll simply fit the lever and not worry too much about what happens inside the smoke-box.  I'm clearly too far back in the really old days :)

 

Mike

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Well, I did consider fitting these to my current ongoing 7mm build but found no evidence so I've left them off.

 

Bodies temporarily fitted, as are the top fittings but ran without any issues !

 

 

Grahame

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That's a real beauty Grahame. I do like the tender.

 

 

I agree.

Tell us more!

 

 

Thank you both, much appreciated.

 

I won't take up Mikkels' thread with long winded details that would be unfair, although I did consider a Blog but then even that would impinge upon my time sadly.

 

That said, brief summary, its a Warren Shephard 7mm brass kit of a basic Dean Goods with a choice of tenders, either the 2000 gallon or 2500 / 3000 gallon types.

 

It is modelled as locomotive no. 2398 ( still awaiting some Finney7 numberplates to arrive ) which ran with a 2000 gall. tender and she was based at Bristol.

 

The tender ** has proven to be a slight stumbling block in the build as it didn't have a water scoop fitted which meant several areas needed to be thought about when building but I think its there now.

 

The main reason for that tender, relative to your comment Mikkel, is that it also saves a few inches on the proposed layout which will be a West Country theme so I can say that if it runs on it then it has a right to be there as opposed to further up the GWR system ( thats my story and I'm sticking to it !!! ).

 

I hope that gives you a very brief precis.

 

It is my very first 7mm build and most enjoyable / frustrating / etc etc . Worth doing ? Definately, would I build another ? Yes but maybe another version or manufacturer.

 

The build was very much inspired by Wenlock ( Dave ) of this parish when I saw his Dean Goods running at the SWAG meeting in Taunton a couple of years ago on his superb layout Sherton Abbas...its ALL his fault ! LOL !

 

I am now totally sold on O Gauge and will continue, the next build will be a Scorpio kit Armstrong Goods.

 

G

 

** Although a GA Drawing is supplied with this kit for the 2000 gall. tender and shows a water scoop I did question it with Warren ( who I might add is an extremely nice, helpful chap ) and strangely, although he produces it didn't have an answer to my question ref this and two handles - one for the scoop and the other for the brakes, and associated undergubbins. Therefore please do your research wherever possible if building a 2000 gall tender as photographs and information is very scarce ( With thanks to Miss P. and Castle of this parish ).

Edited by bgman
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Thank you Miss P. I saw that some while ago and enjoyed it, however, it never ceases to amaze me how the cameraman manages to run alongside without falling over !  :O

 

G

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Thanks for asking. Just a bit of re-wiring to do now (famous last words!). I got distracted by a search for storage boxes for them, as per Paul's latest creations here. However they are all either too short or too narrow. 

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