Smoke deflectors

Any aspect related to the structures and equipment on the Caledonian Railway Company.
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jimwatt2mm
Posts: 707
Joined: Fri Nov 16, 2012 5:36 pm

Smoke deflectors

Post by jimwatt2mm »

I am currently designing an etch for a model based on the footbridge from Dunblane, now at Bridge of Dun. This is for the 'Dunallander' layout started by the late Neil Ballantyne which is currently being completed by the Grampian Group of the 2MM Scale Association. A detailed survey of the bridge in its new location has been carried out, but two items which are no longer fitted to the bridge are the smoke deflectors which we think were removed after the demise of steam.

My question is, does anyone have details of smoke deflectors, width, profile and how far they might have projected beyond the sides of a bridge?

Jim W
dumb buffer
Posts: 518
Joined: Tue Aug 14, 2012 10:13 pm

Re: Smoke deflectors

Post by dumb buffer »

Jim

I have a drawing, from the CRA archive, of a signal bridge at Lesmahagow Jn, which shows the Smoke Deflectors, and should give you what you want. It's too big to attach here. If you PM me with an email address I could send it to you

Allan Ferguson
jimwatt2mm
Posts: 707
Joined: Fri Nov 16, 2012 5:36 pm

Re: Smoke deflectors

Post by jimwatt2mm »

Thanks for the drawing, Alan. Turns out it's to 4mm scale so easy for me to take dimensions off it! :D

Jim W
jimwatt2mm
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Joined: Fri Nov 16, 2012 5:36 pm

Re: Smoke deflectors

Post by jimwatt2mm »

I have now completed the model of Dunblane footbridge as it was c1960.
Completed #1 web.JPG
Completed #1 web.JPG (194.68 KiB) Viewed 11473 times
Completed #2 web.JPG
Completed #2 web.JPG (178.55 KiB) Viewed 11473 times
More photos at http://www.rmweb.co.uk/community/index. ... ?p=3311447.

Jim W
jasp
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Re: Smoke deflectors

Post by jasp »

Excellent!
Jim P
Jim Summers
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Re: Smoke deflectors

Post by Jim Summers »

You've certainly captured that, Jim.

JimS
dumb buffer
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Re: Smoke deflectors

Post by dumb buffer »

Very evocative, Jim -- but I need my dirty glasses!

I particularly like the subtle curve over the tracks. Did you do that
by building the structure in clear plastic, and sticking the planking etc on top?
Are you going to risk the wrath of the membership by putting an LNER loco under it?

Allan F
jimwatt2mm
Posts: 707
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Re: Smoke deflectors

Post by jimwatt2mm »

dumb buffer wrote:Very evocative, Jim -- but I need my dirty glasses!

I particularly like the subtle curve over the tracks. Did you do that
by building the structure in clear plastic, and sticking the planking etc on top?
Are you going to risk the wrath of the membership by putting an LNER loco under it?

Allan F
Hi Allan,

It's built from an etch from my own artwork. Full details of the build are in the RMweb link above. You don't need to be a member of RMWeb to view it, though you won't be able to comment there. The landing supports were 3D printed and the individual glazing was cut for me on a Silhouette cutter.

The model is not for myself, but is destined for a layout started by the late Neil Ballantine and being completed by the Grampian Area Group of the 2MM Scale Association, who provided me with detailed notes from a survey carried out at the bridge's new location at Bridge of Dun. As their time period is the late 1950's/early 1960's it may well get an ex-LNER loco passing under it! I will be handing it over to them for weathering at the 2MM SA AGM a week on Saturday.

Jim W
dumb buffer
Posts: 518
Joined: Tue Aug 14, 2012 10:13 pm

Re: Smoke deflectors

Post by dumb buffer »

Jim
Reading your RMWeb description doesn't diminish my admiration atall. I loved your description of how you got the latticework round the curve; and I still don't understand what a polar array is, though I can guess. I didn't realise the columns were 3D printed. It's good to see the latest hi-tech systems being used where they are the most appropriate.

Dare I raise a question? The prototype, both at Dunblane and at Brechin appears to have "see through" latticework, whereas the model is blanked off behind the lattice (which was, I think, sometimes done on the prototype, presumably for strengthening) Was this the rea?son on the model? I would guess that the naked latticework, in 2mm scale, would be exceptionally fragile, and difficult to keep straight during assembly. But then I expect such things of you...……

Allan F
jimwatt2mm
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Joined: Fri Nov 16, 2012 5:36 pm

Re: Smoke deflectors

Post by jimwatt2mm »

Alan. Thanks for the kind comments

Re. a polar array. An array is where the same object, or objects, are repeated at regular intervals. In a rectangular array they are in rows and/or columns. E.g. the doors and windows in a Dia 33 third could be said to be a rectangular array of 1 row and 8 columns. In a polar array they are arranged radially around a centre point through a specified number of degrees, e.g. the spokes of an 8 spoke wagon wheel form a polar array of 8 though 360°. Hope that explains it. BTW, I discovered that this was how the lattice was arranged across the central, curved section by a long period of trial and error, not through any expert knowledge!! :roll:

On the question of the solid area behind the lattice, this was how the bridge was originally build and remained at the time of the model. See https://www.railscot.co.uk/img/45/705/ . The footbridges at Crieff and Callander were similar, if not identical, in design. At some time between 1965 and 1985 https://www.railscot.co.uk/img/21/299 both the inner lining and the smoke deflectors were removed. Could this have been at the same time as the island platform building were demolished? Strength of the model was therefore not the reason. Had it been required as it is now I would have made it without the lining, though that might have required a different arrangement of the layers for the lower sections.

Jim W
Dave John
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Re: Smoke deflectors

Post by Dave John »

Stunning work in 2mm as ever Jim.
WCML55.68
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Re: Smoke deflectors

Post by WCML55.68 »

jimwatt2mm wrote:Thanks for the drawing, Alan. Turns out it's to 4mm scale so easy for me to take dimensions off it! :D

Jim W
Hello Jim,

Many years ago, I acquired several BR drawings of culvert deviation, works to the viaduct, alterations to the staff accommodation etc etc, which are now proving invaluable for the forthcoming Harthope Viaduct layout. They were all to different scales!!! Once the ratio was calculated for each plan to obtain the scale required, one of which was times 1.513 !!, a local printer and copiers who have a "wide format" scanner and printer fed the original in. Because of the length we both had doubts about the capability of the scanner as they had never done anything so long. I thought it was going to have to be done in sections and joined, creating its own set of problems, but paper not the problem as it runs off a huge roll of paper round the back. Like a giant loo roll. So purely down to the memory capacity of the scanner. Lets give it a try and see what happens he says. I could hardly contain excitement when an exact 4mm scale plan of Harthope Viaduct slowly appeared in its entirety on one sheet, saving a HUGE amount of work in rescaling and redrawing it and eliminating the possibility of any errors, and all for £2.50.........................................something smaller could be done by rescaling on home scanner.

Regards Paul.
WCML55.68
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Joined: Sat May 31, 2014 4:37 pm

Re: Smoke deflectors

Post by WCML55.68 »

Fabulous footbridge BTW.
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