Junctionmad Posted February 28, 2019 Share Posted February 28, 2019 Gas anyone got the basic dimensions of a simple GWR tubular signal, diameter of the post/tube etc , I have drawings of the complex complex types but no basic dimensions of a simple signal (nor does the internet reveal anything ) thanks dave Link to post Share on other sites More sharing options...
RMweb Gold The Stationmaster Posted February 28, 2019 RMweb Gold Share Posted February 28, 2019 There is an official drawing in Vaughan's book which shows a dimension for the dolls on a bracket structure which as far as I know from up close study of them would be the same as ordinary straight post signal above the shoulder in the tube - it says 5.5" outside diameter. Quite possibly it was 6" nominal outside diameter tube because it would inevitably have been a stock size. The bit I don't know is the diameter below the 'shoulder' but it shouldn't be too difficult to find one to measure (with permission of course) on a heritage railway. One challenge - which I think Dapol solved with their tubular post signals - is getting the proportions looking right between the two different diameters. 1 Link to post Share on other sites More sharing options...
Miss Prism Posted February 28, 2019 Share Posted February 28, 2019 5.5" was I think a stock size. I don't know the lower diameter either, but I'm guessing 6" on the basis of a probable 0.25" wall thickness. (Mike's quite right - someone ought to measure one and do a drawing.) 1 1 Link to post Share on other sites More sharing options...
bécasse Posted February 28, 2019 Share Posted February 28, 2019 LMS tubular posts should, in theory, have been built to the same dimensions. These varied very slightly according to date, but for 4mm or 7mm modelling purposes taking the two diameters as 5,5 ins and 6,5 ins would suffice as the variations would fall well within the thickness of a model's coat of paint. Link to post Share on other sites More sharing options...
Junctionmad Posted March 1, 2019 Author Share Posted March 1, 2019 I’ll look through Vaughan’s book again , yet I dint see any simple diagrams , I would have thought brackets would have thicker tubes Link to post Share on other sites More sharing options...
Junctionmad Posted March 1, 2019 Author Share Posted March 1, 2019 (edited) 12 hours ago, The Stationmaster said: There is an official drawing in Vaughan's book which shows a dimension for the dolls on a bracket structure which as far as I know from up close study of them would be the same as ordinary straight post signal above the shoulder in the tube - it says 5.5" outside diameter. Quite possibly it was 6" nominal outside diameter tube because it would inevitably have been a stock size. The bit I don't know is the diameter below the 'shoulder' but it shouldn't be too difficult to find one to measure (with permission of course) on a heritage railway. One challenge - which I think Dapol solved with their tubular post signals - is getting the proportions looking right between the two different diameters. The Dapol signal has the shoulder well up in the top 2/3 of the pole, was it that high ? Pictures of the real thing show the shoulder in the bottom 1/3 Edited March 1, 2019 by Junctionmad Link to post Share on other sites More sharing options...
Junctionmad Posted March 1, 2019 Author Share Posted March 1, 2019 6 minutes ago, Junctionmad said: The Dapol signal has the shoulder well up in the top 2/3 of the pole, was it that high ? Pictures of the real thing show the shoulder in the bottom 1/3 or the shoulder around ½ height https://www.wizardmodels.ltd/shop/signals/s7_kw2/ Link to post Share on other sites More sharing options...
RMweb Gold The Stationmaster Posted March 1, 2019 RMweb Gold Share Posted March 1, 2019 11 hours ago, Junctionmad said: The Dapol signal has the shoulder well up in the top 2/3 of the pole, was it that high ? Pictures of the real thing show the shoulder in the bottom 1/3 Depends on the total height of the post. No doubt Reading had a standard ratio for it! Link to post Share on other sites More sharing options...
micknich2003 Posted March 1, 2019 Share Posted March 1, 2019 The LNERly and LMSRly drawings I have show the signal post to be 5 1/2 in dia and the butt 6 5/8 dia. Shorter signals, that is up to 20ft have 6ft "Butt", all taller signals have 10ft Butt, all measurements are above rail height. Admittedly not GWRly, but probably the same dimensions and bought in from the same steel mill. Link to post Share on other sites More sharing options...
Junctionmad Posted March 1, 2019 Author Share Posted March 1, 2019 Given the preponderance of gwr modelling over the years , I’m always surprised how little info there is online Link to post Share on other sites More sharing options...
RMweb Gold The Stationmaster Posted March 2, 2019 RMweb Gold Share Posted March 2, 2019 15 hours ago, Junctionmad said: Given the preponderance of gwr modelling over the years , I’m always surprised how little info there is online Or anywhere else!! 1 Link to post Share on other sites More sharing options...
Miss Prism Posted March 2, 2019 Share Posted March 2, 2019 There was a well-illustrated multipart article on GWR tubular post signals in the Railway Modeller way back. c 1966 ??. It was an extremely good article, although (iirc) perhaps lacking on some dimensional details. 2 Link to post Share on other sites More sharing options...
Terra-Nova2 Posted March 2, 2019 Share Posted March 2, 2019 Dear Junctionmad Issue 47 of the Great Western Railway Journal has an article with drawings on GWR tubular signals. A quick scan before sending this looks like it will have what you want Link to post Share on other sites More sharing options...
Terra-Nova2 Posted March 2, 2019 Share Posted March 2, 2019 Oh and I forgot to add the short answer is 6 1/2 inches diameter for the first 12 feet from rail level followed by 5 1/2 inches diameter. Spindle 12 inches below base of finial. There are loads of other dimensions in the article 1 Link to post Share on other sites More sharing options...
RMweb Gold The Stationmaster Posted March 2, 2019 RMweb Gold Share Posted March 2, 2019 8 hours ago, Terra-Nova2 said: Oh and I forgot to add the short answer is 6 1/2 inches diameter for the first 12 feet from rail level followed by 5 1/2 inches diameter. Spindle 12 inches below base of finial. There are loads of other dimensions in the article Is that for a 17ft 6" signal. (distance of the arm horizontal centre line above rail level) or a taller one? Link to post Share on other sites More sharing options...
Junctionmad Posted March 2, 2019 Author Share Posted March 2, 2019 Thanks for info Dave Link to post Share on other sites More sharing options...
Terra-Nova2 Posted March 3, 2019 Share Posted March 3, 2019 17 hours ago, The Stationmaster said: Is that for a 17ft 6" signal. (distance of the arm horizontal centre line above rail level) or a taller one? There are two single post drawings One is a 23' Stop and Distant Signal and the other is an 18' Stop only and both have the wider dimension for 12' above rail level But I guess this may be one of those things where the draftsman's assumption and reality may be different ! Link to post Share on other sites More sharing options...
Stephen Freeman Posted March 3, 2019 Share Posted March 3, 2019 20 hours ago, The Stationmaster said: Is that for a 17ft 6" signal. (distance of the arm horizontal centre line above rail level) or a taller one? I've always gone by the figures quoted by MSE, which do state that the butt is always 12ft above rail height. Diameters of tube etc as above. Link to post Share on other sites More sharing options...
Junctionmad Posted March 3, 2019 Author Share Posted March 3, 2019 Its seems 12’ to the necking point was the standard dave Link to post Share on other sites More sharing options...
Junctionmad Posted March 3, 2019 Author Share Posted March 3, 2019 Using Albion alloys , I think I’ll approximate to 4mm and 3mm for the base and top tubes interesting I gather the tube was never drilled except for the top finial , all fittings being of various clamp style Link to post Share on other sites More sharing options...
Junctionmad Posted March 3, 2019 Author Share Posted March 3, 2019 The other missing bit is a close up photo of the balance arm bracket on tubular posts , it’s difficult to discern in many photos as it’s rather lost in the “ black” Link to post Share on other sites More sharing options...
Stephen Freeman Posted March 4, 2019 Share Posted March 4, 2019 Does this help? 2 Link to post Share on other sites More sharing options...
Gordon A Posted March 4, 2019 Share Posted March 4, 2019 In Adrian Vaughn's book Great Western Signalling the only tube diameters I can find quoted are for the early colour light signals, which is shown as 5 1/2" and 6 1/2 ". Another diagram refers to the posts as "standard posts". Anything with brackets appears to have a main post made of I girders. Gordon A Link to post Share on other sites More sharing options...
RMweb Gold The Stationmaster Posted March 4, 2019 RMweb Gold Share Posted March 4, 2019 22 hours ago, Terra-Nova2 said: There are two single post drawings One is a 23' Stop and Distant Signal and the other is an 18' Stop only and both have the wider dimension for 12' above rail level But I guess this may be one of those things where the draftsman's assumption and reality may be different ! The normal dimensions for tubular steel were (horizontal centre line of arm above rail level) - 12'6", 17'6", (possibly 21'6 - possibly for the stop arm when a lower arm distant was incorporated?') and 27'6". The short post signals weren't all that common (and there were and are some even shorter examples about) and I would think the most common was 17'6" although as far as I can find a out all the original tubular post signals with a single arm had the arm at 27'6" (they also had timber arms, not pressed and enamelled steel). 12'6" was widely used for colour light signals and numerous examples still exist. There were of course examples of the arm being mounted some way below the top of the post, no doubt to improve sighting, so the arm would not have been at the normal height. 1 hour ago, Gordon A said: In Adrian Vaughn's book Great Western Signalling the only tube diameters I can find quoted are for the early colour light signals, which is shown as 5 1/2" and 6 1/2 ". Another diagram refers to the posts as "standard posts". Anything with brackets appears to have a main post made of I girders. Gordon A There is definitely a drawing showing 5.5" diameter for a doll on a bracket signal on a semaphore signal in that book. Generally, and just about near universally, tubular steel bracket signals used tube for the main upright. But there were some very rare exceptions which used I section angle - I'm fairly sure there was one at North East Jcn in Cardiff docks and it was unusually tall for some reason. Link to post Share on other sites More sharing options...
Junctionmad Posted March 4, 2019 Author Share Posted March 4, 2019 Thanks for all these contributions does anyone have a good of of the back of the signal showing the arrangement for the spindle and lamp support bracket everything else I’ve now got good dimensions on I’m 3D printing the fittings to slide onto a suitable set of brass tubes , hence my interest in the exact type of clamp on fixture thanks dave Link to post Share on other sites More sharing options...
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