GWR_Modeller

Hi, The GWSG site has pages of two 1938/1939 notices about specials from Weymouth Quay to transport Jersey new potatoes and French and Cornish brocolli. The main points I took from these notice are: - the special trains were Class c*, Class C and class D, where * is the funny spoked wheel symbol used to indicate no foreign grease or hair filled axle boxes. - the notice specifically states pages 172, 173 and 174 of the general appendix are to be observed. - it specifies how variuos trains are to be marshalled into vac and non vac parts for different destinations including Cardiff, Crewe London, all the big hubs. - it mentions that trains with ten wagons less than the standard load can travel faster but not more than 45 mph. - and intriguingly mentions wagons joining a meat train from the SW to Acton at Westbury. It says if the wagon numbers on the train now exceeds 35 it must proceed as a partly fitted vacuum implying that it may have been fully fitted before hand. The two lamp positions you mention in BR days are i) C and ii) D which are respectively i) "....composed entirely of vehicles conforming to coaching stock requirements" or "express freight..... piped fitted throughout with automatic brake operative on not less than half...." and ii) "express freight ....... partly fitted with automatic break operative on not less than a third.......".

Hi, Can you see the lamp position and type of vans please, also date, is it post or pre war? Paul

Just quickly looked through the preserved wagons list for AA21 preserved vans. Of the sixteen AA21s I found I could see nine with screw couplings on the photo and could not identify the others, ie none with identifiable three link/instanter. Of the similar number of non AA21 vans with similar build dates about half had screw couplings and half instanter/three link and about a quarter not identifiable. Obvious caveats -limited sample, 70 years of rebuilds and confirmation bias etc.

GWR Goods Wagons (Atkins, Beard and Tourret) and Gwr org both report screw couplings were used on AA21 (batch of 100) and one of them specifically states screw couplings were used on all fitted brake vans. My understanding is screw couplings and long buffers always go hand in hand. And I have learned recently when joining screw coupling fitted vehicles to others with instanter or three links, ie with shorter buffers, the screw coupling was not to be used. I think it is an interesting hypothesis that the brake vans and goods vans built with screw couplings in in 1938/9 and which were government funded were intended for continental work. Any evidence for that?

Well that is what puzzled me as well. Page 173 of the 1936 General Appendix to the Rulebook refers to C class trains and describes "the maximum and minimum proportions of vacuum brake-fitted vehicles required to be connected to the train engine, if the train is to run at its booked speed except in cases where a different proportion is specially authorised........" Basically it is at least a third and less than half eg for a forty wagon train the min is 13 and the max 20. But it also says in short trains of upto 16 wagons all can be vacuum braked. This does not fit my previous understanding of fully fitted express freights which I expected to be longer. As far as I can tell in trying to understand the purpose of that and other restrictions the problem in a loose coupled train is if you apply the brakes and slow the front of the train too quickly then the rearmost wagons close up without slowing and then impact the wagons in front at an excessive speed difference. Alot of the rules seems to be about preventing that. So there is a sweet spot between adding more braking power to the train as a whole while not causing the problem described above. And the GWR decided that was a third to a half fitted. I think that can be inferred? Presumably in a close coupled fully fitted train all the wagons slow at the same time and the problem does not occurs. So my question was about identifying whether there were fully fitted ordinary goods trains or not and how they were identified in timetables since C class is already the fastest class of goods? You are correct in 1939 for the first time GWR built a batch of fitted, as opposed to piped, brake vans with screw couplings and at about same time completed over a thousand fitted ordinary goods vans with screw couplings. Presumably for fully fitted ordinary goods trains. How were they identified in timetables?

Hi, Obviously passenger trains and passenger class trains like parcel, mail and newspaper trains were fully vacuum braked throughout. But what about express goods trains. Did the GWR run fully fitted goods trains? In late 1930s head code C freights had no less than a third and, I believe, no more than half of the wagons vacuum braked. Headcode D trains had a minimum of four vacuum braked vehicles at the front and for longer trains it increased. Was there another category which was fully fitted? Paul

Just to be certain I understand correctly.... Coaches and wagons all had couplings both ends. So to connect a pair of railway vehicles together only one of the couplings between them had to be used and the other was surplus at that specific time? In the case where one vehicle had a screw coupling/longer buffers and the other had a three link/instanter then only the latter could be used? Either that or the emergency screw coupling? In that case the 1000 plus 12t goods vans manufactured with screw couplings/longer buffers (see first post) would have to be managed carefully to marshal them into trains altogether because if not then mixing them into a vacuum train with the other vans having three link/instanter fittings would negate any advantage of the diferent fittings. Is that a reasonable supposition? How would that work if they left GWR area? Do you think they were NCU?

Goods vans wouldn't run in a passenger train would they?

There do not seem to have been earlier large batches of ordinary goods van with these fittings. Meat vans, cattle wagons, the few Mink Fs but others? So over a thousand 12t vans in a short period seems to be a specific decision rather than routine addition.

Vacuum freights had been running for 30 years plus with fitted stock and instanter couplings. So did the fitted goods vans with screw couplings, and long buffers, in large numbers, serve a new class of train or type of traffic?

Yes those as well but for what purpose?

Hi, I am reading a series of articles in GWRJ about goods vans. One part of the series mentions the V23 diagram of 12t vacuum fitted Van's built between 1934 and 1941 There were about 4000 of these. In 1938 and 1939 1197 were, the article records, completed with screw couplings rather than normal goods van fittings. At the same time the V24 diagram of unfitted vans was being built. So there are three concurrent van types being built ie unfitted, fitted with 3 link couplings and fitted with screw couplings. How did the use of the screw coupling fitted vans differ from the other vacuum fitted goods vans? Regards, Paul

I model in N and I found the commercial shets ones I bought were too thick and difficult to fold to suit me and so I made a few of my own from Rizla papers, plain not liquorice, and tin foil. Once cut to size and folded over a shaped load I dropped runny super glue on the paper to set it.

Yes that's the one.

Hi, A while ago I made some notes for modelling a gwr goods train, one of those notes was that ca. 1939 GW wagon sheets were all a single standard size ie 14'4" by 21' and the markings were much simplified with GWR and sheet number twice each in white facing the shorter sides only and the reproofing date in red four times facing the long edges. I cannot remember exactly which books I noted it from but suspect it was GWWay later edition or perhaps an article in GWRJ. Will see if I can find the ref this evening.

It can certainly be pollution causing stone to discolour even if it was not staining by black soot deposits. In the atmosphere as a result of coal, petrol and diesel burning there is a concentration of sulphides, sulphites, sulphates, nitrous oxides, nitrites, nitrates, often in form of acids, lead compounds, carbon monoxide and loads of other stuff which would not be there in those quantities except as a result of burning fossil fuels. Limestones, containing magnesium and calcium carbonate compounds, react with some pollutants and discolour. In addition the presence of some pollutants or their decomposition products on stone surfaces provides nutrition for microbial growth also causing discolouration. Blackening may be a 'natural' process but it was certainly speeded up by pollution. On the plus side I did hear that it was possible to grow very good roses downwind of coal burning power stations because the activity of the pollutants reduced black spot desease so not all bad.

I suppose it would be H2s(g)+pbco3 = pbs+h2o+ co2(g) in simple terms. I do not know that reveals any more than the original sentence did. It has been a very long time since I studied chemistry and I am sure paint pigment was not simple lead carbonate alone and the reactions are more varied and complicated than that.

Hydrogen sulphide reacts with lead carbonate to create lead sulphide, which is grey. In general terms Hydrogen sulphide is reactive rather than not.

Hi, I am an n gauge modeller and in my experience I found the packageing used by Dapol, Farish and Peco on their n gauge locos, coaches and wagons to be more than adequate. Dapol coaches in this scale are very tightly packed and care is required to remove them from the foam surround. In some cases the packageing seems excessively robust and perhaps contributes too much to the cost of cheaper models. On the other hand I do see that for some customers models will have to travel several thousand miles in various postal systems so the manufacturers have to take that into account.

Okay a local variation to GWR standard codes. Thanks.

I have just come across three photographs of engines with a single central lamp on the buffer beam. This was in 'Great Western Railway in the 1930s'. The problem is that is the light engine code 'G' and the three trains consisted of 10 passenger coaches, a B set and an unknown number of carriages. So can anybody suggest what might be going on?

May I refer you to Bob Esserys' softback books "Freight train operation" pgs 62 and 63 and "Passenger Train Operation" pg 36. Although these are not primary sources they indicate posible explanations for both the "Class A" reference by the first post and the maltese cross by stationmaster. Class A in this context I believe is not a reference to the headcodes but to a type of partially vacuum fitted freight, Class B being a vacuum fitted train with less fitted wagons. These terms appear on the older MR headcodes list not the later BR one and so are perhaps historical terminology carrried over or reference to another source perhaps the rulebook? In a GWR timetable the maltese cross would an "Accelerated E" freight. Caveat - the poster refers to the Midland Region and BR period whereas my limited knowledge is mostly GWR 1930s.

See this site. In the context you refer to seems Class A and Class B refer to types of freight train and speed rather than loco headcodes. http://britishrailways.tripod.com/headlamp.html

Great Britain?

Hi, Painting Instructions for signal boxes 1907 includes colours for level crossing lamps black. Found it in an appendix of GWR Signalling Practice GWSG D Smith. Also found two colour photos dated early 1960s in Runpast and Ian Allan books of ex GWR branchlines with black lsmps on crossing gates. Some photos on internet show red but I think generally later and more modern setting. So my provisional conclusion is GWR used black crossing gate lamps ie same as signal lamps (thats me sorted for 1930s period) but later on they might get painted red or replaced or not. Oh and the red target in both those photos facing only the rail not the road. Another photo had target facing road not rail. Dont know logic of that and will have to reread posts above to try and figure out.