RMweb Gold The Stationmaster Posted March 31, 2012 RMweb Gold Share Posted March 31, 2012 Looking at the working timetable between Derby and Chesterfield the timings are different between the two Classes of train so I would reckon that a Class 7 train was timed so that it contained wagons that had a maximum speed of at least 45 m.p.h. whereas the Class 8 train was timed so that it contained wagons that had a maximum speed of at least 35 m.p.h. That is possible, indeed likely, but beware that there were considerable inconsistencies in the timing of freights on the LMR although 'later introductions' such as company trains with modern wagons and Freightliners seem to have been much better. The difference could also be down to different (planned) levels of loading, i.e. heavier trains were timed slower than lighter ones although the LM weren't - in my experience - that sophisticated with a lot of their freight timing. Are there any other notes in the column headings? Link to post Share on other sites More sharing options...
Flood Posted March 31, 2012 Author Share Posted March 31, 2012 Are there any other notes in the column headings? Not in the column headings, just the note at the front stating "Documentation for other Freight trains in Classes 6, 7, 8 and 9 will be included in the existing Freight trains Loads Book". In reply to Brian I agree that as the other drawings I have came from the Rolling Stock Library at the Tech Centre then not all the information changes may be present. The specific Loads Book may well have stated a blanket speed restriction of 35 m.p.h. on 9 ft wheelbase wagons. Link to post Share on other sites More sharing options...
RMweb Gold The Stationmaster Posted March 31, 2012 RMweb Gold Share Posted March 31, 2012 Not in the column headings, just the note at the front stating "Documentation for other Freight trains in Classes 6, 7, 8 and 9 will be included in the existing Freight trains Loads Book". In reply to Brian I agree that as the other drawings I have came from the Rolling Stock Library at the Tech Centre then not all the information changes may be present. The specific Loads Book may well have stated a blanket speed restriction of 35 m.p.h. on 9 ft wheelbase wagons. As far as the latter is concerned the 1975 Western Region Loads Book (which I even kept fully amended ) shows nothing at all about individual wagon type speeds because they would be shown in the WMRS (Working manual For Rail Staff) and on the wagon data panels, plus they would be in TOPS (although coverage was incomplete at that time of course). The only specific speed restrictions shown are for Class 9 trains (max 25 mph) and there are some notes in regarding the application and effect of using different columns in the Brake Force tables (e.g C instead of B). As stated previously there were differences in the way the Regions published their Loads Books but unlees the LM were unusual the only information it would have contained would be Loads by loco class for each route section, and which Brake Force column applied (although probably not in the case of every train) with particular classes of loco etc. Link to post Share on other sites More sharing options...
Flood Posted March 31, 2012 Author Share Posted March 31, 2012 Thanks Mike. I would say that for operating model railway purposes I could get away with running not fully fitted freights at a scale speed of 45 m.p.h. unless they have 9 ft wheelbase or other specific vehicles types, in which case it would be a scale speed of 35 m.p.h. Link to post Share on other sites More sharing options...
RMweb Gold The Stationmaster Posted March 31, 2012 RMweb Gold Share Posted March 31, 2012 I would say that for operating model railway purposes I could get away with running not fully fitted freights at a scale speed of 45 m.p.h. unless they have 9 ft wheelbase or other specific vehicles types, in which case it would be a scale speed of 35 m.p.h. I think so. Mind you in model form the speed difference won't show much anyway I suspect - at 1:1 scale the difference between 35mph and 45 mph over a quarter of a mile is 5.7 seconds. I'm not at all sure how time might be scaled (??) but scaling the distance to 4mm scale means a difference of 5.7 seconds over c.17ft 6ins but it would be more noticeable over half that distance for2mm scale of course. Link to post Share on other sites More sharing options...
Flood Posted March 31, 2012 Author Share Posted March 31, 2012 That's ok, the trains will be running on the club layout of Duffield which is 36 ft long. You are quite correct that only the distance needs to be scaled (I'm not going to go into this more as it has been done to death on too many forums already) so to complete the front length of our layout a 35 m.p.h. freight will take approx 53 seconds and a 45 m.p.h. freight will take approx 41 seconds, quite a difference. Link to post Share on other sites More sharing options...
Edwin_m Posted March 31, 2012 Share Posted March 31, 2012 I believe some short wheelbase wagon types had their speeds reduced back in the 60s after a spate of unexplained derailments, of which the accident that wrote off DP2 was one. Link to post Share on other sites More sharing options...
Fat Controller Posted March 31, 2012 Share Posted March 31, 2012 I believe some short wheelbase wagon types had their speeds reduced back in the 60s after a spate of unexplained derailments, of which the accident that wrote off DP2 was one. The incident that wrote off DP2 involved Cemflo tanks, which had a 15' wheelbase. There were a spate of plain-line derailments involving fast fitted freights with 10' wb wagons, however, which meant that these wagons were henceforth restricted to 45 mph. The majority of these derailments took place on the recently-introduced continuously-welded rail, possibly due to a combination of cyclic top (a lot of the relaying work had simply replaced the old track with new, without dealing with problems in the sub-base below the ballast) and poorly performing bearings and suspension. One day, I must dig up my remaining Modern Railways from the period, and re-read the HMRI reports in the light of what I have learned in the subsequent forty or so years; there seemed to be at least one plain-line derailment in every issue at the end of the 1960s. Link to post Share on other sites More sharing options...
Edwin_m Posted March 31, 2012 Share Posted March 31, 2012 No need to do that, the invaluable Railways Archive has the original reports and there's even a search option to pull up all those relating to SWB wagon problems. Link to post Share on other sites More sharing options...
Flood Posted April 8, 2012 Author Share Posted April 8, 2012 After another week of investigation I now have a copy of the 1975 LMR White pages which not only states that the timings for Class 7 freights were based on 45 mph and those for Class 8 were at 35 mph but also contains a list of exceptions from a maximum speed of 45mph if the speed for a vehicle was not known (Section C1/9). Keefer has very kindly checked his 1982 copy and this information (revised to section B2/7) also stated 16.5 tonne mineral wagons. As these were not included in the 1975 list the restriction was either brought in between 1975 and 1982 (probably after 1978 going by Rivercider's info in post#21) or was brought in with the 1982 revision. So to summarise: Class 7 freights were timed to run at 45 mph (given gradient conditions etc) but could run higher up to the maximum speed of the slowest wagons. Class 8 freights were timed to run at 35 mph but could run higher up to the maximum speed of the slowest wagons. Class 9 freights could not exceed 25 mph. Iron Ore, Ironstone and Sand hoppers (and Anhydrite wagons) with a wheelbase of 10ft or less had a maximum speed of 35 mph. All 16t mineral wagons were also restricted to 35 mph in the 1982 copy. Cemflo and 56t Armour plate wagons had a maximum speed of 35 mph loaded and 45 mph empty. The 1982 copy specifically lists APCM hopper wagons (APCM 8301-8490) and APCM presflo (APCM 8500-8594) as opposed to just stating Cemflo. 42.5 t Trestle, 40.5t Flatrol, 40.5t Trestrol, 20.5t Weltrol and 25.5t Weltrol wagons had a maximum speed of 40 mph loaded and 45 mph empty. Link to post Share on other sites More sharing options...
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