RMweb Gold TheSignalEngineer Posted November 29, 2017 RMweb Gold Share Posted November 29, 2017 The circle to the left is the lead-off timber outside the signal box. I will look closer tonight at where the compensation would probably be. Do you have any large scale drawing of the area? An overhead track plan of your layout would probably suffice. Link to post Share on other sites More sharing options...
Lecorbusier Posted November 29, 2017 Author Share Posted November 29, 2017 The best I have at the moment is this Link to post Share on other sites More sharing options...
RMweb Gold TheSignalEngineer Posted November 29, 2017 RMweb Gold Share Posted November 29, 2017 (edited) The best I have at the moment is this Monsal Dale two chain plan -detail.jpg Thanks, I will print off later and mark on the cranks for 6 and 7. Edited November 29, 2017 by TheSignalEngineer Link to post Share on other sites More sharing options...
RMweb Gold TheSignalEngineer Posted November 29, 2017 RMweb Gold Share Posted November 29, 2017 I've not worked out any distances but I think the rodding would have looked something like the schematic I've added to the plan. It's only a best guess based on what I've seen so far, but would tie in with the pictures. The object under the platform edge would be where I would expect to find the compensator for the far end of the crossover and the drive crank for the slip. Link to post Share on other sites More sharing options...
Lecorbusier Posted November 29, 2017 Author Share Posted November 29, 2017 The best I have at the moment is this Monsal Dale two chain plan -detail.jpg Thanks very much for this ... it is very kind of you and much appreciated. Regards Tim Link to post Share on other sites More sharing options...
Lecorbusier Posted December 1, 2017 Author Share Posted December 1, 2017 I've not worked out any distances but I think the rodding would have looked something like the schematic I've added to the plan. monsal_0001.jpg It's only a best guess based on what I've seen so far, but would tie in with the pictures. The object under the platform edge would be where I would expect to find the compensator for the far end of the crossover and the drive crank for the slip. I have one question regarding the compensators in your layout. If the actuation of crank 6A is via a lug and bar affixed to the main rodding run which is continuous, how does the compensation work to ensure that there are no expansion issues effecting the crank at the lug? Link to post Share on other sites More sharing options...
RMweb Gold TheSignalEngineer Posted December 1, 2017 RMweb Gold Share Posted December 1, 2017 I have one question regarding the compensators in your layout. If the actuation of crank 6A is via a lug and bar affixed to the main rodding run which is continuous, how does the compensation work to ensure that there are no expansion issues effecting the crank at the lug? If you look at the schematic at the bottom of post #28, the first thing you do is work out the compensation from the box to the points worked off the drop lug. Because you take into account the distance from the adjusting crank to the stretcher bar connection pin the main rod will actually be compensated to the same distance past the crank, shown as 'N' for Null Point in the diagram. You then work out the compensation from 'N' to the second points. Link to post Share on other sites More sharing options...
Lecorbusier Posted December 1, 2017 Author Share Posted December 1, 2017 If you look at the schematic at the bottom of post #28, the first thing you do is work out the compensation from the box to the points worked off the drop lug. Because you take into account the distance from the adjusting crank to the stretcher bar connection pin the main rod will actually be compensated to the same distance past the crank, shown as 'N' for Null Point in the diagram. You then work out the compensation from 'N' to the second points. It was more the Physics I was trying to get my head around (not my strong point) .... I assumed that your workings and diagram were correct. I understood the principle of compensation to be that effectively the rod is fixed at the actuation crank end but expansion is free too take place at the compensator? Thus if the rodding lengths are equalised then the expansion is neutralised by the compensator without changing the effective rod length and so mucking up the crank geometry. What I couldn't get my head around was how this played when the fixed point is a distance along the crank with a compensator at each end ... I suspect I am being thick! Does the lug position remain static and the ends of the rodding expand away from the lug? Link to post Share on other sites More sharing options...
Lecorbusier Posted December 1, 2017 Author Share Posted December 1, 2017 (edited) Thought I would upload some further images I have unearthed relating to midland rodding in case they might be of use to others. Edited December 1, 2017 by Lecorbusier 1 Link to post Share on other sites More sharing options...
Grovenor Posted December 1, 2017 Share Posted December 1, 2017 What I couldn't get my head around was how this played when the fixed point is a distance along the crank with a compensator at each end ... I suspect I am being thick! Does the lug position remain static and the ends of the rodding expand away from the lug? Nearly, but its not the position of the drop rod from the main run that needs to be static but the final connection onto the drive stretcher. So the 6A compensator has to compensate for all the rodding from box to the final connection, ie box to lead out crank, lead out crank to comp, comp to 6A drive crank and drive crank across the track to the points. For this length you need the length of rodding in 'push' to equal that in 'pull'. The arrows signal Engineer put on his diagram are to show which is which as direction may change at cranks as well as at compensators. This means that the position along the main rod where the rod does not move, the neutral point, is not actually at the drop rod position but some distance away to allow for the effect of the rods across the track. Regards Link to post Share on other sites More sharing options...
Lecorbusier Posted December 1, 2017 Author Share Posted December 1, 2017 Nearly, but its not the position of the drop rod from the main run that needs to be static but the final connection onto the drive stretcher. So the 6A compensator has to compensate for all the rodding from box to the final connection, ie box to lead out crank, lead out crank to comp, comp to 6A drive crank and drive crank across the track to the points. For this length you need the length of rodding in 'push' to equal that in 'pull'. The arrows signal Engineer put on his diagram are to show which is which as direction may change at cranks as well as at compensators. This means that the position along the main rod where the rod does not move, the neutral point, is not actually at the drop rod position but some distance away to allow for the effect of the rods across the track. Regards So .... does that mean that any displacement due to expansion at the lug position which will shift the crank position will be compensated for by an equal expansion in the opposite direction from the rods across the track? Link to post Share on other sites More sharing options...
Grovenor Posted December 2, 2017 Share Posted December 2, 2017 Yes. Regards Link to post Share on other sites More sharing options...
technohand Posted March 7, 2018 Share Posted March 7, 2018 Thank you all for the information in this post. As a fellow Midland Railway modeller I have had great difficulty getting information on the way they did things especially regarding track work. This post has been of tremendous help. Thank you all Link to post Share on other sites More sharing options...
technohand Posted March 15, 2018 Share Posted March 15, 2018 Further to my post I have taken the liberty of copying some of the pictures to The Midland Railway Forum and refered to these articles as a valuable source of information. Thanks Again Tony Link to post Share on other sites More sharing options...
Lecorbusier Posted March 15, 2018 Author Share Posted March 15, 2018 (edited) Further to my post I have taken the liberty of copying some of the pictures to The Midland Railway Forum and refered to these articles as a valuable source of information. Thanks Again Tony Could you post the link to the Midland Railway Forum ... I am not familiar with it. The later images posted by me are part copies (details) from NRM originals... so publication copywrite would I think apply. Edited March 15, 2018 by Lecorbusier Link to post Share on other sites More sharing options...
technohand Posted March 15, 2018 Share Posted March 15, 2018 I started the Midland Railway Company Forum as there was little information on RMWeb on this company. There were some posts mostly about rolling stock as you will see if you go on it. I have copied the pictures from this site as I am sure other modellers are just as interested in the Midland way. If I have inadvertently breached copy right then I apologise. I thought that as they are effectively in the public domain no one could be offended. It is not my intention to make money out of the actions purely to add to the knowledge base. Regards Tony Link to post Share on other sites More sharing options...
Lecorbusier Posted March 15, 2018 Author Share Posted March 15, 2018 I started the Midland Railway Company Forum as there was little information on RMWeb on this company. There were some posts mostly about rolling stock as you will see if you go on it. I have copied the pictures from this site as I am sure other modellers are just as interested in the Midland way. If I have inadvertently breached copy right then I apologise. I thought that as they are effectively in the public domain no one could be offended. It is not my intention to make money out of the actions purely to add to the knowledge base. Regards Tony Tony, Sorry, I wasn't clear there. My understanding is there is no issue for non commercial usage as the images are simply cropped and enlarged details and as such unrecognisable. However, the originals are not in my ownership and have only been shared for non commercial/private academic usage and this should perhaps be made clear. Link to post Share on other sites More sharing options...
technohand Posted March 15, 2018 Share Posted March 15, 2018 Will do Tony Link to post Share on other sites More sharing options...
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