jukebox Posted February 18, 2012 Share Posted February 18, 2012 I'm currently track planning, and in trying to maximise the headroom between lower level storage yards and the scenic area, I'm thinking of locating the turnouts that fan out the arrival tracks actually on the downward slope to the yard. Has anyone else deliberately positioned turnouts on a constant slope, rather than on the level?** If I did go down this route (pun intended!) the slope from the start of the ramp to the bottom would be 5% downhill to the yard, 3% up hill back to planet earth, but constant from top to bottom, so there would be no vertical curves near the actual turnouts. FWIW I'm thinking of using Peco SL-E187's, as these turnouts are not in view, and only RTR locos would need to run on them. **Disclaimer: Yes, I know this is considered a "NO! NO!" in many texts. But rather than "it's not recommended", I 'd really like to hear from people who have tried it and had grief, or made it work. Link to post Share on other sites More sharing options...
RMweb Premium Kris Posted February 18, 2012 RMweb Premium Share Posted February 18, 2012 I've done it is the past. Not ideal but with care it was possible to get it to work. Link to post Share on other sites More sharing options...
Katier Posted February 18, 2012 Share Posted February 18, 2012 I would hazard a guess the most important thing is to have a good straight run either side of the points before any transitions in any directions. Link to post Share on other sites More sharing options...
RMweb Premium Kris Posted February 18, 2012 RMweb Premium Share Posted February 18, 2012 I would hazard a guess the most important thing is to have a good straight run either side of the points before any transitions in any directions. Where I had points on a gradient the lead in and out track was curved (I didn't make things easy for myself). It was very important to make sure that the track joint between the point and the led in / out track needed to be perfect and adding a cant into the point caused all sorts of issues. Link to post Share on other sites More sharing options...
Poor Old Bruce Posted February 18, 2012 Share Posted February 18, 2012 I would hazard a guess the most important thing is to have a good straight run either side of the points before any transitions in any directions. Agreed. If the points and their immediate environs are flat i.e. no change of gradient, then there shouldn't be any problem. Link to post Share on other sites More sharing options...
RMweb Gold Budgie Posted February 18, 2012 RMweb Gold Share Posted February 18, 2012 It seems Network Rail doesn't have problems with turnouts on a constant slope. Take a look at http://www.bescot.plus.com/trains/73201_Lewisham2381 and you will see a crossover on the 1 in 80-something line past the double-track scissors crossover. Link to post Share on other sites More sharing options...
HLT 0109 Posted February 18, 2012 Share Posted February 18, 2012 If you put a point into a gradient, there is bound to be a cant on the curved part (assuming no opposite cant on the straight) and 5% (1:20) is quite steep so I would expect difficulties. I have a point at the top of my 1:15 gradient so the the curve side starts the gradient whilst the straight side remains level. I have therefore both a cant and a twist in the point. I did have problems but managed eventually to get it to work 100%. I couldn't use any calculations to get it right - just trial and error - and you may have to try temporary fixing with packing to create a slight twist. It will help if you do not use a small radius point - mine is a Hornby express point which gives a gentler curve. Good luck! Harold. Link to post Share on other sites More sharing options...
RMweb Gold Donw Posted February 18, 2012 RMweb Gold Share Posted February 18, 2012 I built one in 0 using C+L components where the main was curved on a constant gradient quite gentle slope and the diverging route was straighter and went in the opposite slope from the crossing. At that time I didn't know any better so it worked ok. Don Link to post Share on other sites More sharing options...
jukebox Posted February 20, 2012 Author Share Posted February 20, 2012 Thanks everyone for the cross-section of responses. The comments regarding transitions, and maintaining a smooth constant grade, all ring very sound, as does your warning about negative cant, Harold. I would expect this is why I may need to use careful adjustment and localised shimming to neutralise any ill effects of wayward centrifugal forces if I am not seeing solid reliability at first. I think the logical approach will be to experiment by laying the steeper arrival gradient fan first, with it's facing turnouts, and testing that across a range of rolling stock and locomotives both propelled and hauled - after all, if I can't get trains down that slope to begin with, the gentler departure slope will be even less severe if I have to alter the depth the storage is set at. Link to post Share on other sites More sharing options...
RMweb Premium Gwiwer Posted February 20, 2012 RMweb Premium Share Posted February 20, 2012 I not only have a full double-track main-line junction on a gradient but it forms part of a larger complex of junctions with a main line descending from the hills meeting a branch rising from the yard and an assumed jetty before all intersect and merge onto level track. It works well with the only issues having been the placement of point motors on inclined points (they don't like it so I went for surface motors which are on the same plane as the track) and the need to ensure nothing grounds out over a change of gradient (among the 00 stock it doesn't but one Australian HO loco which seldom gets used anyway is banned from descending the branch). The greatest challenge was trying to get all the tracks smooth and evenly graded without anything appearing to "step" over a change in gradient. A lot of trial and error was necessary before it looked right. Even then if the diamond were left on a gradient for one route it would offer adverse cant for the opposite route so the two effects have had to be carefully minimised while a small element of both remains. It works and it has worked successfully for some years now. Operators need to be aware of the gradients and manage the trains accordingly as a long one descending the main line may have the couplers bunched. Snatching as the train runs out onto level track has a potential to cause parting of the vehicles but in practice is a very rare occurrence. A train departing the viewing area to the fiddle yards also has a speed restriction in order to safely negotiate the downhill turnout, diamond and curve beyond. Link to post Share on other sites More sharing options...
mobi323 Posted February 20, 2012 Share Posted February 20, 2012 Where I had points on a gradient the lead in and out track was curved (I didn't make things easy for myself). It was very important to make sure that the track joint between the point and the led in / out track needed to be perfect and adding a cant into the point caused all sorts of issues. I tried this (curved point on an incline) on my layout but had to give up. Too many issues. Also you may get it to work for one engine but another would be hopeless. I am 67yo an life is too short to try to sort out these problems. LOL. Link to post Share on other sites More sharing options...
Kenton Posted February 20, 2012 Share Posted February 20, 2012 I have only had success with points on gradient in NG OO9 where the tolerances are much wider. I wouldn't dream of trying in any of the fine scales. Though in reality it probably depends more on the gradient being used than the scale+gauge. Link to post Share on other sites More sharing options...
Grovenor Posted February 20, 2012 Share Posted February 20, 2012 The junction in this pic is on a grade of around 1:25, works just fine, built on the level and the whole board tilted. Keith Link to post Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.