... - they are my attempt to represent a helix, which I am using to transfer from level to level. Many thanks in anticipation Allen Oakes Attachment: attach_1472_2025_helixtop_2012_07 _18_2022_16.box 490 posted: 18 Jul 2012 21:29 from: Martin Wynne Hi Allen, Before discussing double junctions -- are you sure your 46mm track centres spacing is sufficient clearance for your rolling stock at these radii? I just did a quick check on your plan using the default vehicle sizes in the dummy vehicle tool, and it's looking too close for comfort: 2_181616_140000000.png The usual spacing for 4mm scale at these radii would be 50mm centres. regards, Martin. posted: 18 Jul 2012 22:58 from: acoake Hi Martin, Many thanks for your very quick response. I used 46mm because I think I picked it up fom one of the many books I have read on building model tracks. However, I believe that I can increase it should it be necessary. I was going to use the tools you provide, but only after I had got something approaching a reasonable plan ...