In the November 2012 issue, Jim Hediger mentions laying the flex track with the moveable rail to the inside of the curve to keep the ties parallel to the rail. I agree with the esthetics of the argument but I have found this method tends to kick the rail to the inside thus reducing the track gauge. On short curves this would be less of a problem but my experience when laying continuous curves, as in a helix, is to lay the moveable rail to the outside. When laying a helix, I start at the lower end and as I work my way up the helix I slide the next piece into the fastened sections ties and solder the rails wherever they end. I never allow joints to be side by side. This prevents any kinks at the joints and produces a very smooth transition from one rail to the next just like the prototype. My N-scale helix is twin-tracked, 17.5" & 19" radius and is code 80 only through the non-visible portions of the helix. The balance of the layout is all code 55.
I have found rail-nippers to be the easiest to cut rail to exact locations and I clean the end with a Dremel disc and a small file before installing the rail joiners.
I haven’t found any difference really with large curves whether the moveable section is inside or outside since the ties should stay perpendicular to the rail at the tangent point regardless.
I agree and think it is a practical must to have offset soldered joints on curves. I like to solder them with the sections of track as straight as possible, maybe up to 3 sections of 36" flextrack and then lay them gently using a radius gage to avoid kinks and inconsistent radii.
Richard
I have bent Atlas 16.5mm gauge flex track to radii less than 12 inches (part of a test spiral) and NEVER found the gauge to be less than NMRA standard as measured with the flat gauge.
My curves are laid with the loose rail to the inside. That way the excess rail length (beyond the end of the tie strip) appears on the inside, and can be slipped into the tie strip of the next length to offset the joints. The flying end isn’t cut short until the track returns to true tangency, past the end of the spiral easement. (The odd end is worked into hand-laid specialwork.)
As the above implies, I stagger rail joints on curves. I also pre-bend my flex track, using pliers if necessary, until the track lays on the desired alignment without stress. The joints aren’t soldered, but I do solder jumpers around them.
Chuck (Modeling Central Japan in September, 1964)
I have considered this ‘urban myth’ of changing gauge and have found it to be a bunch of hooey, as Chuck clearly has. While you could argue that there is a measurable change in the gauge one way or the other, the difference couldn’t possibly exceed the engineered distance between the channels afforded by the plastic spike head details all along the lengths of flex. IOW, we’re talking maybe a very tiny portion of a single millimeter. Looking soberly at the slop allowed by NMRA standards in both compliant turnouts and in their negotiating wheelsets, the difference is ignorable.
Crandell