Hello, I have my benchwork completed and have started laying out the sub-roadbed on my new layout (12x12) I have several bridges and overhead crossings to create. I am using the cookie cutter method. 1/2" plywood w/cork roadbed. What would you advise for the min. distance rail to rail at these bridge locations? Thanks in advance, Rex
First of all, what scale are you working in? Second, I assume you mean vertical clearances rather than horizontal?
Tpoic says HO, so I’m guessing HO sclae vertical distances, shoot for 4", but you can probably go as low as 3.5" depending on what your running on it.
Jay
HO, yes, Vertical. For the most part I have plenty of room to keep my grades at 2.5%. I do have one section however that is a 22" radius in a half of a figure eight.
I’d suggest you invest under $10.00 at a hobby shop for an NMRA gauge that gives you all clearances for every situation. Vertical, horizintal, station platforms, track gauging. The whole nine yrads!
Excellent suggestion, and if you were planning to run modern cars like the Athearn Genesis AutoMax or 86’ hi cubes, you’ll need even more, but with 22" radius, you will not be…
The NMRA gauge is an excellent took that is based on various clearances on tangent (straight) track. The standards and Recommended Practices are on the NMRA web site. There is also a good explanation of the clearances and the gauge as related to the prototype at::
http://www.nmra.org/standards/gauge.html
The clearance Standards are at:
S-7 Clearances
http://www.nmra.org/standards/s-7.html
S-8 track Centers
http://www.nmra.org/standards/s-8.html
This probably more than you wanted to know, but if you just read the info at the first URL, you will have a good understanding of what goes into vertical clearances.