N scale tunnel clearance

"HarryM" wrote in message news: snipped-for-privacy@news.ruraltel.net... : I am building the benchwork for an N-scale layout. Is there a standard : clearance for tunnel height? I don't want it taller than necessary, but I : want it to clear the top of tunnel portals. I am using Atlas code 80 snap : track laid on cork roadbed [not E-Z track]. I initally planned for 3 1/2" : clearance, but that looks like it may be taller than I need. harrym : Harry, Here's the NMRA standard on clearances; should have the answer to your question:

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=3D>> -- =3D>> 73 de KT=D8T =3D>> Bob Schwartz =3D>> Modeling Waseca, MN in the 50s =3D>>

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=3D>Thanks. Looks like 2 1/2" would be plenty of clearance, since the s= tandard =3D>is 1 21/32" from the top of the rail. harrym

"Standard" prototype tunnel clearance is 22ft above railhead; the NMRA standard is based on this. But tunnel sizes have varied some over time a= nd from road to road. In the last decade or two, a lot of tunnels were rebu= ilt to allow for higher cars and double-stack trains (by lowering the railbe= d). Clearance is around 25-26ft and sometimes more. Make a a few tunnel mout= hs out of boxboard, and set them over a train, and see which one looks best= . If your 2.5" dimension is from the suboadbed, it will be about right. But i= t's way too high measured from the railhead (2.5" --> 33ft in N!) You are modelling the 50s after all. :-)

HTH&HF

Wolf Kirchmeir ................................. If you didn't want to go to Chicago, why did you get on this train? (Garrison Keillor)