Cardboard strip question?

Hello once again, I have decided to form my tunnel liner of cardboard strips and hot glue. My question is this.... What is a good safe length to make the cardboard strips in order to ensure i have enough heigth for clearance of cars? I did a test run useing 12" strips, but it wasnt enough clearance on the inside curve to allow a 69' double stack to clear both on the side and heigth. Would 14" - 16" gimme enough? Thanks!
steve:wave:
 

jasbourre

Member
I din't use cadboard for my tunnel, I made the walls out of styrofoam. Cut the back every inch or so for the curves, turned out nice. I added woaded newspaper arroud, then plaster cloth to finish.
 

MasonJar

It's not rocket surgery
Steve,

If you don't have one, get an NMRA Gauge - it can do all kinds of useful things like checking the gauge of wheels and track, and measuring clearances.

Until then, your best bet would be to experiment...! ;) :D

Andrew
 

Russ Bellinis

Active Member
I don't run any double stack cars, so I don't know how tall they are. If you are running track laid on ho scale cork roadbed, you can figur 1/2 inch for the track & roadbed. I would figure a 1/2 circle for the roof of the tunnel. To figure the length you need to form the roof, multiply 3.14 x the diameter to get th circumference of the circle that would form the roof. Divide that number by 2 to get the circumference of the 1/2 circle that forms the tunnel roof. measure the distance from the rails to the top of your double stacks and double it. Add that number to the circumference of the 1/2 circle you got previously and then add 3 inches to the total to account for the roadbed and track and 1 inch left over on each side to glue your tunnel liner cardboard strips down. That should get you close to the length you need for the tunel strips.
 

fsm1000

Member
Just measure the the tunnel entrance and add an inch on each end to allow for connecting to the layout. That should do it. :)
 
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