How do you guys secure your track inside a tunnel? I have nailed it to the cork roadbed, but I’m not sure if that is enough. My tunnel will be about 4 feet long, so I will be able to reach into it from either end in case of a derail. But are the nails enough? Maybe a shot of caulking is better and re-nail it down?
I have two tunnels - each over 12’ long. The Atlas code100 flex is attached to Homabed with standard 1/2’ track nails every 6"(I drill extra holes). The rail joiners on the curves are soldered, but feeders every 3’ are soldered to the rail. Using latex caulk will not hurt.
Jim
I always lay the track before putting any scenery above it. Then I run the trains for months to make sure no problems develop. If you can’t reach the track to fasten it down, you can’t reach it to fix problems which might occur.
Think about opening up that scenery to provide access. The center of your tunnel is 2 feet from either end. Take a ruler and measure 2 feet from the palm of your hand, because you can’t grab with your fingertips. On me, the top of the tape measure comes up almost to my shoulder. And I’m sure I couldn’t even get my elbow through the tunnel portals.
It somewhat depends if the track is straight or curved, but if the nails aren’t spaced too far apart they should be fine. If you want to be as sure as possible then you can take up the track and fasten it down with caulk and nails. It may sound like over kill, but better to take care of any problems now then to wait until you have the track covered by scenery.
I also suggest that you make the scenery over the tunnel (mountain? hill?) either removable, or provide access to the track from behind. I had a relatively short (14") tunnel on an old layout of mine that had no access other than the tunnel portals. Even though I had tested the track for 6+ months before applying scenery I always seemed to have a derailment in the tunnel and trying to retrieve N scale cars out through the portals was extremely frustrating (I can’t imagine what it would be like dealing with a tunnel 4 ft in length).
Some simple ballasting of the track will also keep it in position.
So far, every millimeter of track I have laid is meant to be hidden, so I guess it fits the definition of ‘tunnel track.’ It takes several forms:
-
Raw rail spiked to pine board (look ma, no ties.) Spikes every two inches, both sides of both rails. Found at the track bumper ends of back-in staging yards. Readily accessible, either through the fascia (removable panels) or by lifting off a mountain (of rigid foam) or part thereof.
-
Flex track laid on fan-fold underlayment (thin rigid foam) with latex caulk, track nails through every hole provided by the manufacturer. Some of it is all but impossible to access.
-
Hand-assembled specialwork on wood ties, ties anchored with caulk, two spikes in every tie for every rail. The more complex puzzle palaces can be removed from the layout for maintenance, and can be accessed like the rest of hidden staging if problem-correcting is necessary.
I have been operating on the oldest parts of the Netherworld for over two years now, running a variety of trains of every class almost every day, and can honestly say that the trackwork has proven to be utterly dependable. Still, I suspect that if I hadn’t provided for adequate access, Murphy would be having a field day.
Chuck (Modeling Central Japan in September, 1964 - with LOTS of track in tunnels)