Mountain Tunnel Material

What materials will i need to construct a mountain tunnel?

I am in the process of making mine out of various foam, some 1", 2" thickness. Sorry, no pics yet but stack them, glueing between sheets, each time on each side of your track and when you reach the roof stage of your tunnel, lay one sheet over the two sides and continue upward to the desired height of your mountain. Then shape the foam with a hot wire to create your slopes. Then use plaster clothe to blend your sheet together to make the thing appear mountainous. Then I will be using Woodland Scenics tunnel portals for my openings, using joint compound to fill in around the portals to make the rocky appearance. Hope that makes sense. J1

Well, I will show you some pics of my mountain tunnel. I made mine out of 2" foam stacked and then carved/sanded down to shape.
http://community.webshots.com/photo/109373438/205281499jUbLXW this is the mountain after I have shaped it and patched it with some plaster cloth. Just remember to paint the inside of the tunnel before you put the top on it.
http://community.webshots.com/photo/109373438/205281618xbIMHg I put the tunnel portals in place and, after making sure that the foam on the inner tunnel did not stick out when the portal was in place, I supported the portal and filled the gaps with expanding insulating foam. I used a latex-based foam called DAPtex, but it dried soft. I don’t know how it will react with the insulation foam currently on the layout, but I know that Great Stuff dries harder and thus will create a more stable scenery base.
http://community.webshots.com/photo/109373438/215080325HaPeex Then, after I shaped the foam and the mountain to create a more gradual transition to the portal, I covered the insulation foam with plaster cloth, providing a better scenery base. As this photo shows, I also covered the inside of the tunnel transition with plaster cloth.
That’s the basic idea.
Reed

Bnnnboy, did you create any “trap doors” to rescue derailed equipment inside? If so, how did you do this and if not, why not? That’s the statge Im at right now and was wondering that for those who created tunnels. Thanks, J1

My tunnels are short enough that I can reach in and rescue any derailed cars. If you have longer tunnels, you might want to create some kind of liftout section.
Reed

… jamison1, after viewing bnnnboy’s pics, what you said makes ideal sense. I think i will forego the chicken wire stuff and head out for some foam. Can i get this stuff at Home Depot? Thanks, guys.

Mac

Yes, home depot sells it in 4’ x 8’ sheets

  1. Mountain
  2. Dynamite

Apply second item to first to make a hole. Repeat if necessary.

(sorry, couldn’t resist)

Making a tunnel depends on what you are using for scenery in general, and what you are doing for benchwork. You need to consider if your tunnel is long enough to require access from “inside” to deal with derailments and such. If your scenery material is wet – like plaster – you probably want to protect your tunnel before you build the mountain over the top.

In general, it seems that you should have the subroadbed or benchwork for the track in the tunnel be wide enough to support the train if it falls over for any reason.

Create some sort of reach-through so you can retrieve any derailed trains. Obviously, you need to hide this from outside the tunnel, so people don’t see your open benchwork when they look into the tunnel.

Your tunnel track may curve enough that some simple viewblocks may be sufficient for outside, while enabling you to reach what you need in an emergency.

Good luck!

… hey Jason, you had me going there for a second with the dynamite stuff… that was good. As far as access to the inside of the tunnel, i will need more ideas on building a side entrance [out of sight] or some type of removable part of the mountain to allow access.

If your tunnels are longer than a couple of feet you definitely need to provide some type of access to get to derailed equipment. ‘Lift out’ or ‘lift off’ hatches are one way of doing it. You can take a look at the following site on railimages to see how this guy is using foam and making lift out hatches. Or, at least you can once railimages is back up. Their server seems to be down at this moment. They often seem to exceed bandwidth near the end of the month.

http://www.railimages.com/gallery/johnwood

Regards

Ed

Wow Ed, thanks for the link to John Woods’ album. The pics are super-helpful.