I plan to build 2 relatively short tunnels in a series. I understand the track has to be as close to "bullet proof" as it can be to avoid having to make major repairs in the landscaping. It will be a single track section without any turnouts. I have Woodland scenic entrances. I'd like to have the interior face visible to those that would take the time to look. I live in a Philadelphia suburb and have frequented a tunnel on the NS freight line that runs through Valley Forge National park. The tunnel is the "Black Rock tunnel" and dates back to the Reading and Pennsylvania RR days. The interior is smoothed over rock from what I can see walking up to but not through it. Almost looks like it was carved out and sprayed with a concrete like material. It is arched. Any ideas on the best way to accomplish it? I could use styrofoam for the basic shape but how do I achieve the curved structure? Any ideas are welcome including references to other sources if it's too much to go into here. Thanks in advance.
Bob C.
Bob,
Just how long are your tunnels going to be? I have seen "short" tunnels that you could see from end to end easily, other "short" tunnels that were long enough or with a enough curve so you could not.
Using extruded foam, you could easily carve out a short tunnel, glue chunks together, smooth the inside and cover with Sculptamold or other product to smooth it to look like concrete. Might be able to smooth it enough so that just a good coat of paint would work. If your tunnel is longer, the center portion could just be two verticle sides and a top, a square tube.
If you can't reach through, you might want to consider a hollow mountain and just low sides to keep a derailed train from falling, but you could reach up in and retrieve the cars and locos. The mountain could be made with the same foam or a cardboard lattice with hardshell over it.
Good luck,
Richard
I use tin foil, about ten layers thick. Crinkle it up and then just curve it around a tube or something to get it round. You can make them as long as you want. I spray the inside with primer grey and it looks pretty good when you peer down the tunnel or run a video camera through on the front of a train.
With a carved foam entrance.
Don't forget to ballast the track in the tunnel or you will notice when you look inside.
Brent
"All of the world's problems are the result of the difference between how we think and how the world works."
Both great ideas. My tunnels will be no more then 18-20 inches long.
Might want to check a local plumber, he might have a piece of plastic 5-6 inch scrap piecesof drain pipe. Just split with a jig saw and cut it to fit your tunnel. I use the blue or pink foam insulation for my tunnels and use a wire brush to make it look like it was cut out of the stone. There are many ways to build tunnels. Check u tube for some ideas might find the one that fits your layout. Jim.
I know that tunnel. It runs under the Schuylkill Expressway across river from Conshohocken or Manayunk. Been a long time. The east portal is visible from the southbound lane of the expressway. Though I've never been up close to it...it was obvious that the east (south) portal is concrete coated. It's the oldest tunnel on the original Reading. As for the interior, I'm guessing they did with it the same as what was done with tunnels out here in the Sierra...shotcrete. Shotcrete as I've seen out here looks something like stucco but more course. I'll do my tunnel liners with fine speckled wall texture and my portals will be filled with plaster and carved as needed.
I grew up with the Reading and am modeling SE Pennsylvania very loosely.
Mark H
Modeling in HO...Reading and Conrail together in an alternate history.
I strongly recommend that you not have ANY track that you cannot reach. Remember Mr. Murphy and his famous law.
Dave
Lackawanna Route of the Phoebe Snow
Tunnel (typical) of LION:
The Route of the Broadway Lion The Largest Subway Layout in North Dakota.
Here there be cats. LIONS with CAMERAS
That's amazing!
I used foamcore/foam board for the base and ribs on my tunnel liners. I traced the opening on a pc of foamboard and then cut it out about 1/4" larger to allow for the strips and plaster. If you study the photos you can see how my basic construction is done. It is very simple, fast and quite good looking. I painted it all flat black and added a little gray drybursh to highlight the 'rock' inside. You can leave them loose, just put a few pushpins through the base to keep it from moving. If you need access you can remove it easily. This one is on a curve and had to be fitted into a space so it is cut off on one side.
-Bob
Life is what happens while you are making other plans!
farrellaa Bob, I used foamcore/foam board for the base and ribs on my tunnel liners. I traced the opening on a pc of foamboard and then cut it out about 1/4" larger to allow for the strips and plaster. If you study the photos you can see how my basic construction is done. It is very simple, fast and quite good looking. I painted it all flat black and added a little gray drybursh to highlight the 'rock' inside. You can leave them loose, just put a few pushpins through the base to keep it from moving. If you need access you can remove it easily. This one is on a curve and had to be fitted into a space so it is cut off on one side. -Bob
Bob C
Woodland Scenics makes a mold for casting tunnel interior walls.
http://woodlandscenics.woodlandscenics.com/show/Item/C1250/page/1
My own subway tunnels have vertical walls and a flat roof. This is a shot taken during construction:
For the textured walls, I used styrene sheet. I mixed up a soupy batch of Hydrocal and applied it to the styrene with a paint roller, the way they do textured ceilings. Then I sprayed it with gray primer and misted it with some black spray paint from a good distance to keep the spray light.
Another technique I've seen is to use a double layer of 2-inch pink foam and make a "tunnel cutter." This is a Weller soldering gun, with the tip removed and replaced with a piece of heavy (12 gauge) copper wire shaped like a tunnel. This modified "hot wire" cutter will carve a tunnel shape through the foam.
It takes an iron man to play with a toy iron horse.