Tunnels

[mightymax]

Have got to a point on my project where I need to build a short tunnel, I've got lots of slate and stone, but is there a good way to build a tunnel ? . If anyone has pictures of theirs I'd love to see them.thanks.

[philipy]

Have got to a point on my project where I need to build a short tunnel, I've got lots of slat and stone, but is there a good way to build a tunnel ? . If anyone has pictures of theirs I'd love to see them.thanks.

I have a short video of my line which includes a trip through the tunnel when it was new about 4 years ago.
http://www.zen116491.zen.co.uk/trains/Garden.html ( scroll down the page to get the video)

The tunnel is about 4ft long and basically I cut it through a pre existing rockery. First removing any rocks that were in the way, then digging a trench to some 9" below eventual track level.  3 or 4 inches of hardcore were rammed into the bottom, then some 2nd hand 'rosemary' roof tiles were placed on end, side by side, along both sides to form the tunnel walls, then concrete was poured in to bring it up to track level. 2nd hand slates were used at both ends as the roof, mortared to the top edges of the tiles. This left a gap in the centre slightly less that the length of one slate. A slate was laid over the gap and 'fixed' in place with silicone sealer, this designed to allow emergency acces if ever needed.
Finally, suitable stones and soil were arranged on top to recomplete the rockery.

The tunnel mouths are made of slates, with the mouth cut out using a a tile saw. Then a small rockery stone was sliced into suitable sized pieces and the tunnel mouth faced up, using waterproof tile cement and waterproof grout.
They have both been outside through 4 winters with no failures so far ( fingers crossed!).

Hope this helps

[MDLR]

Another way which I used on the MDLR was to put down a concrete base wider than the eventual tunnel, build a wall one concrete building block high, and add a semi circular half drain pipe, upside down, for the roof.

[mightymax]

Thanks chaps, some good ideas there. Love the cab ride video on your railway.