Jump to content

Recommended Posts

So, I have decided to build a tunnel. I have the tunnel ends, and I know that I need to extend the base area on which the tunnel will sit... The question in, how do I BUILD the tunnel. It has to be 2 meters long, on a straight. I also know that it has to be water tight, so plan to build it around a length of black drainage pipe.

I also want to line the inside wall with some white LED lights.

At 2 meters long, it should be easy to clean with either a gauge master track rubber on a stick or the dapol wagon (or both).

But how do I build the main "bulk" of the tunnel with a material that wont perish...

I do know that I want to "dress" the hill a bit as its going to be the only true scenic in the garden, but not in the usual manner.... Im thinking of using some of those nice creeping conifers that spread out over a flat surface as oppossed to grow up... and that will be the main purpos of the tunnel, to provide a good base for the plant to establish over. So, whats the best way forward.... keeping everything safe and simple

Ta

Link to post
Share on other sites

so this is my idea....

fan out the base a tad, guttering for the main enclosure.... sealed and water tight. Then the main shape from carved Polystyrene which is then rubberised and then sealed with fibreglass cloth soaked in expoxy resin

This is then coated in smaller peices of the cotswold bluff gravel and then from behind, a creeping thyme and other suitable dangly plants can come up and over the tunnel as they establish...

 

tunnelidea.jpg

I may opt for 1.5 - 2 min length

Link to post
Share on other sites
Quote

Then the main shape from carved Polystyrene which is then rubberised and then sealed with fibreglass cloth soaked in expoxy resin

I'm not sure but I've got a feeling that the resin may dissolve the polystyrene. I think you may be better using polyurethane foam. You can buy it in slabs from DIY stores and you can even buy the expanding variety in cans.

Link to post
Share on other sites

cool. I have decided to do a materials test at the weekend (if this rain will ever let up....!)

Finally got round to replacing my old Airfix GMR BR class 31 yesterday with the weathered hornby version, so dying to give that a run too.... but the rain and wind down here is just ruining all plans

Link to post
Share on other sites

My main advice is to make sure it is accessible - I did and I haven't regretted it! Mice, slugs, woodlice and everything else will find their way in somehow, and may be impossible to remove without good access. My tunnel is about 5' long, goes under a path, was made by the cut-and-cover method capped with removable paving slabs on top of building blocks, and has a removable liner made with inverted guttering encased in expanding plastic foam with rope handles on top and the cosmetic portal attached at each end. A few pictures taken during construction are at http://fungusmodels.blogspot.co.uk/2011/08/tunnel.html" onclick="window.open(this.href);return false;. Good luck!

Link to post
Share on other sites
  • 2 weeks later...

I have heard that a tunnel should never be longer than two hand to elbow lengths. If you provide good access you can have it longer but try to bond the rails only once you've got the walls up. If you find you have trouble bonding the rails you will require a rethink on the tunnel construction. You could make a test tunnel to try out your idea of what you want then if it doesn't work out you haven't got a permanent structure that's unworkable. Trevor Jones has tunnels on his garden railway as says that his only regret is that he has rail joints in the tunnels and it extremely hard to rebond them if bonds drop off in the winter.

Roy.

Link to post
Share on other sites
  • 1 year later...

Are you not tempted to line it with pond rubber on the outside just to make sure, because once those wood sides start to rot in all that moisture, you may find your seal is easily compromised, and then its back to the back ache of digging it all out again.

Link to post
Share on other sites

Sorry Guys

Forgot to explain the materials, the yellow stuff is mains gas pipe about 1 inch wall thickness and 8inch id, the white stuff is plastic fasia board cut to size and the track bed is 1inch tanalised timber treated to several coats of bitumin paint. All the joints are to be sealed with mastic and when the tunnel is in place it is covered with heavy duty builders membrane then buried.Hopefully this should keep out any water/soil ingress. Sorry for any confusion this may have caused.Regards Mick.

Link to post
Share on other sites

Now, That looks like a tunnel!

Maybe I missed something in another post, but is there an access for cleaning the track/clearing windswept foliage/animal droppings?

All my hidden sections have a removable top. We have lizard droppings that form into hard pellets... One cause of the broken drive shaft I think on a derailed class 47 (mentioned in an earlier post).

Or maybe I'm missing the perspective and it's all reachable at arms length.

Link to post
Share on other sites

Hey Ba14eagle

The track bed is screwed up into the gas pipe and the strips of fasia board are just a bit extra. This tunnel is the one that was on my G-scale railway and has been buried for a lot of years so it should do the job ok. Thanks for your concern. Regards Mick.

Link to post
Share on other sites

This looks great. A proper outdoor structure using materials that will last for years.

Grif's idea of a rerailler is an interesting one. I'd have never thought of that.

A thought on bonding. I have suggested elsewhere on here that tunnels may benefit from a belt and braces attitude to bonding and that two bonding wires should be added to each rail join, but looking at your photos has given me a different idea. We bond close to rail joins to keep them short and unobtrusive, in a tunnel they can't be seen. A bonding wire that runs from one tunnel mouth to the other wouldn't look out of place. The solder joints would be accessible and could be maintained.

Link to post
Share on other sites

Hi Chris

The bit I forgot is the bit you mentioned but I can get over that problem by threading some cable through the tunnel and stapling them to the track bed and then solder to the next length of rail. Funny how someone see's what you were going to do but forgot to do it. If there is a vacancy for a remember engineer you have got first refusal. Thanks mate. Regards Mick.

Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...