Tunnel Building

[Brober]

Hi there all,

 

I am new to this forum but have perused for a while and have picked up a lot of info in the passing.  I do have a problem with which I would welcome any assistance that may be available.

 

I am hoping to create a mountain scene with an adjacent quarry.  I have a double branchline (OO Gauge) that I would like to pass through the mountain.  The problem I have is that the area of my layout that I want to use doesn't allow me to gain access to the tunnel insides should a derailment or any other unfortunate accident happen.  Is there a clever way to form the mountain over the track that would allow me to be able to remove a section of it, that is not too obvious to the casual observer, to deal with any mishap ?

 

Any help or advice would be very welcome.

 

Brober

 

 

[Pete the Elaner]

You will need to make it in sections. I guess the issue is hiding the joins between each one?

I was at a club some time ago & a layout there features a large hill which the line passed through. They cut large holes in the baseboard so you could reach from below & grab anything you could feel. The drawbacks of this were that stock could derail & hit the floor and that daylight would be visible through the tunnel, which is a pet hate of mine.

Adding some form of cover or door beneath the holes would address these issues though.

[HLT 0109]

It is possible to do almost anything given the right inspiration and suitable materials!  I have a tunnel that is about 6ft long and hides a sharp curve; it is made in several removable sections and, becausse it is a rural hillside, the vertical joins can be hidden or camouflaged with scrub and bushes, or made to look like fissures in the ground.  In my case, I also wanted to hide the join with the ground and made that section on a stout piece of paper which protruded about 10mm along the base - that was then painted like the surrounding ground, taking care not to stick it to the baseboard when placing scatter on the adjacent ground.  The section has been removed a number of times and remains effective.  I have looked for phoitographs but have nothing worth posting.  Sometimes it is a question of planting shrubbery so that it sits over the join - but then you have to ensure that removing and replacing the sections is done in the right sequence.  My tunnels (like most of the scenery) is made from polystyrene sheets/blocks cut with a bread knife and stuck with PVA glue.

 

I hope this is some help.

Harold. 

[Brober]

Many thanks to both for your comments and suggestions.  I do not think the "holes in the baseboard" solution would work very well for me. Below the baseboard are a couple of bus wires and a myriad of droppers.  Also I would probably still need topside access for rail cleaning (don't have a mobile one).  Harold's suggestions are more in keeping with what I was coming round to thinking would be the best solution. Foliage is not possibly the finish that I was hoping to have as the "hill" is intended to form part of a slate quarry and by its nature is quite devoid of vegetation.  I may have to revise that thought though. My layout is a permanent one so I don't need to vertically join sections together. But I will need to have a lift out section to allow  access into the tunnel.  My thought is to have protruding strips each side of the lift out section painted and finished in scatter to match the surroundings. Hopefully I can do this sufficiently well to mask the joins.  I am thinking of using polystyrene sheet/ blocks to form the hill profile and tunnel void and surface with plastercloth over as necessary, plastering that and then applying scatter etc. with PVA.  Unless there are any other suggestions forthcoming!

[barrymx5]

I have a similar problem and tackled it by creating a complete lift off section. So the “walls” are sceniced with a lip of vegetation etc. The photos below show construction a couple of weeks apart. The scenic grass sheet is still to be trimmed in the first photo.

Hope this helps. Hardly original but it works.

[DCB]

The holes in the baseboard is a bit naff, I would cut the baseboard surface away completely under the hill and put 1/2" high sides on the trackbed to stop errant stock escaping. I have a long length of track in a trough with 1/2" high sides en route to my lower hidden sidings which works well, just a couple of inches wide in places with a thirty inch drop to the floor

Droppers and bus bars sounds like a nightmare, sooner or later you are going to need to replace the tracks or pack them so I try to avoid any wires below the track bed in tunnels, run them on the surface.

I would make the main hill as light weight as possible and have it simply lift off., Fibreglass rather than chicken wire and papier mache or mod roc.  Fix the scenery down well and hide the joints with dry stone walls, if the join is behind the the wall from the viewing side then you can't see the join. If you want removable vehicles etc then insert super neo magnets in the road surface etc under very thin card and similar under the vehicles, you can get about 50 for £1 inc postage on eBay. obviously north to south unless you want to model hovercraft.

Many proprietory model Tunnels are too wide and not tall enough for scale due to the very wide 60mm set track track spacing against about 44mm scale or 50mm Peco streamline

 

I find its very important to keep tunnels dark, a lining following the tunnel mouth profile for a few inches works really well but the light/dark only really works outside, the tighter the tunnel mouth fits the stock the easier the problem, I'm not averse to tunnels entered by a road bridge with bare 15ft clearance, one had to be made bigger when I tried to run a GWR King thats how tight mine are.

My big tunnel needed a 2 foot deep six feet long trench under the garden and a long length of plastic pipe. the track bed is on a wooden batten and can be slid out for maintenance, but hasn't needed any in over 20 years, but I use battery power outside

[DCB]

Duplicate sorry 

Edited January 26, 2019 by DavidCBroad