# Track access inside tunnels



## fyrekop (Sep 20, 2011)

Question: How far apart should access openings be in long curved tunnels?
My site has progressed to the point that I'm beginning to designs tunnels, mountains, etc. Tunnel entrances are set at min. height of 11' with 10" width for single openings and 21" for double tracks. Current tunnels under construction are less than 40 inches long. 
The next planning phase is for the 30' tunnel / mountain at the northwest end of the site which will cover 3 tracks on two levels and I need some guidance regarding MOW access in case of derailments or cars uncoupling unintentionally. After my first open house, coupling issues for longer trains with custom built cars showed that I had to plan for those hopefully rare occurrences on curves under 9' R  I've seen some elegant solutions for access from open caverns and large hidden access panels to framed openings in exterior tunnel walls. Young children with heads stuck inside the openings to watch for trains is not required.
Suggestions, solutions from prior builds, and rebuilds gratefully accepted.


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## Dave Meashey (Jan 2, 2008)

Fyrekop;

A friend of mine had three tunnels on his layout. All of them were relatively short. I think the longest one may have been six feet, and all of them were curved. He had an access hatch that was one foot to 18 inches long over the center of each tunnel. The hatches were "scenicked" with buildings, figures, and other details to make them blend in.

I remember he told me that one time he was doing his initial spring run and maintenance, when he noticed that the train had not passed by for some time. He found the train inside a tunnel with the locomotive right against the front of the shell of a very awe struck tortoise! After that he also built plugs for his tunnel portals.

Your results may vary.

Best,
David Meashey


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## Scottychaos (Jan 2, 2008)

Measure the distance between your shoulder and your hand.
double it.
That is how far apart your access hatches should be. 

Scot


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## chuck n (Jan 2, 2008)

Alan

For your long tunnel along the back I'd think about bringing the mountain on its back side down to about a foot of the ground. Most people will be viewing the train from the house side. If you don't like the idea of an open gap, you could attach pieces of canvas with snaps or Velcro to cover the gap and paint it to match the rest of the mountain.

Chuck


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## SD90WLMT (Feb 16, 2010)

Have some ..some time visiting your layout Alan...
You might easily consider a back wall...access hatches every so often to peak inside..think about track maintenance also..

With your back corner tho...you could have a mountain of ever increasing height..stopping for the rear fascia only...rather than a peak ridge that comes back down ..

I'm open for some of my usually arm waving design suggestions in your back yard..pow wow free style. Buddy...!!

SD...


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## Totalwrecker (Feb 26, 2009)

Kinda depends how far you can reach sticking your arm into the hole, then reduce by 6". You'll think you now have over lapping reach, except some how derailed trains remain just out of reach.
I had 2 ports on a quarter turn of 10D track.
It's not just touching it, it's having room and control to move your prize beauty without damage.
John


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## pete (Jan 2, 2008)

Simple how far can you reach. My tunnel has three openings. One wear the trains enter one wear they exit and one in the middle. Make sure you can reach your train cars or the train engine if you cannot reach your train you will not be happy Pete


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## CliffyJ (Apr 29, 2009)

How are you constructing your mountains? Dirt / rock over pavers & blocks? Or concrete shell? Or...? That choice of method might argue against certain hatch approaches.


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## John J (Dec 29, 2007)

Mine are 4 ft in length. I can reach a car from either portal. One has a break in the middle. 

JJ


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## NTCGRR (Jan 2, 2008)

I've had lots of tunnels with access and w/o, its far easier to mount a small broom onto a hoe and gently slide it in and push them out.


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## up9018 (Jan 4, 2008)

YouTube Tom Gap's Lone Pine and Western and look how he did his long tunnel. Pretty good idea.


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## Treeman (Jan 6, 2008)

I have two 8 foot tunnels with no access except the ends. Have had to push rolling stock out with a piece of PVC conduit. Not a big deal, 30 feet would be a different story.


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## fyrekop (Sep 20, 2011)

Cliffy, I'm building mountains using paper-mache method (photos in Beginner's Site thread) Not sure about hatches yet but leaning toward framed lift off sections. 
Height and width of the openings was determined by laying on the existing wall and moving a car along the upper level track. 6' sections of wall and 36" wide opening. Not sure of height yet.
Once mountain is built I'll make plugs for all the openings to keep most critters out, although unlikely to run into any turtles here.


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## SD90WLMT (Feb 16, 2010)

Slow moving desert tortises...they're here.
Had regular visitors when I lived in rental trailer..several miles East of where home is now.. They were numbered for tracking...came back each year!!
Wet yet Alan??


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