# Suggestions for tunnel materials



## mickey (Jan 28, 2009)

I am in the process of building a tunnel which will encase a a quarter of a 5' radius turn. I know that is long but plan top access in the middle. It will be buried under a couple feet of gravel/dirt and later access to fix any issues would be a real pain in behind. I had planned to build it out of the flat cinder blocks stepping stones mortared together, but I am concerned the sides may just collapse inwards with the pressure of the ground around it. The only plastic culvert pipe I find that bends will be way too stiff to make that bend. Considered the clay flue liners, but that is a lot of cutting to make the turn. Any other suggestions?


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## Andre Anderson (Jan 3, 2008)

Oh I seem to remember JJ







casting one out of concrete and then trying to move it.







.


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## jimtyp (Jan 2, 2008)

I've seen where some have used a chimney flue ->  link to pic


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## bob7094 (Jan 3, 2008)

I made a box of 2x10 pressure treated wood, with the ends left open


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## livesteam53 (Jan 4, 2008)

Weather you make it from treated wood, concrete block or whatever is handy. 
You need to place a water barrier over the frame with it curved out at the bottom so you are water proofed and not getting water running in your tunnel. 
You can use some heavy tar paper or heavy plastic.


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## Madman (Jan 5, 2008)

If you are building it on a curve, I would suggest using brick. They can be laid to suit the curvature of the track. Once they are set in mortar, there would be little chance of a collapse. Just be sure to provide a good foundation. The foundation can be modified crushed stone, tamped and leveled. Or you could pour a concrete foundation. The suggestion of waterproofing the tunnel is an excellent one.


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## Dan Pierce (Jan 2, 2008)

I used the serated aluminum 12 inch drainage pipe. 

I did not worry about water as I used 1/4 inch gravel for ballast 1/2 inch deep under the track. 

I made sure I used a 5 foot flex track through the tunnel to eliminate any track connections inside my 4 foot tunnel. 

Also, by chance the tunnel has a wind rip through it and I have had no critter issues with it in the 8 years it has been used.


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## Matt Vogt (Jan 2, 2008)

Most of the corrugated pipe is, indeed, to stiff. However, if there is a pipe supplier near you, you might ask about single-wall pipe. I have found some that did not have the inside liner that is flexible enough to do what you are asking.

Good luck, and keep us posted,
Matt


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## Daniel Peck (Mar 31, 2009)

On the flexable pipe deal you can make cuts on the short side of the radius from top to bottom and it will make the pipe flex a little more easy.


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## Biblegrove RR (Jan 4, 2008)

I used 12" curragated plastic pipewith sprinkler boxes for access.


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## pcz (May 13, 2010)

Ciao from FRA&PIE route.

I built Dry Chute, Laurel and Curved tunnels in structural polystyrene.

I painted in flat black and, when dry, with a thin film of vinyl glue.

When buried under feets of gravel, you can walk on it safely.

More info, schemes and images here: http://www.zuccarello.com/fn3/CurvedTunnel

Regards.
Pier


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## cape cod Todd (Jan 3, 2008)

I built a 15' long tunnel around 5' diameter curved track. I used a base of gravel for drainage and cinder blocks, the 4"x8x16" ones and cemented them together. I was hoping to be able to use a large patio block for the roof of the tunnel but once I looked at the swing of my largest equipment around the 5' curve and the blocks were placed to accomadate this I ended up using plywood. I cut the plywood to overlap the edges of the blocks, doubled it up and screwed it together. It looked like a giant horseshoe. I then painted it and wrapped it in heavy plastic. It is now only a couple of inches under the dirt but I can walk on it without worry. I also cut in 2 hatches at appropriate sections in case of derailments. So far so good. I have another tunnel that looks like an 8' long candy cane made entirely out of plywood which has been buried now for 4 years and it is still in good shape. For straight tunnels I have used 12" flue liners. 
Good luck.


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## mickey (Jan 28, 2009)

It has to be a 12 foot long 1/4 turn using 10 diameter curve with about a 4 foot straight heading into it. There is no way around it to make things fit the area, walk, existing cement, beds, etc. The top of the tunnel will end up being about 12" to 18" below final dirt grade. I know I will have have 1 top access (maybe 2) just in case as it will be totally buried on all sides. I have not been able to find any of the 12" plastic pipe that will bend enough to make that curve. I have pretty well decided to just pour a foot wide footing and then use the 2 inch flat cinder steps to make the sides and top. They have some at Home Depot that are already variegated brown so the inside will look better should I ever want to take some pictures as it goes through. They are not that much more for the relatively few I will be using. I am concerned with the sides pushing in due to the weight even though they will be mortared in. What are your thoughts on that?


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## Biblegrove RR (Jan 4, 2008)

ANY hardware store has single wall, black corrugated plastic drainage pipe


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## mickey (Jan 28, 2009)

Not around here. I have tried everyone I can find including in San Antonio. Everyone says that 12 inch will all be double wall and not something you can bend. Any other suggestions.


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## Biblegrove RR (Jan 4, 2008)

call a contractor, they will know for sure. Even better if you go up a size and still be single wall!


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## mickey (Jan 28, 2009)

I have checked everywhere including national suppliers and they say the only demand is for the double wall which will not make the radius. I wish I could find it because it would really make my like much easier.


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## Biblegrove RR (Jan 4, 2008)

you can TRY calling Energy Culvert and see if they will ship you some? What is NICE is everywhere I go it's 20' minimum and hard to haul. This place offered it to me in any length I wanted! 
(618) 942-7381 Energyculvert.com 

over


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## mickey (Jan 28, 2009)

Talked with Charlie over there and he found some here in Texas for me. I will head over for the 2 hour drive to pick it up this week. Hope it works but will let you know. Had to buy a 20 foot stick but only $105.


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## Biblegrove RR (Jan 4, 2008)

don't forget a sprinkler box every 10' or less. I just priced 20' at my local Menards this weekend at $98 so you're not getting a bad deal. Maybe there is a train store on your 2 hour trip? lol


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## mickey (Jan 28, 2009)

I will take some pics as I go and show how it ends up.


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## Biblegrove RR (Jan 4, 2008)

Mickey, what is the status on your tunnel?


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## Biblegrove RR (Jan 4, 2008)

Mickey, what is the status on your tunnel?


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## mickey (Jan 28, 2009)

Things got bogged down doing the outdoor fireplace so I hope to get back to it soon. I will try to figure out how to post pics and get a few up. I am excited about the prospects of getting back on it.


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## Biblegrove RR (Jan 4, 2008)

wow, i would even enjoy pics of that too! Always wanted one but will have to settle for a piece of 4' metal drainage pipe 1/2 buried in the ground. Any questions about posting pics, just ask...


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## mickey (Jan 28, 2009)

I cant seem to find where to add pictures. The FAQ only mentions for 1st class. Is that the only way other than a link to some site? 

For now at least:

http://www.dilloware.com/IMG_0516.jpg


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## Biblegrove RR (Jan 4, 2008)

If you have not paid for 1st class status membership... DO IT! No really if you want the full benefits this awesome site has to offer, like being able to post pics. I do think you have to step up to 1st class status... ? Anyone else following this thread want to encourage it ?


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## SteveC (Jan 2, 2008)

Since you've got your pictures available across the Internet then all you need to do is manually type in the HTML code to include the picture in your reply, see the following image if you don't know the HTML. The other thing is the maximum dimensions for displayed images are 800 x 600 pixels.


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## Biblegrove RR (Jan 4, 2008)

Mickey, that is an aweful tight curve and will cause you problems. You need to install an access port there (sprinkler box)


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## mickey (Jan 28, 2009)

It may look tight, but is actually a 10' diameter (5' radius) curve. I actually laid out the track and used orange marker paint to give me a line to follow with the pipe. Part of the delay has been letting the pipe bake in the sun to keep its curve as it is bendable but has some strength and memory to it. When finished, there will be the gravel up over the top by several inches then a foot of dirt. But I already know Murphy's law, so at least one if not 2 access ports. I have an extra 10' of pipe so I plan to create a saddle (just like welders do for pipe joints) and bring it up to a box, then seal the joint to make sure it never rains inside the tunnel. The tunnel will end up being being about 15 inches from it's top to top grade of dirt. I plan to use some mortar to create an semi seal when it meets the rock to minimize water and dirt falling through the gap. At least that's the plan as this is a work in progress.


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## Biblegrove RR (Jan 4, 2008)

Looks great! keep us posted


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## Totalwrecker (Feb 26, 2009)

I hope you have gumby arms! 

I covered a 1/4 turn of 10' d track with a bench and a small platform. There is one access hole in the center no more than a foot off the rails. 
My derailments never happen under the hole, that you can take to the bank! Every time my shoulder gets stuffed into the opening trying to reach the car/loco. There's no way to try and rerail em so it's the 0-5-0 big hook to manuever it out of the hole. Mine is a rectangle 5"x12" and it's a little tight depending on my grip. 
Chances are that your cars/locos won't bend to get out your access hole and you may have to rersort to pushing them out as best you can. Provided your gumby arms can bend any which way! 

John


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## mickey (Jan 28, 2009)

That is exactly why I'm considering 2 access holes. I'm assuming it will usually be a push 'em out situation. I would have prefered not to have such a long tunnel but the area required it to get all to work right. I also expect to have to devise some sort of long grabber/pusher too.


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## Ken101Ward (Jan 1, 2010)

I had a Grandma who was confined to a wheelchair. She had an interesting assortment of grabber devices to get things into 
and out of cabinets she could no longer reach. I don't know any of the product names, but I'm sure a medical supply company
who deals with wheelchairs might be a good place to start looking.


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