Tunnel Construction

[dandylines]

Don't forget about one of the simple, cheap and easy ready made shapes for a tunnel out there. The standard #2 rural mailbox.

[Anonymous]

We used treated wood painted with waterpoofing paint then made the tunnel portal with belgin stone. Our tunnel is curved and we almost used cement blocks, but chose the wood since we had the wood on hand. Flue liners would not have worked well for us because of the curve.

mikadousrp

[Capt Bob Johnson]

Everything i read says to make tunnel bigger than you really need in height & width, that way you can accomodate some new type of car that comes out 10 years from now, and easier to manipulate derailed cars to get them out. I'd go with a minimum height of 12 inches and width of 8 inches. You just make your portals the size you want people to see.

Much wise advise has been given here on length. that is unless you have some way to put manholes into it and figure out a way to hide them in the scenery.

Keeping wildlife out? Try the 4 inch thich upholstery foam cut about 1/2 to 3/4 inch bigger on all sides, with a chunk of plywood on the back and a knotted string thru plywood, foam, etc. and sticking out to use to pull with. When not running insert plug; and just pull out to run. Had a friend used that to keep birds from nesting in airplane engine cowling. Worked very well.

[Anonymous]

I used three metal mail boxes mounted on a treated board and covered them with plastic. The size is perfect and so is the shape. I bought plastic tunnel portals which fit the openings perfectly, confirming the dimensions and shape of the mailboxes. I cut off the rear ends of the mail boxes and used duct tape to cover the small gap between each. I nailed each box to the board below for stability. Looks great, works great.

[Anonymous]

Hi figure8
An Aster 4-6-2 and a train of 16 Basset Lowke scale model (for thier time) G1 tinplate coaches.
Adds up to a fair bit of weight traveling at express speed.
the rabbit didn't stand a chance no where to run too.
the train did not suffer any damage.and the rabbit did not suffer but the locomotive got its frame bent.
regards John

[Anonymous]

Oh my god, John, the pet rabbit was killed by the toy train? That's something I hadn't ever eard of before.

Here's a tip about keeping things from living in your tunnel: I hear that some people use removeable plates, plastic curtains, or whatever, across the entrances to their longer tunnels. They just move the plates/curtains into place when not running trains. Might save a lot of hassle of an infestation.

[markperr]

On the subject of tunnel liner material, here's what NOT to use. Pink foam, the rigid stuff used on concrete walls. I used this in one of my tunnels and covered it with chicken wire and then rags soaked in morter. The tunnels are just not rigid enough to put any weight on them without their collapse. I would highly recommend the use of more permanent materials like wood or concrete.

Mark

[markperr]

I'm going to go out on a limb here and say that PT wood will not harm your plants. I have several anecdotal reasons for saying this. One, I have seen lots and lots of PT planters with beautifully flourishing arrangements growing in them. Two, PT wood is made for direct burial as it is the wood of choice for use in deck building. Even decks made from cedar and redwood generally use PT lumber for structural elements that will not be seen. And three, with all the tree huggers employed by the EPA, if there were actually a credible threat to both the North American Cockleburr plant (that thing that everyone's dog's love to run through) and the Milkweedus Profundus, then the use of PT wood would be history.

Creosote, on the other hand.... in the words of the Emerald City Taxi driver as he said to Dorothy Gale..... "That's a horse of a different color!!!!!"

Cynically and with all due respect to the non-tree hugger EPA types,
Mark

[Anonymous]

try useing 4x8x16 cinder blocks standing on its side then topping off with 1x8x16 for the roof then cover with plastic or rubber pond liner and cover with dirt, rocks, ect to your liking

[Anonymous]

QUOTE: Originally posted by Butzer

concrete block worked well on our garden railroad, we put concrete 2x2 paver sections with geofabric on top of that to prevent dirt falling through paver joints.

-Hammer

Does the geofabric work well, and how much dirt escapes without it?

[Anonymous]

concrete block worked well on our garden railroad, we put concrete 2x2 paver sections with geofabric on top of that to prevent dirt falling through paver joints.

-Hammer

[d4fal]

Treated wood, depending on how they were treated, could harm plants, I'm afraid. Creosote if used certainly can. Check to see what method was used to treat the wood, and if leaching into the soil is a problem. Untreated wood might be useful for very temporary tunnels. I've even tried slopping a layer of cement/sand on top of the plywood construction once, but I did not notice if this trick worked, as the line was later replaced when I had re-aligned the right of way and built a more permanent structure.

[Anonymous]

i use cement block, with a metal cover over top,
or use concreate caps.
then pain the inside black, after you are done mudding it up,
then attach your portals to face of cement blocks.

good luck, andy

[Anonymous]

Tim,

Make sure and post pictures of your finished tunnel. Looks very interesting!

Thanks,

BTH_RR

[Anonymous]

Here's a thread on my tunnel project:
http://www.mylargescale.com/forum/topic.asp?TOPIC_ID=20558

[Anonymous]

I've got 2 screens that fit over the ends to keep the rabbits out.

[mryombee]

Another idea I have heard of is to use a plastic 15 inch culvert. It can be bent if you wish, but as stated, make sure you leave access from the top just in case you need it, and don't forget to punch holes in the bottom for drainage.

Also, I read in an article someplace that if you make some sort of a plug or drape somethng over the enterance and exit when you are not running the railroad, it will help to keep out the critters and leaves.

[Anonymous]

hi y'all,
I'm tryin to do the same thing, and all I know is that a tunnel should NEVER be more than two arm lengths long (if your train de-rails, a hedgehog thinks its a hibernation hole etc.etc.)
hope this was of some help,

[nalts]

Thanks for the advice Blue. I'll have to see what I can get away with next time I stop by the construction site. Hopefully they will set aside their throw-aways like they said they would.

Chris

[Anonymous]

IMHO I would get all the sizes. Small to very large.
Helps to have a stock of it unless you want to go and buy a whole pipe for only a needed section of 3'.
I raid plumbers when I see them. I just ask for any bad pipe, brass or plastic.

[nalts]

QUOTE: Originally posted by Marty Cozad
OH be sure to allow for the roadbed height. note the gundersons just fit.
http://1stclass.mylargescale.com/NTCGRR/ditchlight3%20001.jpg

Very nice Marty-

Being a newby to the hobby, I'll ask the obviously simple question. How much height do you need? I haven't seen the gundersons in action yet but would like the possibility of adding in the future. What is the height of your portals before laying ballast?

Thanks,
Chris

PS: As a side note. I stopped by a local construction site where the city is putting in water and sewer for a 600 home development. There is pipe everywhere!

I took the advice of a previous poster and spoke to the forman about getting some of their throw-aways. Looks like I'll have my choice of sizes and lengths for only the cost of some beer.

What is the minimum diameter I should get? I know I saw 12", 16", 18" and possibly 24". Also wondering if anyone runs a double mainline through a tunnel? Any suggestions or additional thoughts on size?

Thanks in advance,
Chris

[Anonymous]

JEFF
I ALSO USED A CHIMNEY FLUE LINNER YOU CAN PUT 2---3 TOGETHER AND USE STONES TO HIDE THEM LIKE A MOUNTIAN . BEN[2c][:)]

[Anonymous]

Last week I ran into the foreman of our local waterworks dept. He offered me a 12" x 14' (foot) PVC watermain pipe. The only catch was that the end was full of concrete. A portable generator and a sawsall made easy work of lightening the load in about 5 minutes. And best of all, I only had to cut off about 8 inches from the end.

After I got it home and cut it to the desired length of 66", it still weighed in at about 150 lbs. The wall is 1 inch thick! It's definetly not going anywhere! And I still have another 8' left....WOOHOO[:p]

[Anonymous]

i am using the chimney flue linner. its 12x 24, it works great. my only complaint is the longest they make is 24 inchs.

but its workin out just fine.

Jeff

[Anonymous]

hi trainmaster1989
Just a small caution to add to the list make the Tunnel far larger bore than
is required the trend is for larger locomotives.
And if you win the lottery and decide you want steam power they tend to be a little larger bur not much than most G scale stock there are as always exeptions.
Oh and if you have a pet rabbit keep an eye on it a friend of mine had to explain to his very young daughter why floppsy was an expired rabbit
head on with heavy steam train in the tunnel
regards John

[mkblk]

[smcgill]

I'm going to make one with concrete blocks-just set dry with some roofing felt on top that I have laying around.I'll set the 16" pavers 6" in the ground (there against the foundation) and use 12" blocks on the outside then set 16" pavers across the both. I'll then cover with the felt and dirt. This will give me 12" before I ptu in track.I'll get to the potals @ some date.

[Anonymous]

QUOTE: Originally posted by d4fal

Depending upon scale, of course, and how big you want this tunnel, the most important part is how the portals look and the functionality of the lining that no one should be able to see anyway. As long as it supports the load above the tunnel, almost anything would do. Temporary tunnels could be mocked up with plywood covered in plastic then overlaid with the dirt covering. Once this is done, and you decided that you like the placement, clearance, etc., you could consider a more permanent structure. In my scale, that is a formidable project, but in G-scale it could be done in pressure treated lumber, and depending upon budget and how long you plan on keeping the tunnel there, you could use a water proof liner and exterior grade plywood. Doubt concrete is really called for in this scale. Seen timber type construction done with treated boards, but that is frowned on in a garden where the treated wood could harm your plants.

Can treated wood harm plants? My tracks are screwed down to pressure treated wood and plants are around it. It has been a year and no plants have been harmed by the wood. Are the plants going to die later on?

[ondrek]

QUOTE: Originally posted by trainmaster1989

I would like to construct a small tunnel into a dirt mountain on my garden railroad. Unfortunately I don't know what type of lineing i should use.
Scott

The Train shop down the road used a square chiminey flume for the tunnel walls and support. it seems to be working really well. they say you can get them cheap if they are cracked a bit. they cant use them for consrtuction, but we can, infact they said to put the cracked side down and its great for drainage.