Tunnel Portal Issues (help!)

[nik_n_dad]

Hello.

 

We're building our n-scale layout (based on Kato double track Unitrack, with superelevation) and are finding that the common tunnel portals don't provide adequate clearance for double-stacks, autoracks, etc when you try to enter or exit on a curve.  Our trains either hit the top of the portal, or if I shim it up by about 3/16" the cars will clear.  BUT, long cars with their overhang will hit on the portal too.

 

I've looked at using HO, but the size just looks goofy.

 

We're freelancing our layout and run everything from steam to bullet trains and everything between, so creative options are welcome.

 

Along this same theme, we'd like to have part of a city scene that's built over the double-tracks mainline.  Since we're having trouble with portals, is there something else we can do for where the trains would enter the tunnels under the city?

 

Thanks.

[railzilla]

You can make your own portals quite easy if you choose modern concrete portals.

Instead of a tunnel you could run the track in a trench. Prototype Railways run often in trenches when they cross a city. For non electrified systems like US prototypes this is preferred because of ventilation issues in tunnels. Streets can cross easy via short bridges. You also will see you train longer than if they run in a tunnel.

[Bernard]

N&D - Can you post a photos of the tunnel portal problem. One of the portal by itself and others with the trains hitting the sides illustrating the problem. This way members will get a view of the problem and make suggestions for smooth running. 

[qwertyaardvark]

Photos would indeed help almost as much as telling us what particular make and model of tunnel being used. This is pure conjecture, but by "common tunnels" do you mean Japanese style tunnels, like a Greenmax tunnel entrance? Those may pose a problem since in Japan containers are not double stacked since it's too high for too many height constraints (catenary, tunnel clearances, etc). An American style tunnel, perhaps something like a Woodland Scenics Tunnel, might be designed for a market that often caters to people running tall and long wheel-based double stacks and car racks.

[CaptOblivious]

I too have problems with Greenmax portals set on a curve. My shorter trains just clear them, but anything shinkansen length scrapes the sides. Could you get a double-track portal, and shim it up higher? Or perhaps, if the line is a double track line, cut the portal in half and extend its width? Scratch-building poured concrete entrances would be easy, too, basically just a square opening.

[bill937ca]

For those modeling Japanese trains (not the high-stackers) here's a Japanese language article on making a tunnel of towel.

 

http://www5a.biglobe.ne.jp/~toyoyasu/ttunnel_1.htm

 

http://www5a.biglobe.ne.jp/~toyoyasu/ttunnel_2.htm

 

There is a PDF template for making tunnel portals with styrene foam board.

 

http://www5a.biglobe.ne.jp/~toyoyasu/ttunnel/towel-tunnel.pdf

[inobu]

This may be the easiest and most adaptable portal.

 

 

 

You should be able to cut a soap detergent bottle to give you this arch. Then plaster the edges. I think its ideal because the slanting gives you a buffer into the mountain. 

 

Inobu  

[disturbman]

Wow!!! That's a very interesting suggestion Inobu.

[nik_n_dad]

Railzilla's comment's really got Nik & I to thinking about our layout today.  Because we've been trying to stuff as much railroading into the space we have, we settled on an around the walls layout.  But, as Railzilla pointed out, we don't get to see out trains much- they're always behind some part of scenery.  (If you could walk around our layout that would be fine, but we can't, since the layout goes up to the walls).

 

Soooo..... we're sort of back to the drawing board and reconsidering what we've been working on.

 

Ok, to the other questions (and thanks for all the ideas)

 

#1, We've tried Woodland Scenics & Chooch brand tunnel portals.  No luck on either.  If we set the portal on about 3/8" (9.5mm) we can get the height that allows modern autoracks and double stack containers to make it through heigh-wise (our Japanese passenger trains, shinkansens', etc run fine even without the shims).  However, longer cars (the auto racks, some passenger cars) will hit the inside edge of the portal with their overhang on the curves.  If we move the portal over to get the clearance, the other side now clips the tops of the container cars.

 

#2  Haven't tried Greenmax- other than plaza japan, we can't get that here, so it's a bit harder to get to try

 

#3  Thank you for the do-it-yourself portal tip, Inobu.  I think Faller in Germany is releasing a portal like that, but it's not available yet.  We may try to handcraft one as you suggest.

 

#4) Our style of model railroading is very eclectic.  Everything from American steam to Japanese shinkansens & commuters to German trains from the 30's to modern freight and honestly, anything that (as Nik puts it), looks cool.  So, needless to say, we free-lance alot.

 

In the mean time, it's back to the drawing board.  "Mom" is aware of our frustration, so she's letting us try a different room for the layout as well.  Wish us luck on a new design that meets Nik's style of railroading, fits "Mom's" allocated space, and doesn't drive "Dad" batty in building.   

[Mudkip Orange]

edited for content --- mudkip

[Bernard]

Dad (because Nik isn't going to be able to do this) this is what I did to modify a Woodland scenic double portal.

Here is the link to the portal I used:

http://www.modeltrainstuff.com/Woodland_Scenics_N_Double_Tunnel_Portal_Conc_p/woo-c1156.htm

 

Then what I did which you will see in the 1st photo I flipped it over and drew part of a circle to try and emulate a Japanese portal because they are round in appearance.

The portals from WS are made from Plaster of Paris and can be grind into shape. I took my Dramel drill with a grinding bit and did just that and then smoothed it with sand paper. The last part was to stain in with gray pigment. The 2nd photo is the portal finished and installed into position but before you install it, test it that there is clearance with all your trains, if not grind some more.

[IST]

What are you thinking about the ICE tunnel portal from NOCH? Product number is NOCH 34840. Here is a link how it is look like. It is 12,5*10 cm.

[nik_n_dad]

IST:  I hadn't seen the Noch version of the ICE portal.  Here's a link to the faller version that's not out yet:

 

http://www.euromodeltrains.com/cgi-bin/search_item.pl

[nik_n_dad]

Bernard-

 

Thanks for sharing the photos and tips on modifying the portal.  I may try that when we get going on the next major revision of the layout.

[nik_n_dad]

Mudkip-

 

I can live with stupid remarks, but I don't like having to try to explain to a 10-year old looking over my shoulder what your comment means without actually answering him.

 

I guess this isn't an appropriate site anymore.

[Mudkip Orange]

I can be pretty flippant at times. Sorry for any offense.

[Hobby Dreamer]

Hi

 

the link for the Noch portal does not seem to work so here is one:

http://www.eurorailhobbies.com/erh_detail.asp?MN=15&CA=23&SC=N&stock=NO-34840

 

I bought an ICE II (a German high speed train) some years ago in N scale and planned to use this type of portal, but stupid me for getting the ICE II and not the ICE III which seemed too futuristic at the time - what the hell was I thinking! (the photo shows an ICE II, but the III looks a lot like the Sonic - very cool!)

 

I've been thinking about using an HO version of the portal, which should be large enough for Kato's track and road system.. 

[scott]

I like Inobu's idea--I had been thinking of trying something similar, maybe with PVC pipe scraps cut at an angle.