Track through walls-new construction

[Shreve Rail]

We are designing a new construction model RR building where the tracks (HO) will enter and leave rooms around the inside of the exterior walls by going through the sheetrock.  By planning ahead, I would like to prepare the space between the walls, where the studs are, to keep out dust and have a finished look.  I know how to disguise the entrance portals but what about that 3-4" in the interior of the walls.  Any suggestions regarding this?  Should the track run through a little box-type of tunnel?  Suggestions and experience appreciated!

[gandydancer19]

Any suggestions regarding this?  Should the track run through a little box-type of tunnel? 

Yes. 

I have done this on a layout or two. All four sides should be lined. Both to prevent cars from disappearing, and to prevent dust from drifting on the track and in the layout room. Just cut your hole in the wall, both sides, then you can insert a bottom, sides, and a top of individual pieces in the opening. It won't be easy but it can be done. To help hold the pieces while you position them, you can put a screw in each one on the flat part, but don't screw it all the way in. Leave enough to act as a handle. Hold the pieces in the wall with drywall screws through the sheetrock. You may have to make a bigger hole, then patch the drywall. Once the pieces are in place, remove the handle screws. If you know before hand where the pass-throughs will go, you can make the box ahead of time and install it.

[Johnnny_reb]

When making your portal throw the wall, I would finish the portal completely on the in side because if Murphy's Law kicks in you don't want to have to rip into the wall to retrieve a fallen piece of rolling stock.  The wall portal can be nothing more then a six inch diameter piece of PVC pipe four or five inched long. Just long enough to protrude out both ends of the wall. The bride or tunnel track can be a plate girder or any other type of bridge to span the space between the two. As the track should be supported the the layouts on either side of the wall and not by the wall.

[Shreve Rail]

Thank you both !

[stebbycentral]

We are designing a new construction model RR building where the tracks (HO) will enter and leave rooms around the inside of the exterior walls by going through the sheetrock. 

From your comment above it sounds like the structure is still under construction.  If that's the case, and the drywall isn't up yet, the time to take care of this is now.  Just figure the clearances you need, and frame in the opening with regular 2 X 4 studs like you would do for a window.  Admittedly it would be a mighty small window, but it's a window none-the-less.  Once the drywall is in place you will have your "box".

[rstaller]

 Shreve Rail;  One way to accomplish this, is to use 4 to 6 inch pvc pipe through the wall. Leave enough sticking through each side, to fit as flush as possible with the drywall.  Paint the inside flat black, with a dark gray at each entrance.  Small lights can also be added to the ceiling, or side(s) of the tunnel.  Since the diameter of the passthru will probably be greater than you need, the extra space at the botton of the pipe, can be used for wiring, etc.  Use a thick piece of styrene, or other suitable plastic glued into the pipe, as your base floor for roadbed.  Assemble the whole thing, prior to drywall installation.  Cover the ends with commercial, or custom built portals.  R. Staller

[gandydancer19]

Oh Yea.  Don't forget some way to run some wires through as well.  PVC will work for this, as well as the trains, as others have posted.

[cmrproducts]

When we punched through my sons cement block wall in his basement for his layout, we had the same problem.

We just stuffed some old newspapers in the holes and the sprayed in some low expanding foam.

The hole was now sealed completely and the way the foam expanded we had what resembled blasted rock.

A little gray paint and we were set to go with the track laying phase.

The spray foam cuts easy and can be worked just as easy as the Blue/Pink foam board so that it was no problem in making the right-of-way flat for the track to go through!

This should work with a stud wall as well.  Just use the low expanding foam so there will not be a lot of expansion to put pressure on the drywall and cause any bulging of the drywall.

BOB H - Clarion, PA

[CSXDixieLine]

Here is a page from the construction progress on the N-scale SPSF Owens Valley Sub. The builder has done exactly what has been described above as the "box" technique (lots of good pictures):

http://www.owensvalleysub.com/june2007.html

Jamie

[Shreve Rail]

Thank you, Pasadena Sub, for the Owens Valley pictures!

[CSXDixieLine]

Thank you, Pasadena Sub, for the Owens Valley pictures!

You are most welcome...looked like that was pretty close to what was described above. Jamie