Foam and tunnels.

[HarryHotspur]

I do use it for some sidings, but not for the mainline where I want more strength and rigidity.  

Hmmm.  Interesting notion.  I've never had trouble with it being too flexible or soft -- although keep in mind that I'm using it as subroadbed. Mine is covered with plastercloth and hydrocal, with foam roadbed on top of that.  It's glued on with adhesive caulk, and I never have trouble with stuff moving.  Stuff I don't want to move, that is.

True enough. As a first year newbie, I listened to the foam hype and tried a foam subroadbed for my yard and just could not deal with the issues.  Mounting turnout motors, attaching and securing wiring, running wires through the foam were just some of the major challenges.  Certainly there are work arounds and methods, straws for wires, fancy techniques to mount torti, etc. Just too much bother for a roadbed whose only advantage over 3/4 plywood is the weight. 

Just my 2 cents

Joe Daddy 

 

Light weight isn't the only advantage of foam. It's much easier to cut and otherwise work with, especially for those without much in the way of power tools. Installing wiring is slightly easier - just punch a hole instead of drilling it. I don't use Tortoises, but Peco motors are much easier to mount. Etc.

[joe-daddy]

Well, we've made the circle, foam is once again easier.  I'll step off at this station.

Peace to those who've contributed.

Joe Daddy 

 

[HarryHotspur]

Joe, the point is "to each his own." There is no one best solution for everyone. I only know what worked best for me.

[trainnut57]

Most of my tunnels are against walls where viewers do not tread but operators do, thus the entire sides are open for easy access in case of emergencies. However, (and I hope this isn't a jinx) prior to building the tunnels, I make sure my track is true by running lots of equipment over it for a significant time to see if there will be any trouble spots. So far after covering the tunnel, I have had only one mishap on a 25" radius with an 85' car. My method is using foam insulation board, 2 to 3 inches thick for the basic structure, then placing chunks of the stuff along the top in a halter skelter way, if I am constructing a mountain tunnel, and covering it with plaster cloth. If necessary I "fill in the blanks" with plastic bags and masking tape to make the contours appear as natural as possible.

 Hope this helps.

[der5997]

I guess I have a combo of access methods for the stacked foam tunnels on my layout.  Removable facia access where that's handiest,

and lift out hatches where it's not.

 

some of those hatches BTW are to get at some electronics as well, so are not necessarily a "tunnel only" feature. All my tunnels have hidden passing sidings, so I need to be able to get at the turnouts / motors for maintenance.

Picking up on Don Z's observation

I will side with you regarding your dislike for stacking foam. I don't like that method because no matter how hard the users try, the horizontal seams in the layers of foam are visible and therefore distracting to the overall appearance of the scenery.

, I agree in part, but I used that underlying characteristic to advantage (IMHO) by overlaying rock castings to follow the strata.

Most of the ground cover in these photos hasn't yet been stained, and so is the natural colour of the sawdust / white glue mix which is my basic approach for this layout.

The thing I'd do over if I used this method again, is to NOT use the foam board as the track sub roadbed without plywood support.  I didn't know, and the resultant noise from the trains is a real drag.

If you were wondering what the tunnel like blue card structure was inside one of those hatches, it leads up to a light box showing a scene as if the track goes straight through from the tunnel mouth (instead of curving to the left along the back wall and behind the long rock face)