Humidity and temperature changes

[JBSteamer]

The only place I have to build a layout is in my workshop on the back of my airplane hangar. It's heated but I turn the heat down to 60 when I'm not out there and with the increase in propane costs maybe lower this winter ( I'm located in Michigan).

My layout size will be approximately 5X12 in HO and the table is constructed of heavy 3" angle iron. I plan to use a kind of open grid of 1x4 running across the table. I'm planning a continuous running loop around the full size of the table with the back part of the loop hidden by a natural view block. The hidden track will be accessable from below as the area behind the view block will be open.

Here's the question . . . If I use two inch foam as a base, covering the front part and a strip along the back to lay that track on, can I avoid the problem of hummidity and temperature changes? I plan to use cork road bed and Atlas code 100 flex track. This is going to be a freelanced shortline in the early 50s with steam and small diesel with 40 foot rolling stock. Your opinions are appreciated.

Thanks.
Jim

[gandydancer19]

Here's the question . . . If I use two inch foam as a base, covering the front part and a strip along the back to lay that track on, can I avoid the problem of hummidity and temperature changes?

You may eliminate most of it, but I wouldn't count on it altogether.

What I would do is lay the track as you normally would. About every six feet, I would make sure that you have a gap of about 1/16 inch between two track sections. Because I favor soldering rail joiners, I would solder all the rail joiners that occur between each of the 1/16th inch gaps. Don't solder the joiners at the 1/16 gaps so they can allow for some temperature changes. Chances are that you won't get your layout completed before next winter, so if something does happen, you should be able to correct it without messing up the scenery.

[cacole]

Wood expands and contracts with changes in humidity and temperature much more than metal or foam, and is usually the cause of track buckling.  My main concern with foam alone, other than the possibility of sagging over time if it is not adequately supported, is the way it resonates the sound of trains running on the track.  I would paint or seal the 1x4 crossmembers to prevent warpage, but other than that you should have no problems with humidity or temperature changes.

We have a 20 x 40 foot HO scale layout in a building with no central heating or air conditioning here in the high Arizona desert where wintertime temperatures drop below freezing and summertime temperatures sometimes top 100.  This layout has a 2x4 framework and is built on hollow-core doors topped with one inch of sound board glued in place with latex caulking.  Humidity ranges from 10 percent to 70 or 80 percent, and we have had no problems from these extremes.

[jeffrey-wimberly]

Gandydancer, you nailed it right on the head. Down here in Louisiana temp and humidity changes are something else. I cut gaps about every six feet even though my track is laid on styrofoam on top of plywood. The only time I had a big expansion problem was right after Rita came through.

[loathar]

If you can keep the hanger between 50 and 90 degrees, I doubt you'll have much trouble. Especially with metal and foam. The wood is what swells and shrinks. Just use the rail gaps as mentioned above. My layout was fine the first year. Then the second year, all these track kinks showed up when it got hot. I fixed those and added rail gaps last summer and so far it's been fine this year. My building ranges from 30-115 degrees and I used all wood for for my bench work and table top.
Atlas code 100 is pretty bullet proof.