Gapping For Cold Weather

Tom,

If I may make a suggestion-heat the garage.  Insulate if it's not.  You'll enjoy your layout much more. Money well spent.

 

I've had layouts in unheated/non-insulated attics and it's no fun.  Cold in the winter and miserably hot in the summer.  One summer as a kid I couldn't even work in the attic-it was over 120 degs.

 

FWIW, my well insulated shop is 25X35 and in the winter it stays well above freezing-typically 40 degs or better even when it was -10 outside.  Never gets below freezing, and that's without the heater turned on at all!

 

I think your effort to have heat will pay off in big rewards and make your experience much more enjoyable.  It just makes everything so much easier when you're comfortable-even simple tasks.

Hi 86T______:

 

The garage is unheated.  The train/workshop is heated via pellet stove.  I won't be heating it the entire winter, only when I use it.  The workshop is insulated and built off the ground on piers so the floor will be warm after 15 minutes running the pellet stove.

 

 

At -20 t0 -30 degrees, there is no amount of insulation that will keep the room warm without a stove.  My garage is not attached to my home.  With the stove running on idle, I can keep it a working comfortable 63 degrees.

 

So, if I'm gone, the stove will be off.  Maybe it will be an hour or 3 days until I use it again.  In the meantime, I have exposed my layout to some significant swings between sub freezing and 63 degrees.  I live in upstate NY.  That's not just outside the city.  I'm up in the Adirondak mountain area.  Our snow has been gone for only about 1 week.

 

Thanks...   Tom

Change in length is directly proportional to change in temperature.

 

Δ length = initial length X α X Δ temperature.

 

For steel, the coefficient of thermal expansion (alpha) is .0000067 in/in (F).

 

Let’s say you have 100 feet (1200 inches) of track in a loop and your temperature will range from -20 degrees F to 100 degrees F.  If you installed it when it was -20 degrees it would grow to 1200.9648 inches

 

Δ length = 1200 inches X .0000067 in/in (F) X 120 degrees F = .9648 inches

 

So if that loop is made with Gargraves flex track sections which are 37 inches long, you would use about 32 sections and would need 1/32 inch gap between each section IF you install it when its -20 degrees.  If you install when the temperature is tolerable, it would shrink when it gets cold and you wouldn’t need a gap when you install it.

 

Bottom line - I wouldn’t worry about change in track length due to temperature changes.

 

Bob

Just read your original post again.  The 148 ME flextrack is nickel silver which I suspect is mostly nickel.  The coefficient of expansion for nickel is .0000072 so not much different than steel.

Without all the science, I'll agree.  Install it when it's warm, and you shouldn't have a problem with the cold as far as track goes. 

I think another interesting consideration would be not the expansion of the rail, but expansion of the surface the track is attached to. 

For long straight runs in a non climate controller area, humidity can really change the layout dimensions.  Could be especially problematic for drop in bridges.

Mike