Yesterday, Saturday June 3, I got up out of bed at 7 am and by 9 am the patio thermometer in the sun showed 104 degrees. So I waited until about 1 pm and went out into the garage where the N-scale layout is to check on the expansion. WOW, I have gaps cut in most staight sections just for expansion, and they were almost complettely closed. I used a cutting disc so the gaps are substantial. I glued my track down and thought with the gaps I would be ok, but one turnout a the throught of the yard pushed back a bit caused a small peice of rail to shift sideways.[censored]. I hope that all that will be caused from this problem as there was much time spent making this puppy run good.
This is just an FYI post. We have talked about this a few months ago, but now that the heat is settling in I thought I could record some results.
I will be adding more gaps, as I guess the heat extremes here will keep me on my toes.
There are benefits to living in the Great White North [8D]
Ya, shrinkage and you probably get your MR two weeks after the states[(-D]
This has been discussed previously, several times, on this forum. The problem is not with track expansion, it is your wood benchwork expanding and contracting with changes in temperature and humidity.
We conducted experiments with Atlas code 100 HO scale flex track to determine how much expansion and contraction there is in nickel silver rail before our large club layout was built in a building with no climate control. Two 3-foot long pieces of Atlas flex track were soldered together and placed outdoors in full sunlight on a day in July when the air temperature was over 100 degrees. The temperature of the metal rail was measured at close to 140 degrees, and the length of both rails was carefully measured. The track was then placed into a chest freezer overnight and the rails were again measured at 0 degrees. There was less than 1/64th inch contraction between the two temperature extremes in 6 feet of rail.
Wood expands and contracts much more than this with changes in the weather.
And you see that as a problem?
Bob Boudreau
cacole;
Just curious but was the measuring tape or what ever you used immune to the same expansion and/or contraction. Otherwise, if a steel tape for example, was used it was also expanding or contracting giving false readings.
Just a thought I had about what your club did to confirm the expansion/contraction of the rail.
You definately experience some extremes in Riverside. Your benchwork is about as dry(shrunk) as it going to be, unless it has just recently been built. Have you ever considered a thermostatically controlled exhuast fan, located in the loft or gable of the garage? Even if you use A/C periodically, the fan will remove a considerable amount of heat when not in use. I had used one when living in Diamond Bar/Walnut to make the garage usable for a workshop. I install these even here (Ma) in a more temperate climate, and they work wonders in the house or garage attic.
Since you need not worry about humidity, once you have gapped the rails in the heat of summer, you should not have any trouble in the future.
Bob K.
Wanna bet? Most Canadians get theirs before you guys in the States. I’m not going to touch that shrinkage comment, lol.[;)]
As mentioned, humidity will expand wood way more than heat will expand anything. Pine is as bad as any. I finally sprung for a window air conditioner for my garage, as much for humidity as temp. In Minnesota we deal with temps from 105 above to 40 below, all with Flordia type humidity. I had four layouts before climate control, but this sure is easier.
Never had a problem with expansion or contraction as my layout have been inside. lol
However, I did have a ceiling fall on own.
Now that REALLY makes a major affect on a layout.
Strange weather we’re having, it’s raining ceiling fans.
My layout is indoors in a controlled environment. The temp is a constant 70 degrees and the humidity is a constant 60%. I live in west central Louisiana, if that tells you anything. You can get soaked just by stepping outside on a dry day.
WOOD expands as it absorbs moisture.
HOMOSOTE being cardboard, absorbs even more moisture.
RAIL - being a metal - expands from heat
The PROBLEM is they expand at different rates for different reasons, and
SOLDERING rail joiners exacerbates the problem.
Looks like you might want to consider installing an AC unit in the garage. I installed a window unit in our garage of our previous house two years ago because the laundry was out there too and the CFO wanted to not have to sweat when doing the wash. The unit was also able to heat too in the winter.
Does anyone have any experience with foam-based layouts in these extremes? I know that 2-inch insulation foam, which everyone carries here in the frosty Northeast, is kind of rare in states where triple-digit temperatures are common. Still, some of you guys make a point of using it. I would imagine that it would be much more immune to expansion and contraction than plywood.
MisterBeasley I used 2 inch foam once and never had any expansion problems at all.
As a note here, I have and still will soldered up to 3 - 3foot rails together and had no problems with expansion etc. My place was not particularly stable either, temp wise.
I knew a group that went up to 25 feet but that was in a special room.
Foam is very stable having used it in construction and such. It can not expand and contract, or at least not noticeably.
I think a little. I have a entire layout base is made of 2" white foam. I did notice though, that as it got colder, some of the gaps between the foam grew a little. Where there was no seperation, I would have 1/16-3/32 gaps in some spots. But my bench work is far from solid. In fact, it is pretty weak. (I built it quick). I would assume that if you had your foam stuffed and snugged in with the wood, I dont think it would go anywhere. But then, what ever issues you did devolope, would come from the wood.
I’ve been lucky so far not to have a major problem. I live in Georgia so heat and high humidity are a given (most of the time). I visited an N scale layout recently, in an unairconditioned building, and the track and roadbed were laid directly on the plywood base. Once section of straight track is now a slight S curve due to the heat and humidity. Those guys are really having a time with it.
Jarrell
On a related thought, it would have been useful to have measured all gaps on the railroad with a micrometer to see if any had changed their dimensions, AND if their boundaries had shifted in relation to where they were positioned at an original measurement. It is one thing to measure one item in relation to what surrounds it, but the whole will have been affected to the same extent…one needs an external referent from which to determine what, if any, changes have taken place.