Weather problems and "welded rail" Q:

Discussion in 'N / Z Scale Model Trains' started by WM-N-fan, Feb 26, 2003.

  1. WM-N-fan

    WM-N-fan Member

    I recently welded (soldered) the first track of my main. The rail is flex track. I was soon operating 30-50 car trains without diffuculty. I stopped a 30 car grain extra after 30 perfect laps. Then a week later I started the train up. Over the mainstreet overpass on a horseshoe curve, the whole train fell outward with even cars off the table! I soon realized that the track had shifted off the roadbed and was on a graded angle. I rerailed the train and hoped that this was a fluke but it happened again. Is the story that n-scale rail shifts true? I'm now left with the options on regrading my main through 4 feet, using more nail to "retack" the main or just tearing it up and adding new jointed rails like snap track or flextrack, that isn't soldered. Answers and ideas please............
  2. Tyson Rayles

    Tyson Rayles Active Member

    N-Scale rail when properly installed won't shift anymore or less than any other scale. What kind of temperature highs and lows did you have in the room during that week, how was the track held down and to what? Can you post a picture of the affected area?
  3. 60103

    60103 Pooh Bah

    Frost kinks

    How much rail was continuous, and over how much of the curve? You may be able to fix it by cutting the rail and adding a rail joiner.
    It's not just temperature; humidity does interesting things to your benchwork, and, of course, the humidity went down when the temperature sank.
  4. Vic

    Vic Active Member

    Most likely the problem is not in the track itself but its resulting from expansion and/or contraction in the bench work due to changes in temperture and humidity. If you can try to stabilize the the temperature and humidity of the aera where your layout is located. Actually humidity is the big factor with wood as it expands with high humidity and shrinks with low humidity. Around 40% is ideal for personal comfort and keeping the layout benchwork stable.
  5. Paul Onsen

    Paul Onsen New Member

    This isn't going to help your immediate problem, and I pose this idea more for the general forum, but your possible temp/humidity problems got me thinking.

    Group: before I begin building my N-gauge "empire on a door", I wonder if this is worth doing ... I plan to use a layer or three of pink foam insulation to allow me options to create mountain passes, etc. Wondering if, rather than gluing the first layer down onto the door, I might be better just mechanically restraining it from shifting off the door by using wood trim all around secured to the door but not the foam ... with also some (removable) restraint against uplift in case I need to tip the layout sideways during transportation.

    The foam presumably is not subject to variations in size due to temp or humidity, so perhaps track problems due to support warpage would be prevented?

    Just a thought ....

  6. Clerk

    Clerk Active Member

    I take my dremmel with a cut off wheel and making sure the tracks are secured to the ties, make a cut through the rail. This gives it a small gap that should compensate for the stretching and shrinking of the rail.

    But if it is the bench that is warping, that is another problem except if you have styrafoam as the top layer than it is not the bench.
  7. WM-N-fan

    WM-N-fan Member

    Well, the track was ballasted and on AMI roadbed, which was on white foam, with a layer of insulation foam under that and a 3 inch thick oak atble under that. The track was nailed in and even had railjoiners. The curve was about 16.5 inch radius. I will take some pictures. There were two former joints on the curve. If the curve is 180' the joints are at about 37' and 110'.
    Temperature wise the room, being the basement has maintained about 65' temperature almost all year with as large as 5 degree changes. I will post more this evening.
  8. Tyson Rayles

    Tyson Rayles Active Member

    I use AMI also. If you don't use a white glue/water mix (50/50) to hold the ballast AND the track to the AMI (and if temps are less than 75 degrees this is really true) the track WILL come lose and shift. Yes I know AMI says it won't but it will. If you relay the track the way you had it than do that and after 24 hours REMOVE any nails (they tend to keep everything from shifting together as a unit with any temp or humidity changes, therefore causing no problems) you should be O.K. At least that has been my 6 years of experience with the product. :)
  9. ezdays

    ezdays Out AZ way

    Well, I don't know too much about trains yet, but I think I know a bit about construction, so... Unless you are using a solid wood door, expansion is not a problem. A hollow-core door is laminated with plywood or a composit and should not expand. additionally, if the base layer is all plywood, it should be rigid as well. Wood expands against the grain, not with it and plywood alternates the grain at each layer. If it got soaked it might exapand slightly, but more likely it would grow thicker not longer. Any changes due to humidity would be negligable, and certainly not be able to cause the foam layers to move. Solid wood benchwork could be a problem. Me, I'm using a composit material for my first bench and it shouldn't be a problem.

    Your best bet would be to paint both sides and the edges of the door or plywood or any raw wood if dampness is a concern.

    Now I can see where track would expand with temperature changes. The advice someone gave me in another thread of not soldering every rail joint sounds like a practical way to go.


Share This Page