Train derailments are a common problem for model railroaders - and one of the most annoying. It's one thing to have a derailment during design and construction of your railroad. Even the occasional derailment from excessive speed or other unforseeable causes is understandable. When it happens at the same place on a regular basis, however, there is probably something specific causing it.
If you're seeing regular derailments on your layout, the first step is to determine where it's happening and whether it happens to all your cars or just specific cars and locomotives.
If the derailment is happening on a curve, don't automatically assume the design of the curve is at fault. The train wheels could be jumping on the head of a nail, for example, that causes it to rock then derail.
It could also be a problem with a particular wheel on the train or another part of the car. Troubleshoot the problem with just a locomotive first, then add specific cars to see one in particular causes the problem.
Couplers are another possible cause. If they're too low to clear switch points or other parts of the track, this can knock the train off the track. In this case the solution is straightforward - adjusting the coupler with plastic shims or washers is usually enough to solve the problem.
Trucks can also cause problems, although it is pretty rare. If this is the case, it's usually the screw holding the truck in place - it may be too tight and need to be backed off a little.
Uneven surface on your layout can cause bumps or rises in your track, leading to derailments, as can rails that aren't properly secured. You sometimes run into this problem where two tables connect. They need to be level and securely connected to one another to prevent problems.
Switches are another common problem spot with the rails themselves. If you think this may be the case, make sure that the frog and guide rails are clean and work smoothly. Even a little bit of dirt can cause problems.
When testing a switch, it can help to run a spare truck across the switch by hand to see if you can feel any instability.
email