Running any Trains but especially big Steam trains like the Hornby P2 Cock o' the North (a 2-8-2 layout with a 2 wheel front bogie) is a challenge with points/turn-outs on any track. I had major problems with my P2 where it would de-rail on points on my Bachmann EZ-track layout. The following comments are based on what I learnt when I solved my de-rail problems.
How to fix de-railing trains on Bachmann ez-track points
One solution that I have not seen talked about anywhere else online is to be careful where you put the points. Do not put a point/turn-out immediately after a curve. Instead always have at least a 9-inch straight before the point/turn-out which helps straighten the front bogie of every train before it hits the points and the frog of the points.
See in the pic above. If a train runs left to right it will have problems because the points are too near to the curve. The train coming off the curve will probably de-rail. However if a train runs right to left it will be fine because the train hits the points coming off a straight. It does not matter which way round the points are if they are too close to a curve you will have de-rail problems.
Other factors can cause de-rails so if re-positioning does not cure your de-rails then run your fingers along the tracks and feel for any lumps/bumps/bends etc in the tracks. These should be filed out or flattened as these can cause de-rails. If you can feel a lump then its big enough to be a problem so remove it.
Another thing to do is to check that the front of the moving part of the points is fitting flush to the track. If its not flush then again filing it or filing the track is required to make the de-rails stop.
Another possible cause of de-rails is sticky wheels. If the wheels of the engine or the coaches don't spin freely with a finger spin then they need attention. You need to oil the wheel axles at regular intervals to keep them spinning with the least resistance.
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