Why do my trains slow down at a particular place on the layout?

It can be annoying and a little baffling when model trains slow down, seemingly without reason, at a particular spot on a layout. There are several reasons why this can happen, here are a few of the most common causes and solutions.

1. Check that your rail joiners are in good order. If one has failed on an end to end layout, your trains will simply stop, however, on a continuous run layout, power will still be delivered to the whole layout, but your trains will slow down significantly as they cross from tracks with a good power feed, to ones where power has had to come the long way round the layout. To rectify the problem, you can either replace the rail joiners in the affected area or run a separate power feed from your controller to the troublesome section of track.

2. Check your rails are clean. It sounds simple but, the most common cause of slow or unreliable running is dirty tracks or wheels, so make sure they are squeaky clean.

3. Check all wheels spin freely. A stiff wheel may not on its own be enough to cause problems, but most problems are amplified when sharp curves are involved. If your train is slowing just after a curve, check if all of the wheels are running freely. Sometimes the axles require a spot of oil but sometimes they have simply become displaced from their housing, so it's always worth a quick check.

4. Consider if your consist is too long. Long trains require a lot more power and traction to get them around a sharp curve. Try the same locomotive with a shorter consist to ascertain what the limitations of your layout are.

5. Consider if you are experiencing voltage drop. The further from your controller the power has to travel, the less oomph it has when it gets there. If your trains are slowing at the furthest point from the controller, voltage drop is likely the cause. You can rectify this be installing multiple power feeds coming from your controller and joining them to your track at regular intervals around the layout.

It is not often realised that railway layouts have limitations. By ensuring that tracks are regularly cleaned, rail joiners alone are not used to ensure power delivery to the whole of the layout, wheels are kept clean and free-running and expectations for long consists are kept realistic, your trains will stand a fighting chance of running reliably. Some modellers even enjoy the servicing, maintenance and route availability aspects of modelling as it makes their railways a little more like the real thing, so it doesn't have to be a chore!