I have an American Flyer layout with 17 switches powered by a separate 18 V transformer. The output of the transformer is 18 V however, the output at the switches when thrown is only 8-9 V. I have tripled-checked the wiring and all seems to be in order. Also, I a different transformer with the same results. Does anyone have feedback for what can be the cause of the voltage drop?
You may want to post this in Classic Toy Trains. This is Classic Trains, which covers real railroads of the past.
It is a common and simple problem with a simple fix. Inside the turnout there are brass contacts that connect the straight or divergent frog rails when the turnout is thrown. There are also similar sliding brass contacts that enable the “reg” and “2-train” settings on the slide switch. Over six decades these brass contacts have oxidized and are causing the voltage drop. I have some Gilbert turnouts where the oxidation is so bad there is no continuity at all.
The fix is to remove the screws under the turnout and take off the bottom plates. These contacts and wiring are visible. Clean all the brass contacts with a 400 grit sandpaper. When they are a clean, bright brass, apply a small amount of No-Ox or similar so they do not oxidize in the future. A picture of what I use is below. It can be purchased at the local hardware store.
While under the turnout, lubricate the wedge end sliding slug that moves the points so they snap freely. Put the bottom plates back on. Use the 400 grit paper to clean the track pins and apply a very small amout of the No-Ox on the track pins. There will be no more voltage drop.
If you are using a 690 track clip for power, use the 400 grit paper plus the No-Ox on the rail flanges where the 690 makes contact. I have found there can be as much as a 1.5V drop at the 690 attachment point.
Thanks a million Tom for your feedback. It’s refreshing there are people like you willing to share their knowledge, time and energy with others. I will apply your tips this week and look forward to the results. Thanks again.
Let us know if it works or if you have some detailed questions.