A Swing Bridge instead of a Duck Under
Now - Electrical --- Here you have an option. If you are confident that you will never run a train over the bridge When It Is OPEN then just attach the wires from the bridge rails to your lead track on the hinge side. Make sure you attach the right wire to the correct rails Do this with the bridge "Open all the way" so you will have enough wire to open the bridge.

Also you may (As I had to) have to attach a lead weight to the wires, so they would not bind in between the 2 --- 2 X 4's. I had to put a loop and send the wire through it, so they would nit get caught by closing the bridge.

If you want to add a safety switch (pressure switch) you will have to insulate both ends of the "power side" of the lead tracks about 2 feet on either side of the bridge.

The circuit is simple. Follow the diagram below.
The green is the power feed wire, either DCC or DC throttle. This wire attaches to the Common terminal of the pressure switch. The red wire goes from the Normally Open terminal of the pressure switch to the rails as shown by the red wires. this effectively makes the 2 foot leads & the bridge a separate block. The Blue wire basically assures that the bridge will have power to the "common" rail.

The picture below, shows the wiring hanging down, through the lead weight. Remember, the wiring will have to be routed around the layout to the switch and the "other" end of the track across the bridge.

The only way to avoid this is to somehow attach the momentary switch to the hinge side of the bridge instead of next to the throw bolt.

Well - that's it - hope you had fun reading this - now go build one!!! If you have any questions - PM or e-mail me & post pics of your progress
~~ Mikey KB3VBR (Admin)
~~ NARA Member # 75    
~~ Baldwin Eddystone Unofficial Website

~~ I wonder what that would look like in 1:20.3???

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