The Wood Elevator Top Switch can be placed on top of the Wood Elevator Track to create a functional elevator. But has to be next to or on a foundation for it to be in range for foundation support (unless the first track is on a foundation, then you don't have to).
After placing down Elevator Tracks, the switch has to be placed on the top of the highest elevator track. If any Elevator Platform is attached to the tracks and you are standing in front of the Top Switch, pressing E repeatedly will slowly lift the platform up.
The Wood Elevator Top Switch can be locked or made available for public use via the radial menu.
Quick tutorial on how to place and use the wood elevator.