My goal when designing the controls for Pembroke has been to simulate the actions of real railroaders, but smaller and lighter. Real railroading is heavy, dangerous work, after all!
When it comes to the Pembroke water tower, this means there is, of course, no button. Almost nothing had a button in 1905, except for the fly of your pants. Even today, when a fireman encounters one of the few remaining operating water towers, it is a two step process. First, they must pull on a chain to lower the spout and line it up with the hatch in the tender. Often, they’ll hold it there with their foot while they pull on a rope that passes over the rim of the tank and connects to a valve at the bottom of the tank, releasing the flow of water.
On my water tank, the operator lowers the spout by pulling on a piece of chain that is connected to a fishing line. The fishing line passes beneath a plunger that is connected in turn to the spout by a thread that passes over the lip of the tank, representing the valve rope on the real tank. I considered motorizing this linkage briefly, but decided not to because I wanted the operator’s muscles to be connected to the spout. If the operator moves the chain slowly, the spout should move slowly.
To release the flow of water, the operator pulls a rope that is connected to a switch. This switch starts the sound of water and moves the slider on the linear actuator down. A second plunger rests on the slider and is connected via a magnet to the ball float. When the operator releases the rope, the switch opens and the sound of water stops. The linear actuator then slowly moves slider back to the end of its travel.
The business end of the mechanism. The brass bar supported by the fishing line is connected to the end of the spout; lowering the bar pulls the spout up. The second plunger is a piece of steel rod, barely visible behind the limit switch.https://youtu.be/6Qyh_IPW45E?si=OxIWFZCj4nvuWUL1
https://pembroke87.ca/2024/09/24/water-tower-mechanism-in-action/