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Fire Monitors Part 1

I want to have working fire monitors on the boat, so decided to make them in brass. I also want them to swivel. To give the right appearance, the water needs to pass through the vertical support column into the body of the monitor. I don't want a separate tube from the body of the monitor going through the cabin roof as it would not look accurate, and will likely restrict the rotation of the monitor. The body of the monitor is made from a short length of 6mm brass tube with two turned end caps. The front cap, the nozzle, was turned and filed to a suitable shape on the lathe. The inside is drilled out as much as I dared to reduce the weight. The nozzle outlet was initially drilled 0.6mm dia. During initial trials with the pump connected this was opened up to 0.85mm dia. to give an increased water flow without having any significant effect on the throw of the jet. The rear end cap is also drilled out internally to reduce the weight. Two 3mm holes are drilled at 45 degrees at the rear of the cap to attach the curved copper pipes which will carry water from the vertical support column. Bending the 3mm copper tube to shape was tricky, it is a tight bend but I managed it without it collapsing too much. The tubes will need a bit of cleaning up before painting. The connection to the vertical column is formed as a T piece from two short pieced of brass tube. These were soldered together using for strength. Two small turned flanges connect the copper tubes to this T piece. The handles were cut from brass sheet with a length of 1.5mm brass rod as the cross piece. All the parts were soft soldered together. The completed monitor body was connected to the pump and tried out. One of the soldered joints was leaking and had to be remade. Having drilled out the nozzle to 0.85mm dia. the resulting water jet looks effective with a throw of around 2-3 feet.

5 years ago by Graham93