Editor’s Note: This is an article submitted by one of our boatbuilders, Doug Wade, whose Glen-L Tubby Tug photo gallery can be found here.
As I promised here is my description of how I put a fire monitor on my Tubby Tug. This is my “thank you” for the smiles your Glen-L Newsletter gives me.
How I installed a fire monitor on my Tubby Tug, by Doug Wade, Toronto, Canada:
With my experience as a retired science teacher I think it will be most useful if I write the description as a set of instructions in a manner similar to a science lab exercise.
Before the description a short side comment…I am astonished how often and for how long my grandkids want to ride in this little boat. It puts a smile on every face that sees it and the fire monitor truly is the icing on the cake.
Small 12 volt high pressure pony pump (often used by farmers to pump pesticides, hose threads on pump)
½ inch through hull fitting.
½ inch clear nylon reinforced plastic tubing (appx. 8 feet)
2 male ½ inch hose barbs
4 hose clamps
silicone bedding compound for through hull
4 inch to 2 inch black sewer pipe adapter
2 inch to ¾ threaded hole black sewer pipe adapter
shower goose neck
½ inch 24 degree cast iron elbow
teflon plumbers tape
single piece brass plumbing adapter ¾ inch hose thread to male ¾ inch thread and miracle of miracles ½ inch female internal thread
two 45 degree garden hose strain relief (one end male one end female)
1 inch ½ inch copper pipe
fat O ring to fit over ½ inch copper pipe
brass garden hose nozzle
red electrical tape
small sealed lead acid battery (6 to 10 amp hour) such as used in a kids stand up scooter
1.6 watt solar panel
12 volt push button switch, assorted wire and connectors
6 inches of 4 X 4
8 inch plastic boating access port
Mounting the Fire Monitor Post
- Round the edges of the 4 X 4 until the sewer pipe adapter will slide over it easily
- Cut the bottom at an angle so that it will sit vertically on the foredeck just forward of the pilot house wall
- Cut the top of the 4 X 4 so that the sewer pipe will be about ½ inch above the deck when the 4 X 4 is glued to the deck
- Bore a 1 inch hole vertically through the 4 X 4
- Epoxy this fire monitor mounting post on the centre line of the foredeck with the centre of the post 3 ¼ inches forward of the pilot house wall
- Continue the 1 inch hole in the post through the foredeck
- The post looks good if painted black
Mounting the Pump
- Install a ½ inch through hull fitting inside the port seat in the forward centreline corner.
- Connect a long loop of plastic pipe from the through hull to a hose barb and then to a 45 degree strain relief. The idea of the long circular loop and 45 degree fitting is to create as large a radius as possible in the hose.
- To gain access to the seat for wiring and plumbing glue a ½ inch thick, 1 ½ inch diameter wooden washer to the top of the seat in the stern corner under the side deck and then drill a 1 inch hole through the washer. This arrangement will stop water from flowing into the seat, will keep the interior of the seat compartment dry and will allow easy installation of battery wiring and fire monitor plumbing.
- Thread the monitor hose through the seat top access hole and into the seat compartment
- Fasten a female hose barb to the hose
- Connect positive and negative wires to the battery
- Slip the battery through the 8 inch plastic access port in the seat side
- Slip the pump into the seat
- Connect the suction and output hoses to the hose fittings on the pump
- It is desirable to cobble some sort of mounting system for the pump. Below is a photo of an old window catch used as an easy-to-use mounting.
Building the Monitor
The key to the monitor is the brass fitting and the 1 inch copper pipe. To give an overview the water flow is as follows: through hull, suction hose, 45 degree hose strain relief, pump, output hose, hose barb, 45 degree elbow, short end of shower gooseneck, up through the centre of the fire monitor post, brass fitting, 1 inch copper pipe, 45 degree strain relief, garden nozzle.
- Solder the 1 inch copper pipe into the hose barb end of the brass fitting and allow about ½ inch to protrude. The junction between the fitting and the pipe must be smooth and should be dressed with a fine file if it is not.
- Weld the 2 inch to ¾ inch black sewer pipe adapter into the 4 inch to 2 inch adapter and then thread the brass fitting into the ¾ inch adapter
- Put plumbers grease on an O ring and place it over the protruding ½ inch copper pipe
- The 45 degree strain relief will fit over the ½ inch copper pipe and onto the brass hose barb. This arrangement will allow the nozzle to be pointed to the left and right and the O ring is the seal that prevent leaks.
- Connect the Brass garden hose nozzle
- Lightly sand all the black plastic and paint red
- Adjust the nut on the bottom of the strain relief so that the nozzle turns easily and then wrap the nut and the top of the brass fitting with the red electrical tape to hold the nut in place
- Place the complete fire monitor on the monitor post
- From underneath the deck thread the long end of the shower goose neck into the bottom of the brass fitting
- Place 45 degree elbow and hose barb on the bottom of the goose neck
- Run hose from the monitor to the pump
It is best to control the pump with a relay in the seat compartment with the battery and pump but with the short wire runs involved the pump can be controlled directly with a high current push button or momentary toggle switch on the dash. After two summers of use I have found that a 1.6 watt solar panel on the roof is adequate to keep the battery topped up and the pump running. Little kids will find the switches hard to operate and will lean back and use their feet therefore use robust switches. For the benefit of wiring novices:
- Connect black negative battery to black negative pump and to black negative solar panel wire if used
- Run red positive battery to inline fuse and then run a red wire to the pilothouse dash and connect to the switch
- Run red wire from the switch back to the red wire on the pump
- Run red wire from the solar panel to the red positive terminal on the battery
By roughly planning all of this before the build was started I was able to easily drill the hole in the seat top and route wire chases in the pilot house front post and top beam to keep everything hidden and tidy and of course if this much work has been done the addition of running lights is very simple.