Portable Air Cooler, Made Out of an Old Metal Oil Can.

Being from one of the hottest states in India sometimes frustrates me a little. I like spending time on my terrace but the weather drips me down in sweat within hours, which made me decide to find, temporary, if not permanent, a solution to this shirt-drenching problem. One evening on my terrace, I came across this old metal can, and the scientific cat inside me thought of an idea. Becoming unemployed recently gave me a little time to work on this small project, and to spend the rest of my free time on the terrace with my cooler. :D

The 'Meta-Cooler XS', as I like to call it, is probably one of my best creations, which cost me almost nothing. It is effective, portable, eco-friendly, energy saving, easy to make and quite stylish to be honest, though feel free to design it your way.

Step 1: Materials Required.

Most of the following things could be available either as scrap at your home, or at your nearest hardware store:

Old metal oil can ( approx 13"x9"x9")
Two 12V motors.
A small fan blade. (approx 5.5" diameter)
5x40mm bolts and nuts.
Long square tube (8"x1/2")
A small switch.
A 12V female connector for the power supply.
Blade for the water pump.
1 mt plastic pipe for water circulation.
Metal wire net from trash.
Dry grass.
Bottle caps for the water pump.
Insulin syringe tube.
Glue gun.
Electrical wires.

Step 2: Giving Shape to the Can.

The first step in making the cooler would be cutting in the can and giving it the shape it needs (refer to images).

Using a marker, mark 3 equal squares (approx 6.5"x6.5") on the 3 sides of the can, and a circle (approx 6" diameter) on the 4th side. With the help of a cutting knife or a grinder, cut the can from the markings to give it a cooler-like shape. The circle-side would be used to attach the fan, while the rest three would be used as windows covered with dry grass. Bend the edges of the square, as marked, inside so as to fit in the dry grass. ( See image)

Step 3: Making Water Pump.

Next, we'll make the water pump, which will help in circulating the water in the cooler. To make the pump, you'll need a 12v motor. I am using a plastic tube to cover it so that it will be waterproof. Then take a plastic cap of the correct size to fit the blades in for the main section of the pump. I have used a small fitting to fit the blade to the motor shaft. After that, I have covered it with another cap and fix a syringe tube as an outlet and hold them together with hot glue. Next, take a plastic tube (approx 1m) and make holes in it. This will allow the dry grass to get wet ;)

Step 4: Making a Base for the Main Motor.

Use a 1/2" square metal pipe and drill holes on both the ends to connect it with the main body. After that, you need to measure the center of the pipe and drill 2 holes to fit the motor. Using a metal strip, curve it around the motor to fix it permanently.

Step 5: Cutting Metal Net for the Window.

Next, we'll make dry grass sandwiches (not edible). Cut the metal net according to the size of the window and spread dry grass on it. Make a sandwich with dry grass in between. Check if they fit properly on the side windows. (You'll need to take them off when painting the can.)

Step 6: Completing the Circuit.

Now, let's get electrical. Connect both the motors parallelly and add a switch and input connectors to the circuit for the power supply. We need a 12v power supply is. We can use a 12v battery pack to run it or run it with an adaptor. (I prefer to use the battery as then it allows me to carry it anywhere.)

Step 7: Finishing.

Now comes personalization. To give a good look I've painted it matte black. I have installed the switch and input connector in it.| Adjust the water circulation pipe above the grass net as shown.

(PS: I had to use a water filter below the switch to cover the hole. You could also use a bottle cap.)