How to Make a Simple Steam Boiler

Remove the label from a large can of soup or juice and drill two holes, approximately 3/16-inch in diameter, in one end. Position one hole near the edge of the surface, with the second hole 1 inch closer to the center. Drain the contents of the can and rinse it several times with soap and water.

Solder two 3-inch lengths of 3/16-inch diameter metal pipe to the holes. Gently bend these pipes until their free ends point upward. Drill another small hole in the side of the can and solder the input nozzle of a pressure gauge to it.

Cut two lengths of rubber tubing, one 2 inches long and one 12 inches. Plug one end of the shorter tube with a machine screw and slide the free end over the outermost pipe. This will serve as the safety valve. Attach one end of the longer tube to the second pipe.

Test the safety valve by attaching the free end of the longer tube to an air compressor and adjusting the shorter tube's fitting on the pipe (how much of the tubing covers the pipe). Experiment until you find the point at which the safety valve blows off at 30 psi, as registered by the pressure gauge. Mark this point on the pipe and keep the valve fitted at this level.

Elevate the soup can using a wire stand, two stacks of scrap lumber, or another method of your choosing. The can should be situated in such a way that you can place a propane torch beneath it. Do so, after filling the can halfway with water, to run your steam boiler. Steam will escape through the longer hose, and can be harnessed to run a small steam engine.