1 mineral water bottle and a small roll of medical gauze.
First, cut a piece of mineral water bottle obliquely with wallpaper knife. The one near the bottle mouth is 1/3, and the one near the bottle bottom is 2/3.
The remaining half of the mineral water bottle is the body of the "drinking bird".
Then make such a shelf out of a small piece of wood and wire. The tools needed are needle-nosed pliers and screwdriver. The function of needle-nosed pliers is more convenient to bend lines than ordinary line carving pliers.
Put a short piece of wire through the front of the mineral water bottle at the position of 1/3 and put it on the wire bracket made in advance.
Put the gauze into the mineral water bottle through the bottle mouth, soak it and put a small piece of gauze into the front glass.
Our waterbird is ready now.
The principle of "drinking bird":
When the gauze is completely wet and the bottom of the mineral water bottle is filled with water and sinks, slowly adjust its center of gravity until the head side is slightly heavier, the lever is out of balance and the bird's head sinks.
At this time, the gauze in the bird's mouth reached into the water in the cup. Because of capillary water absorption, more water is sucked into the bird's tail until the lever loses balance again and the bird's tail sinks.
After the tail sank, the excess water spilled out, so the bird's head sank into the cup again to "drink water", and so on until it could not suck water.
It is very important to complete the height of the wire support of this equipment. It is necessary to ensure that the bird's motion range is large enough, otherwise the water will not easily overflow when the tail sinks (the effect of surface tension), and it is also necessary to ensure that the water in the tail will not run over the lever position when the bird's head sinks.
In addition, it is also important to adjust the balance of the lever, which is the center of gravity of the drinking bird. It takes patience to move the gauze bit by bit until the effect is achieved.