Kong Jak (Rope-Cutting Wheel) — A flattened bottle cap with two holes punched through it. Thread a hemp rope through the holes, swing it so the rope twists into a spiral, then alternate pulling and loosening to make it spin.

"Swing the string so the bamboo-copter (kong jak) spins, until the string twists fully into a spiral. Once the spiral is full, pull and release alternately, and the wheel will keep spinning the whole time." (Sirindhorn Anthropology Centre, CC BY 4.0)

Place the crimped lid face up and use a hammer to pound it until the lid is flat. A crimped lid that has been flattened has jagged, sharp edges that can cut. Use cardboard instead for young children.

Punch 2 holes in the center of the lid with a nail, slightly apart.

Thread the sisal rope through the holes on both sides, then tie the ends of the rope together tightly.

Drawing of a chakram game (Sirindhorn Anthropology Centre, CC BY 4.0)

Insert your index fingers into the loops at both ends of the string. Adjust so the spinner sits in the middle of the string, swing it so the spinner rotates until the string is fully twisted, then pull and release alternately. The spinner will keep spinning. Can be played alone. Flattened pleated bottle caps have sharp serrated edges that can cut. For young children, use cardboard instead.

It is called "kong jak" (wheel/discus) because the flattened bottle cap with serrated edges spins like a wheel. Children also devised new ways to play, such as spinning it on a concrete floor to create sparks. A flattened bottle cap with serrated edges can cut. Younger children should use cardboard instead. Source: Sirindhorn Anthropology Center, Folk Tools and Utensils Database, "Kong Jak" (licensed under CC BY 4.0) **Limitations** The source does not provide the length of the string or the hole spacing as numbers.