Kong Chak (Thai Bottle-Cap Whirligig, Chak Tat Chueak) — a Crown Cap Hammered Flat, Pierced Twice, on a Hemp-Cord Loop; Twist it up, then Pull and Ease to Spin

"Swing the cord so the kong chak spins until the cord is fully twisted; when it is fully twisted, pull and ease alternately, and the kong chak spins all the time." (Sirindhorn Anthropology Centre, CC BY 4.0)

Lay a crown cap face up and hammer it flat. The flattened cap has a sharp serrated edge and can cut; for small children, use card instead.

Punch 2 holes in the middle of the cap with a nail, a little apart.

Thread hemp cord through both holes and tie the ends together firmly.

Drawing of playing with the kong chak (Sirindhorn Anthropology Centre, CC BY 4.0).

Hook both forefingers into the cord loop, one on each side, and centre the kong chak on the cord. Swing it until the cord is fully twisted, then pull and ease alternately; it keeps spinning. It can be played alone. The flattened cap has a sharp serrated edge and can cut; for small children, use card instead.

It is called kong chak because the flattened cap's serrated edge spins like a wheel; children invent new ways to play, such as spinning it on concrete to throw sparks. The flattened cap has a sharp serrated edge and can cut; for small children, use card instead. Source: Sirindhorn Anthropology Centre, Traditional Objects of Everyday Use database, "กงจักร" (CC BY 4.0 licence). **Limits** The source gives no cord length or hole spacing in numbers.