เครื่องสีข้าว (khrueang si khao) — a Woven Bamboo Upper Part Packed with Clay Turns on the Lower Part, Cracking the Husk Off to Brown Rice

"To mill the rice, paddy is put into the deep hollow of the upper toothed part, which is turned clockwise by hand with the lever until it gives brown rice; this is then pounded to white milled rice for cooking." (Sirindhorn Anthropology Centre, author พิชชา ทองขลิบ (Phitcha Thongkhlip), CC BY 4.0)

Weave bamboo-skin strips into a tray with a high rim and bore a hole for the brown rice to run out into a container. Stand a wooden spindle in the middle and pack clay firmly round it, sprinkled with salt water. Make the teeth of thin hardwood slats alternating with clay mixed with rice husks, packed tight all round the face.

Weave bamboo-skin strips into a round body about 50 cm high and 50 cm across. Pass a squared hardwood crossbar about 2 metres long through it so it sticks out 25 cm on each side, and bore a hole in each end. Pack it with clay sprinkled with salt water, leaving a hollow in the middle for pouring the rice. Make teeth on its underside as on the lower part.

Make a lever from a large bamboo with a handle, bore a hole in its end and make a peg to fit the hole in the crossbar. Set the upper part on the spindle of the lower part.

Real photos of a เครื่องสีข้าว (khrueang si khao) from พิพิธภัณฑ์พื้นบ้านจ่าทวี (Ja Thawee Folk Museum) (Sirindhorn Anthropology Centre, author พิชชา ทองขลิบ (Phitcha Thongkhlip), CC BY 4.0)

Pour paddy into the hollow of the upper part and turn the lever clockwise. The paddy runs down between the upper and lower teeth, the husks crack off, and the brown rice runs out through the hole into the container. Then pound it in a mortar into milled rice.

Hulling rice works much like grinding flour in a mo. Pounding the brown rice in a mortar is called som khao. The salt water sprinkled on helps the clay bind tightly and keeps termites away. Source: Sirindhorn Anthropology Centre, Traditional Objects of Everyday Use database, "เครื่องสีข้าว" (CC BY 4.0 licence). **Limits** The source gives neither the number of teeth nor the proportion of clay to rice husks.