Countersink

(noun.) a hole (usually in wood) with the top part enlarged so that a screw or bolt will fit into it and lie below the surface.

录入:温德尔

• At the pit end, circular slots are cut and holes bored for the purpose of countersinking and fastening the pin spots. 佚名. 神奇的知识之书.
• When the rail has been formed, the ivory diamond-shaped squares and name plate are countersunk into the top. 佚名. 神奇的知识之书.
• Screw holes, countersunk, are bored from the top down through the slabs, around the outer edges, through which the slate is screwed to the frame. 佚名. 神奇的知识之书.

手打:奈杰尔