Treatise on Armament Technology, Volume 103

Crossbow Formations: Crossbow Mechanisms, Part 2

Page 8

The antler component original: lujiao (鹿角); high-quality antler was used for its durability and smooth surface in the moving parts of the trigger mechanism has a length of 1 inch and 7 or 8 fen A fen (分) is roughly 0.1 inches or 3.2mm. Its thickness is 5 fen or 4 fen, and the height of the head is 1 fen.

The thickness at the top surface of the bow-socket hole original: yanyan (檐眼); the aperture where the bow-lathe sits is 2.5 fen. The tendon-groove hole original: ganjinyan (干筋眼) is located 1 inch and 5 fen below the stock's support. The end of the tail is reinforced with an antler inlay sleeve original: xianggu (鑲箍); a protective ring or fitting that is 5 fen long.

The tip of the head is tapered like a weaver's shuttle; the top surface is rounded and somewhat narrow, as is the bottom, while the middle section is plump and full.

The trigger-pull hole original: bo jiyan (撥機眼); the opening where the finger engages the trigger must not be made too large; it should be just wide enough to accommodate a finger. The entrance is small, but the interior is hollowed out like an eggshell This indicates a vaulted internal chamber that allows the trigger to move freely while maintaining structural strength at the surface. The hole is 1 inch long and is positioned 1 inch away from the top surface.

If this 1-inch distance is not maintained, there is a danger that when carving the cushion-block hole original: dianyan (墊眼); a cavity for a spacer or stop-block, the two openings will break through into each other. If they are interconnected, the cushion-block may fall into the trigger-pull hole when the crossbow is discharged, causing it to strike the shooter’s finger. One must be aware of this potential defect.