The Jo, along with the bokken and tanto, is one of three wooden weapons used in the practice of Aikido and staff kata. It has its origins in the Shindo Muso Ryu - a koryu or "old school" martial art. The Kingfisher jo is made in 1 inch or 15/16 inch diameter and various lengths to fit personal needs.
The jo is a straight staff of unassuming character, linked historically with the Japanese sword. When compared with a live blade, it has some distinct advantages that make up for its simple shape and lack of a cutting edge. Unlike a sword, a Jo may be unexpectedly wielded from either end or any point in between. It also has a few more inches of reach than a sword. Although many weapons arose as a defense against the sword, some very effectively, the Jo is most notably associated with schools arising from traditional kenjutsu and is now used in the disciplines of Aikido and Jodo. Staffs are inconspicuous and, owing to their elegance and simplicity, are preferred by some martial artists above all other weapons.
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Quality Grade L5 jo are made with a flat end and chamfered edges.
Quality Grade L7 jo are made with a slightly domed end. This provides a very strong geometry while still providing an edge for control and proper hand orientation.
Quality Grade L7hc jo are made with a slighly domed end that reveals the multiple facets of the hand cutting process. In this photo, you can also see tool marks on the side of the jo as L7hc weapons are finished by the action of drawknife, spokeshave and hand cutting tools. This level of workmanship is evident of woodwork that predates the introduction of commercial sandpaper. As far as wooden martial art weapons are concerned, the thousands of little facets, only visible upon close inspection, are readily felt by the hand and give the user an unparalled torsional grip on the wood.