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Cheness SGC Series
(Specialized Goza Cutters)
The Tsukikage Ko Katana shares the same blade as our Yamakami Ko Katana. Both swords uses the Cheness SGC blade design and is especially made for goza (tatami omote) cutting exercises.
The photos below shows the overall appearance of the blade in and out of the saya. This is a significantly broader sword with a narrower entry angle in its cutting edge.
Due to the nature of the geometry, the blade exhibits a hint of a pattern of how the quench affected different parts of the blade differently than the normal katana even though this is a through hardened blade.
The Tsukikage uses a black cotton ito wrapping with a blackened steel tsuba and an image of rabbits under a crescent moon. The steel used on this blade is the through hardened version of the Cheness 9260 Spring Steel.
The handle of this blade is slightly bigger than that of a standard katana. This is to compensate for the broader blade and nakago within the handle.
The photos below are comparison of the Cheness SGC Series blade and a standard katana. The SGC blades are thinner but broader than the standard blade for purposes of improving its cutting performances.
The lateral strength of the SGC is just as strong if not stronger, even though it is thinner, because of the additional material in the height, providing support. Overall, the weight of the blades on the SGC is heavier, but well distributed and its center of gravity does not change from that of a standard katana at 6" above the tsuba.
All components on the SGC had to be re-cast... Including new machined mold for the fuchi, kashira, habaki, etc. The Saya is also significantly more substantial.
The purpose of changing the blade cross-section geometry in making the SGC is to significantly reduce the entry angle of the cutting edge without reducing weight or lateral strength of the blade.
As illustrated in the diagram below, this change makes the SGC significantly better at cutting. It is especially well suited for exercises in cutting of goza mats or tatami omote. This blade also handles bamboo extremely well.
Because of the Cheness 9260 Spring Steel employed in these blades, the cutting edge holds up to the rigors of cutting exercises where other steels would crumple or roll edge under this blade geometry.
The concept of this new design is based off of a $5,000 custom wakizashi blade made especially for cutting exercises for some high ranking iaito sensei.
It took more than half a year in planning, preparation, re-casting, machining of new molds to bring this blade into a production basis and effectively dropping the price down to less than a tenth of what it would have, otherwise, cost to produce a similar blade in the past.
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