After extensive research, precise measurements and actual handling of real specimens. LK Chen integrated all the primary data and personal handling experience to come up with a Blade Design Specification for each of the Jian. Blade Design Specification details the form and structure of the blade in terms of blade length, handle length, width at various part of the blade, the final target weight and where to start the tapering. It also specify the type of steel to use, the hardness, elasticity and sharpness and what level of polishing and finishes required. In addition to the blade design for the swords smith. LK Chen also come up with the design for the fittings for the bronze casting workshop, And finally, the design of the scabbard and the hand painted pattern on the scabbard to complete the sword.
There is always subtle considerations and tradeoffs between blade cross section profile specially for the Chu Jian. Chu State was famous for the Chu Jian since it is the first and most famous steel Jian, contemporary with the bronze sword. So Chu Jian took on the blade profile of the bronze sword and adjust it for the new material, steel.
The cross section profile on the left is called wide shallow groove and the profile on the right is called flat groove. Shallow groove offer a narrower edge angle and therefore swords with this groove pattern have sharper edge. The flat groove on the right have steeper edge angle and is not as sharp. However, flat groove offer a thicker and sturdier blade than the one with wide Shallow groove, Another factor is the width of the groove. If we divided the blade in half with the ridge. The groove part take up some of the width and the edge take up the rest. If the the edge is one third and groove is two third, than we have a wider edge and be able to make a sharper edge. If the width of the edge is one fourth and the groove is three fourth (like the flat groove on the right) than the blade is more sturdy but less sharp at the edge.
Every swords smith have their own preference on groove profile based on their experience and aesthetic sense. The sword smith can even adapt an in between profiles based on the length of the blade. For example, longer blade need to be more sturdy and therefore closer to the level groove while shorter blade tends to take on the shallow groove for sharper edge.
Magnificent Chu Jian blade profile
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