Manufacturing process of Kiridashi knife
Cutting knives are manufactured through more than 15 processes even for general products.
If an error occurs in even one process, it will interfere with the subsequent processes, so uniform accuracy must be maintained for all processes.
Products are created by accumulating each of these "manufacturing".
①Material processing
Process the material to the required size（1or2)
1.Steel material for cutlery
Composite material with steel bonded to soft iron
②Forging
Heat in a furnace (950 ° -1050 °) and forge with a hammer to form ashape.
③Tempering
The structure of the steel that has collapsed due to forging is placed in a urnace heated at 780 ° and slowly cooled to spheroidize the structure of the steel.
④Engraved
Hit with a hammer to engrave.
⑤Tap with a hammer
Uniformize the structure of the steel spheroidized in the previous process.
⑥Remove distortion
Adjust while hitting with a hammer to adjust the deformation of the material.
⑦Molding
Mold the outer shape with a whetstone.
⑧Polish the back side
Polish the back surface with a whetstone to make it concave. (Rough polishing)
⑨Mud coating
Apply mud to the material. (Quenching becomes uniform)
⑩Quenching
Harden the steel by heating it to 800 ° and quenching it.
⑪Tempering
Elasticity is obtained by applying heat for 15 minutes in oil of 160 ° to 180 ° (SK material:160 ° C, White paper / blue paper: 180 ° C)
⑫Remove distortion
Adjust while hitting with a hammer to correct the deformation of the material caused by quenching.
⑬Polish the back side
Polish the back of the blade to a concave surface with a finishing whetstone. (Finishing)
⑮Finish Polishing of blade back side
The scratches on the back side of the blade made by polishing are finished in a hairline shape using polishing powder.
⑯Polish the back side of the cutting edge
Polish the back side of the cutting edge with a rotary whetstone.
⑰Dirt removal
Remove dirt from the product and apply cutting tool oil to the cutting ege.