Tempering gives hardness to the knife to ensure a long lasting cutting edge. It’s a very important operation.

 

The knives are carefully placed in special trays. They are put into the furnace at 820° centigrade.

 

After a period at these high temperatures, the knives are immediately placed into oil.

 

The knives are then put back into the furnace to "return" hardness to the steel (200°-300° C).

 

For the Carbon Knives, we verify their straightless, one by one.

But, steel has a certain memory, and it is sometimes very difficult to have extremely straight blades, especially for large knives.

It's not really a defect. We make every effort to have straight blades, but we can not do anything to go against the memory of steel.