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 1040° centigrade.
After a period at these high temperatures, the knives will be placed in a machine to straighten them during the cooling time to prepare the Grinding Operation.
The knives are then put back into the furnace to "return" hardness to the steel (200°-300° C).
After the process the knives will have an hardness of 54 - 56 Rockwell, that is to say the resharpening will be easy with a steel.