The production of forged scissors and shears

Before a pair of forged scissors is fully finished, it will have passed more than 60 individual manufacturing steps. The most important processing steps for forged scissors and shears are shown below.

Manufacturing process

The raw material is given the appropriate form for further processing. For the production of scissors and shears flat material made of carbon steel is used (ZWILLING J.A. HENCKELS special formula). The most important processing steps are shown below.

  • Cutting to shape: slugs formed in the shape of long, pointed triangles are split from the flat material.
  • Heating: the slugs are heated up to white heat.
  • Forging: in the forging die (forging form) the slug is given its first rough shape of a scissor (upper and lower shear blades).
  • Cutting out the blank: burrs and excess material are cut away on an eccentric press and the scissor eye rings are punched out.
  • Milling of the closing surfaces (handle, joint area projection and the blade inset).
  • Drilling of the screw or stud hole.
  • Cutting the thread into the lower shear blade.
  • Stamping the trademark onto the joint area of the lower shear blade.
  • Hardening
    Stainless steel scissors: undercooling using the special ZWILLING J.A. HENCKELS ice-hardening process FRIODUR; these scissors are marked with “FRIODUR”.
    Forged scissors: blade and joint area are hardened up to the crescent; the handles need to stay soft because otherwise the following straightening process cannot be done.
  • Tempering: this heat treatment takes tension off the steel.
  • Hard-straightening: the scissor blades are pressed against each other (draw) and turned (twist). ZWILLING J.A. HENCKELS has optimised this hardening process.

ZWILLING J.A. HENCKELS uses the special ice-hardened steel for the Original Kitchen Shears and the TWIN scissors. The ice-hardening process stands for a further quality-determining refinement of the material.

Surface treatment

Grinding scissors and shears is an elaborate manufacturing process which is either carried out by hand (eye rings and handles cannot be machined) or by special precision machines. The most important manufacturing steps are:

  • Eye rings and shank: rough and dry-fine grinding inside and out.
  • Joint area and blade edges: rough and dry-fine grinding, smoothing, nickel-plating.
  • Grinding between, cutting edge and inner side: the grinding must follow the twist or turn of the blade´s inside.

In order to protect the surface against corrosion, scissors and shears made of normal steel are nickel-plated. Subsequently the scissors or shears blade are ground on the inside. Scissors and shears made of stainless steel are polished or brushed.

Assembly

The shear blades are screwed together. The cutting performance and the easy closing action along the whole cutting length of the scissors or shears are determined at this stage. ZWILLING J.A. HENCKELS fitters and controllers are highly skilled specialists.

The following steps are carried out during assembly:

  • Honing the cutting edges on the oilstone.
  • Screwing the shear blades together and pointing them, i.e. straightening.
  • Final inspection: testing the cutting property and action of the scissors or shears.