FAÇONNER LA MATIÈRE
CHOICE OF WIRE - Step 1
It must be the right diameter, and its chemical composition and hardness must conform to the company's quality standarts. BOHIN France uses demagnetized wire made of fine carbon steel. Since steel is too dry, the wire is covered with copper, insuring a smooth passage through the first machines.
STRAIGHTENING AND CUTTING TO LENGTH - Steps 2 and 3
After choosing the wire, it passes through rotating clamps that break down the neutral fibers so it lies straight. Then the same machine cuts the straightened wire into segments equal to the lenght of two needles.
POINTING- Step 4
Both ends of the section are sharpened to make the points of two needles. The grindstone gives the point a rounded cone shape so it can go through fabric easier.
STAMPING AND PUNCHING - Steps 5 and 6
Aside from its point, the cut section does not look much like a needle. One machine combines two operations to make the eye. Stamping : a die marks the location of two eyes by crushing the center of the steel wire.
Punching : an awl opens the hole which has already been started by the stamping die.
SEPARATING THE CUT SECTIONS AND DEBURRING - Steps 7 and 8
One machine separates the sections into two separate needles, and removes burs from the eye. Each side of the piece is separated in its center. During the stamping process, a chip was formed near the head of the needle when the metal was crushed.