Clinching describes the forming of a Clinchlok joint.  A Clinchlok joint is formed when the upper tooling squeezes the two ply of material joined between a punch and die. The strength of the Clinchlok joint and the life expectancy of the punch and die are both determined by the amount of squeeze. It is important to note that because the die is of a very special design, the Clinchlok is able to “mushroom”. Like the die, the punch in a Clinchlok joint is also of a special design that has a rounded edge, rather than a sharp edge like a normal punch.  This rounded edge is known as the punch tip radius. To form a Clinchlok joint, neither the punch or die can be sharpened.

If different thicknesses are to be joined in a Clinchlok, best results occur when the thicker material is on the upper (punch) side of the two ply but this material should not be more than twice the thickness of the thinner material. The combined thickness of the two ply should not exceed the combined maximum thickness recommended for the die.

Clinchlok joints made of other materials can be joined with our SURELOK II machine as long as the materials are not harder than commercial quality mild steel. In most cases both ply should be of the same hardness. If a different hardness is used for each ply (not recommended) the harder material should be on the upper (punch side), if possible.