Our combination pliers are manufactured according to DIN ISO 5746 which means that you have to pack 0.4 mm thick sheet metal. However, paper is thinner and can therefore slip through.
The background is as follows:
Combination pliers combine the properties of gripping and cutting in one tool.
With regard to the cutting edges, it is clear that they must close completely so that they can reliably cut even thin wires.
If the same requirement is now placed on the gripping jaws at the same time, this results in "overdetermination":
two functional surfaces, which lie on the same component but have a different distance to a common pivot point, are to take up a minimum value at the same time. This is theoretically impossible - a judgment then depends only on how accurately one measures.
It would also make no practical sense:
If it were possible, when new, to match the cutting edges and gripping surfaces so that they close at the same time, then after a relatively short period of use, natural wear in the joint and/or on the cutting edge, which also occurs in high-quality pliers, would cause the cutting edge to stand up a gap, making it impossible to cut thin wires.
At KNIPEX, we have given priority to the permanently safe function of the cutting edge over the gripping function on very thin parts. That is why we manufacture our combination pliers with a small gap between the gripping jaws.