Wire stripping – quick, simple and safe

The best tips on how to efficiently cut wires

A clean and straight cut that neither deforms nor damages the wire is of particular importance when working with wiring so as to ensure that safe and dependable connections can be made. Every user has her or his own preferred wire-stripping technique. However, in principle, it is possible to distinguish between two different cutting techniques: shear cutting and wedge-action cutting as it is generally referred to. Both techniques are in accordance with the DIN standard 8588.

In the case of shear cutting, the wire is severed by two cutting edges that move past one another. This technique is used primarily when cables, wires or conductors out of copper or aluminium have to be stripped. High quality wire stripping tools are equipped with an integrated cutting unit that is specially designed for these types of materials. As a result, the cut can be implemented with little effort, efficiently and in a tool-friendly manner.

However, wedge-action cutting is the preferred choice whenever hard metals need to be severed. In this case, the cable is pushed apart by one or two wedge-shaped cutting edges and severed.   

For both cutting techniques it is a case of: to ensure fast and safe work, the cutting unit needs to be an optimal fit from an ergonomics point of view.

Such risks can be counteracted when modern and requirement-specific tools are selected. They adjust automatically to the respective cross section and the insulation thickness, enabling an optimum stripping of the cable. Additionally, special pliers have been developed for handling extremely thick and even very thin insulation layers. These tools do not only have the automatic self-adjustment feature, but can also be set manually to the required cross section. This means that the very highest level of safety is guaranteed no matter what the circumstances or requirements may be. However, in the case of extremely thick insulation layers, it is advisable to firstly make a wire-stripping test on a specimen cable.


Automatic self-adjustment instead of fixed blade

In everyday, practical situation, cable stripping knives with a fixed blade still continue to be used. Yet for safety reasons, the use of these types of knives should be avoided since the danger of injury is not inconsiderable. Frequently, cable sheath removers or even stripping knives with adjustment screws are used as alternatives – but even these types of cutting tools have significant disadvantages. Since the cross sections of cables and wires cannot be measured and determined physically but are calculated on the basis of the conductance, the cross section value is consequently reduced when leads are severed during the wire stripping process, something that is not uncommon. This may result in contact resistances and, at worst, cable fires.

 


Superfluous and hazardous: the shortening of protruding leads

In practical working processes, the stripping of cables and wires often involves far more effort than is really necessary. After a lead has been stripped and a cable end-sleeve attached and crimped, it is sometimes the case that protruding leads then have to be shortened. Such a subsequent cutting process is not only superfluous, it is also dangerous. There is, for instance, the risk in switching cabinet construction that some of the leads are already connected in existing circuits and consequently cause a short circuit.   

It is therefore advisable to use an automatic wire stripping tool that has adjustment settings for the wire stripping length. Optimally, it should feature a combination out of adjustable length stop and a scale that shows both the metric dimensions as well as the inch sizes for AWG cables (American Wire Gauge). One great advantage is that the stop ensures a constant and consistent insulation length.  

To enable optimum results to be achieved, the length of wire to be stripped should always represent the length of the sleeve plus 2 mm.  Ideally, only 0.05 mm at a maximum should protrude from the sleeve shaft when the cable is inserted into the sleeve. In the case of twin cable end-sleeves, the length of wire to be stripped should always represent the length of the sleeve plus 3 mm – the reason for this being the insertion funnel. 

Conventional push-in clamps have a clamping mechanism that is relatively far away from the insertion funnel. In these cases, the best results are achieved when cable end-sleeves with a greater sleeve length are applied. For example, in the case of screw clamps with a cross section of 1.5 mm², cable end-sleeves with a sleeve length of 8 mm are used. It is important to strictly observe the manufacturers’ instructions when using push-in clamps. For safety reasons, it is advisable to select a length dimension that is one higher. In other words: a sleeve length of between 10 mm and 12 mm is best suited for a cross section of 1.5 mm².


Tools for complex requirements and high user convenience

Application-specific cable with high insulation requirements is used in many different sectors. The shipping industry, for instance, places great demands on cables and wires with its international approvals – and in switching cabinets as well as in machinery and equipment construction, halogen-free wiring has long been the standard. To enable good insulation properties to be achieved despite such demanding requirements, insulating material out of PE or TPE is frequently used. 

A number of different material properties, from soft to ductile and brittle, all contribute to making the professional stripping of wire a real challenge. The right tool is therefore all the more important to enable the insulation to be perfectly removed. Wire stripping tools by Klauke are equipped with innovative cutting edge features and special blade geometries. The wire strippers 43/2V and K43/2U are designed for cross section ranges of 0.08 mm2 to 16 mm2 and remove even complex insulating material efficiently and cleanly. Even sheathing material out of silicon or hard insulating substances, as can be found on UL-specified cable types, present no obstacles whatsoever for the Klauke wire strippers. When simply PVC or PVC-similar materials are used, Klauke offers a professional wire stripping tool K43/3 with an extreme cross section range of between 0.08 mm² and 16 mm².

Besides efficiency and safety, a good wire stripping tool should offer one thing in particular: ergonomy.  Since every gram counts for the user to enable her/him to work easily over a sustained period, low weight is absolutely vital whenever tools are concerned. Wire stripping operations that have to be carried out several hundred times a day is not uncommon in the switch cabinet construction and engineering areas – and that represents a great strain on the hand and arm muscles. Klauke wire stripping tools such as the K43/2V and K43/2U feature outstanding ergonomics. Their weight of only 140 Gram ensures sustained work and combines this with great convenience.

The usage of the wrong tool may result in an inaccurate removal of the insulation:

 

Accurate removal of the insulation with the right tool:

 


Tool selection: quality is decisive

The selection of the right wire stripping tool should particularly be in focus when wire stripping operations are to be carried out safely. In any case, it is crucial that the tool has a high quality and meets the essential demands placed on flexibility, safety and user convenience: after all, good wire stripping is a precondition for safe and longlasting connections.

Wire stripping tools by Klauke:

    > For PVC insulations and halogen-free conductors: K43/3 K43/2
    > For PVC insulations, specially-insulated and extreme
       conductors: K43/2V & K43/2U