Crimping: an alternative to soldering.
Your first thought might be to use a soldering iron to make electrical connections but have you ever considered using a crimping tool?
During the soldering process, the wires or inner conductors are stripped and soldered in sleeves or at contact lugs/contact points. This method is used for both antenna cables and multiple connectors of various types.
Self-made soldered joints rarely produce a uniform result. Individual wire strands can be missed and not soldered effectively, so they protrude laterally. Also, soldered connections in plugs or couplings can only withstand limited mechanical loads. If multi-pin cables are connected to a plug or a socket, there may also be space problems during soldering. In the case of closely adjacent cores, the insulation of the protective sheath of an adjoining core can melt during soldering. All this increases the risk of a short circuit with an adjacent contact.
How to use crimping tools
Crimping is a reliable alternative to soldering. In this case, conductors and cables are pressed into corresponding connectors or sockets using a special “crimping tool”, usually with adjustable pressure.
In the simplest case, for example, the inner conductor of a coaxial cable is pushed into a wire end ferrule, which is then pressed or crimped with the appropriate pliers. Cable lugs (flat plugs, flat receptacles, notched lugs, loudspeaker lugs, notched lugs, butt connectors, etc.) for loudspeaker cables, 12-volt automotive wiring, etc. have also been pressed for decades with appropriate crimping pliers, such as current ones with the “crimping pliers KNIPEX 9721215” (see below).
Crimp technology is frequently used for the assembly and repair of connecting cables between PCB pin strips. For this purpose, there are various single and double row socket strips (e.g. from JST), which are each designed for a corresponding grid dimension (e.g. 2mm). The socket strips contain rectangular or square cavities for socket contacts, which usually snap in automatically during insertion to secure against accidental removal. For contacting, the wires of the connecting cable must be stripped to a defined length and then crimped with a crimping tool suitable for the socket contacts used. The crimping tool WC-240 from JST, for example, is used for the 2mm pitch and the JST socket strips.
Crimping technique for smaller dimensions
The crimping technique is suitable for even smaller grid dimensions. Here, however, the contacts for individual cores are no longer just crimped, but the entire plug. The corresponding crimpable connectors usually have contact rows with integrated cutting blades and holes for targeted insertion of the individual cores. If all cores are in the holes of a four-pin Western telephone plug (RJ10) or an eight-pin patch cable/network cable (RJ45), for example, a suitable crimping tool cuts the protective sheath of the core in the correct position. The design of the cutting blades in the plug means the cores of the cable are not cut through but are surrounded by the cutting blade for a clean cut. Even pressure from the crimping tool gives a clean cut allowing a good current contact and a strain relief of the cable in the protective sheath.
Product 1: KNIPEX crimp tool for insulated terminals and cable connectors
KNIPEX pliers 97 21 215 are suitable for occasional work with insulated cable lugs of various types (flat plugs, flat receptacles, fork notched lugs, loudspeaker cable lugs, notched lugs, butt connectors, etc.) It has a wire cutter and stripping openings for six wire/strand diameters between 0.75 and 6mm² inside the handle. At the other end, the pliers have three colour-coded squeezing openings for pressing the corresponding cable lugs of the same colour.
- Beginner-friendly, easy handling
- Suitable for conductor cross-sections from 0.5 to 6.0mm²
- Crimped insulated cable lugs and butt connectors
- Suitable for home and hobby use, as well as occasional crimping in the commercial sector
- Also offers an integrated cable cutter and stripper
Product 2: KNIPEX PreciForce, a professional crimping tool for insulated terminals and butt connectors
If you often have to crimp professionally insulated terminals and connectors, you need precision pliers with lever travel ratio to reduce the required manual force and protect your hands. These pliers are:
- Characterised by its power amplification thanks to optimum lever transmission
- For fatigue-free work
- Suitable for conductor cross-sections from 0.5 to 6.0mm².
- Great for crimped insulated cable lugs and butt connectors
- Ideal for regular use in commercial and industrial environments (switch cabinet construction, etc.)
- Available with precision profiles for particularly clean crimp connections
Product 3: KNIPEX ferrule pliers
This robust 180mm short crimping tool for other end ferrules is made of chrome vanadium electric steel. It offers calibrated crimp pressure and adjusts itself to the respective core sleeve size used. An integrated toggle lever increases the force for fatigue-free work. This tool is:
- For crimping ferrules according to DIN 46228 part 1 + 4
- Self-adjusting adaptation to the desired core sleeve size
- Suitable for all twin wire end sleeves in the capacity range 0.08 – 10 + 16mm²
- Produces consistently high crimp quality due to ratchet (unlockable)
- Comes with pre-set precise crimp pressure – calibrated at the factory
Product 4: Crimping pliers for JST contacts for industrial applications
The JST crimping tool WC-240 is ideal for working with single- and double-row JST socket strips for the 2mm pin strip spacing and enables, for example, the precise crimping of standard JST PH crimp contact sockets.
- Indispensable for standard-compliant processing of JST contacts PH-002-(P) 0.5S
- Ratchet pliers with easily adjustable load pressure
- For regular use in commercial and industrial areas
- Equipped with a locator to ensure the correct positioning of the contact during crimping
- Three different wire holders for wire sizes 24AWG (0.62-0.67mm) 26AWG (0.57-0.62mm) and 28/30AWG (0.55-0.60mm and 0.52-0.57mm respectively)
Product 5: KNIPEX crimping pliers for Western and modular plugs
The 190mm long KNIPEX KN 97 51 10 crimping tool is suitable for the precise crimping of six or eight cores of RJ12 or RJ45 Western plugs. A lever transmission integrated into the pliers ensures fatigue-free working.
- For use in telecommunications and networks
- For cutting and stripping of flat telephone cables and grouting of 6 and 8 pole modular connectors, RJ 12/RJ 45
- Exact crimping process due to parallel crimping
- Energy-saving lever mechanism
- Length cutter and stripping knife for 6 and 12mm
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