If you’ve ever looked into replacing your own car stereo, then you’ve probably run into the terms crimping and soldering. It’s necessary in order to electrically join the vehicle to the new stereo. Without the proper connections the wires could short out, and potentially damage your brand new stereo.
Crimping and soldering are both methods of joining and terminating wires. Soldering is more labor-intensive but creates a better and more reliable connection. Crimping, on the other hand, was developed as an alternative to soldering as it provides a high quality connection between a terminal and a wire at a lower cost. There are instances in which one is preferred over the other, but today we’ll be focusing on how to achieve a quality crimp.
We take crimping seriously because proper crimping is crucial when working in the cable and harness industry. Wire harnesses are needed to power medical, military, and transportation equipment. If these systems fail, it could cause fatal consequences. Poor crimping results in increased heat resistance and eventual connection failure. Could you imagine trying to figure out why medical equipment has failed only to realize that it’s due to a few faulty wire connections? How would you know the extent of these faulty connections? You’d have to start from scratch, wasting time and resources. That’s why we’ve compiled a few Crimping Tips to guide you in the right direction.
Crimping Tip #1 Prep the Wires
Before crimping a wire, you must first select the correct wire gauge and strip a specific length of insulation from the wire. Both the insulation and wire must be cut perpendicular to the wire’s longitudinal axis. All the wire strands need to be approximately the same length and without any excessive amount of strand damage. Wire preparation is the first step towards a good crimp. Overlooking this step could cause unwanted complications later in the crimping process.
Crimping Tip #2 Skip the Pliers
Pliers are not crimpers. Crimpers are specially designed to deform the wire and insulation in certain locations with the proper force and join the wire and terminal together. Whether you opt for hand-held tools or fully automated systems, do not skimp on quality. Quality tools will ensure a secure electrical connection that won’t pull apart easily. Higher quality crimpers often have built-in features that won’t allow the crimper to re-open until a sufficient force has been applied. Fully automated systems will further guarantee proper crimping. Some automated crimping machines even strip the wire to the proper length increasing your efficiency.
Crimping Tip #3 Avoid Over-Crimping
Yes, over-crimping is possible. This happens most often when using hand-held tools. If this method of crimping is necessary, it’s best to use tools with self-locking features that release only until enough pressure is applied. When using automated crimping tools, over-crimping usually translates to inadequate crimp height. Over-crimping could cause excessive extrusions or flares on the bottom of the conductor crimp. It also reduces the circular area of the conductor and increases resistance. Adjusting the crimp height to the proper specifications should resolve the issue.
Crimping Tip #4 Visually Inspect the Crimp
Visually inspecting the crimped wire can usually help detect most defects. Defects to look for include: pierced insulation, absence of bell mouth, short or no conductor brush, insulation under the conductor crimp, and excessive or no cut-off tab. Using an eye loupe can aid in examining the small details of the crimp.
Crimping Tip #5 Test Wires Regularly
After all the necessary wire preparations and a smooth crimping process, the last step would be to test the crimped connection with a pull test. A pull test is a quick, destructive way to determine the mechanical properties of a crimp termination. The test confirms the proper amount of applied force during crimping. Testing at regular intervals and whenever there’s a change is tooling or supplies makes it easy to spot irregularities ahead of time.
Achieving a quality crimp takes skill and much practice. It requires great attention to detail and patience. Perfection is often unattainable; however, it is something to strive for.
Our electromechanical manufacturing division at Trimantec has assembled wire harnesses for use in medical and military equipment. Therefore, the wire connections our team makes need to be precise, secure, and reliable. We take wire crimping very seriously, and you should too.
Do you have your own tips for achieving a perfect crimp? Share your expertise with us in the comments below!