How to Perform a Crimp Test

Crimping, is the process of mechanically joining two pieces of ductile metal by bending one or both of them in a fashion known as a ‘crimp’. This process is commonly used to join and terminate wires in a custom cable assembly. In this crimping guide, you will learn all about the practices and procedures used to create the best possible cable assemblies, as well as how to assess the quality of your crimps to maintain customer satisfaction.

What is a Crimp?

When creating a crimp, a technician will typically strip the end of the cable to be crimped, and place the strands of wire into a metal terminal. Force is then applied to this terminal using a crimp tool, a crimp press, or a crimp die. The force of the crimp deforms the wires securely to the terminal, and ensuring a strong electrical connection between the wire and the terminal.

You can order an “Amazon’s Choice” Titan Tools 11477 Ratcheting Wire Terminal Crimper for $18.40, and good selection of 480pcs Wire Terminals Crimp Connectors for about $18.

For specialty type connectors, like the Ethernet / RJ45 pictured above we recommend buying the $20 Maxmoral 7 in 1 Cable Tester + Crimp Crimper + Wire Stripper + 50 RJ45 CAT5 CAT5e Connector Plug + 100 Cable Ties + 100 Cable Cord Holder Clips + 2 Ethernet Connector Network Tool Kits

Why Use Crimping?

Crimping is a favored choice amongst wire harness manufacturers for a number of reasons. For one, crimping is a relatively inexpensive method. Crimp tools can be bought for extremely low prices, and the process of crimping itself involves placing the wire on the terminal, feeding the terminal to the tool, and applying force. On average, technicians can crimp between 10-20 assemblies per minute, and require minimal training.

Additionally, no other tools or raw materials are required to perform the crimp. Finally, it is a statistically reliable method for creating a good electrical contact between a wire and a terminal.

Qualities of a Good Crimp

The quality of a crimp is determined by two factors: the way the wire was stripped and the general shape of the crimped terminal. Wire must be stripped evenly, so that all of the wire strands are exactly the same length with a centimeter or more of the wires exposed. The insulating jacket surrounding the wire strands should also be cut evenly, being careful not to cut or scar the wire strands. The terminal itself should be symmetrical, or evenly overlapping.

Pull Testing

To test your crimped connections, no method has proved less costly or easier to implement than the pull test. To perform the pull test, a crimped wire is placed into a device that gently bends and stretches the connection, until it reaches the limit of its tensile strength (which is measured and recorded) until it finally breaks. Tensile strength has been shown to be an incredibly reliable indicator of electrical connectivity and durability of the connection. Additionally, the equipment required for the test is incredibly inexpensive, and easy to learn how to use, making it a low-cost quality assurance method.

Wires of Different Sizes

When coupling two wires of varying sizes, the smaller wire should be placed on the bottom of the crimp, underneath the larger wire. When pull testing such a connection, it is important to only test the smaller wire, and use this reading when assessing the quality of the crimp. The reason for this is that a smaller diameter wire of equivalent material has less tensile strength.

For more information on how you can implement appropriate quality assurance techniques into your custom cable assembly production line, visit LoDanElectronics.com now!