Crimping Tools

By Jeff Griffin | Jan 16, 2023
Crimping is a common method of connecting two wires and terminating electric and datacom connections.




Crimping is a common method of connecting two wires and terminating electric and datacom connections. Pressure applied by a crimping tool deforms or reshapes a wire’s metal to join it to the conductor. A correctly made crimp provides a good connection that is resistant to vibration and sudden temperature changes.

Experiments with handheld crimping tools date back to the late 1950s, and by the early 1960s, several brands of manual crimping tools were available, providing a fast, solderless method of making connections.

Today, several manufacturers offer lines of quality manual and battery-powered crimpers with attention paid to ergonomics. The introduction of battery-powered crimpers increased the ease and speed of crimps while reducing the risk of wrist and hand injuries from repeated use.

Ryan Berg, director of product management at Greenlee, Rockford, Ill., said manual and battery crimpers have become more ergonomic.

“One of the biggest improvements is the introduction of insulated battery crimpers, which add additional layers of protection from live voltage,” he said. “The patent-pending tri-insulation barrier in Greenlee’s line of insulated battery crimpers and cutters impedes voltage from discharging between the head of the tool and the tool user’s body.”

Greenlee 6-ton inline cordless crimper


While some multipurpose tools include crimping, Berg said these tools may not have capabilities of a dedicated crimper.

“There are multiple models of crimpers that are ideal for electrical technicians and maintenance professionals who need tools with battery-hydraulic power,” he said.

When evaluating crimpers, Berg suggests asking these questions:

  • Work environment: Is this a low- or high-voltage application? Will there be energized lines nearby? Will work be overhead, from a bucket truck or in a tight panel box?
  • Voltage: Is the additional protection from voltage that insulated crimpers provide necessary?
  • Volume: How many crimps will be made? How frequently will this number of crimps be needed on a job?
  • Wire specifications: What are the sizes, type of insulation, conductor materials and connector types?
  • Connector: What type(s) of conductors will be used?
  • Die versus dieless: Dieless crimpers are faster because it isn’t necessary to switch out the die to crimp a different size, Berg said. However, dies usually allow a larger range of sizes to be crimped.

Using an insulated crimp tool when making crimps in high-voltage environments or near live wires or energized equipment offers a layer of protection (in addition to required PPE for energized work areas and working at heights) that manual crimpers don’t provide.

“Always remember, using the wrong connector may result in the crimp not passing inspection, and it could also impact the reliability and safety of the connection,” he said.

 Troy Marks, group product manager at Milwaukee Tool, Brookfield, Wis., said several factors influence what crimper a professional will use to correctly complete a job.

“These factors—including elements such as connector type and size—play an important role in determining the best crimper to use, while wire size and wire type also help determine the best crimper for specific uses,” he said. “Application orientation also determines which crimper to use. For example, linear-style crimpers deliver the best performance in tight spaces, while pistol-grip crimpers are better suited for above-the-shoulder applications,” as they are often easier to align.

Hilti NUN 54-22 cordless 6-ton cable crimper and cutter

Marks said battery-powered crimpers have significantly increased throughout the industry in recent years because they improve productivity on the job while providing ease of use and reduced fatigue.

“Most low-voltage connections continue to be manual, and we are seeing a dramatic shift away from manual crimping tools and hydraulic crimping heads for larger-sized power connections toward self-contained battery-powered crimping tools,” Marks said. “Specifically, battery-powered crimpers have been created to better fit unique user needs and environments as well as orientation preferences for specific applications.”

Marks said while multipurpose tools that crimp can be effectively used in these applications, crimp-only tools make connections without any compromises.

“For example, multipurpose tools that crimp are often larger in size or a heavier weight due to features and functions from the addition of multiple applications in one,” he said.

David Walker, business unit leader at Hilti, Plano, Texas, said commercial electricians and utility lineworkers generally consider the size of the cable and the lug or connector to determine the force needed (i.e., 6-ton versus 12-ton). They also have the option of dieless or die crimpers for 6-ton applications.

Jonard CT-200 universal compression tool


“We are seeing battery-powered crimpers being used most commonly,” Walker said. “Manual crimpers are a rarity in the field now. The benefits—ergonomics, safety, etc.—of a battery-operated tool versus a manual tool are outweighing cost difference. Manually operated crimpers are moving toward obsolescence due to the ease of use and mitigation of workers’ comp incidents related to the strains of manual crimpers.”

Walker said there are multipurpose tools that include crimping, and one of Hilti’s most popular tools is a universal cutter and crimper.

“We find that customers enjoy having one tool that can handle two applications,” he said.

Paramount to proper crimping is the appropriate connector for the cable size and application.

Ed Scirbona, senior director of engineering at Jonard Tools, Elmsford, N.Y., said in some instances, the same crimping tool can be used for electric and low-voltage work.

“For example, a ratcheting crimp tool can make easy work of small ring and spade lug-type terminals and can tackle some of the same connectors used in electrical applications where the connectors are more robust and require more force to crimp. It’s about having the correct die set for the application,” he said.

Panduit 15-ton crimping tool


Several factors determine the tool choice.

“In reference to low-voltage is the need for ring lugs on various grounds, [and] ring or spade lugs for more secure electrical connections. Considerations for types of crimpers include price, crimper use and size of lugs being crimped, to name a few,” Scirbona said. “The types of crimpers range from plier types, to ratcheting crimpers, to battery-powered versions. This type of crimper is applied to low-voltage, network and telephony, and CATV applications, although battery crimpers typically are not used for network and CATV applications.”

Scirbona believes multifunction tools can make quality crimps. 

“There are many sizes and shapes of tools that can make RF45 or RJ 11 and RJ12, and also cut cable and strip jackets,” he said. “A single, crimp-only tool is best used in scenarios where only crimping one type of connector will be used. This tends to be a more assembly-line-type application.”

Ray Froude, senior product manager IEI-IC/MRO at Panduit, Tinley Park, Ill., observed that manual crimpers have become more refined and simplified.

“Traditionally, terminal crimping applications have seen more manual hand crimpers than the larger lug crimping applications,” he said. “This is simply due to the size of the terminal compared to the lug.”

But overall interest and usage of battery-powered tools increases every year.

“The portability, flexibility, increased battery power and overall ease of acceptance in the marketplace are a great combination for battery-powered crimpers,” Froude said. “And there is an optimal point between manual and benchtop crimping. The costs are typically 30% of a benchtop solution, and it is easily scalable to fit the needs of business models.”

When it comes to different applications, tools are broken down to crimp size ranges, Froude said. Using a large tool on small wire can overcrimp, which can cause overheating and premature wear. 

Froude said there are several factors to consider when selecting the right crimping tool.

“When choosing products like wire, lug, die and tools, there are many considerations,” he said. “The first is the wire and lug combination. It is important to choose the type of lug and wire based on the intended application. The next consideration is how the wire and lug will be crimped. To do this, consider whether the project is in a high-, medium- or low-usage environment. A high-usage, low-mix environment indicates a benchtop.”

It is very important to understand the recommended die and tool combination for the wire and lug that a user chooses.

Header image: Milwaukee M18 Force Logic 6T pistol utility crimper

About The Author

GRIFFIN, a construction journalist from Oklahoma City, can be reached at [email protected].





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