Cordless impact wrenches

When Milwaukee Tools introduced a cordless impact wrench nearly a decade ago, many had doubts about its usefulness. After all, it was in competition with pneumatic impact wrenches, which were fearsome for delivering power enough to loosen even rust-encrusted lugs nuts off of tractor rims.

So at the request of Successful Farming magazine, Milwaukee Electric provided several of its newly introduced cordless impact wrenches to two readers to try out. Mostly, their first reaction was one of skepticism. Kevin Kimberley, then farming at Maxwell, Iowa, called it a toy.

Six months later, the tool testers had a different reaction. Kimberley, who had his wrench stolen from the back of his pickup, was looking to buy a replacement. Darrell Geisler, who farms near Elkhart, Iowa, thought enough of the tool to consider putting one in each of his tractor's toolboxes.

Their previous opinion had changed with use. And since that time, impact wrenches have become a staple of most farmers' toolboxes.

What happened to the cordless impact wrench since its introduction is a massive expansion in the product's offering and power. You can choose from dozens of models that generate a wide range of voltages (12 volts up to 28 volts), in an array of anvil sizes (¼, ⅜, ½, and ¾ inch), and a toolbox full of features.

Power, price comparison

You may still be dubious of the value of a cordless impact wrench. And for good reason, as their price tags can be hefty. Besides, you may already own a pneumatic impact wrench and consider buying a cordless version as opulent. For comparison sake, I shopped around for ½-inch anvil impact wrenches. I selected an 18-volt Milwaukee cordless, a Milwaukee corded, and an Ingersoll Rand pneumatic tool to compare their torque, weight, and price. I found the following:

● Cordless: 450 ft. lbs., 6 lbs., $424.

● Corded: 300 ft. lbs., 6 lbs., $360.

● Pneumatic 725 ft. lbs., 4 lbs., $434.

The pneumatic tool won the comparison when it came to power (turning out more torque for about the same price as a cordless tool) and weight. The corded wrench was the cheapest, but not in the same league as the other tools.

So why go cordless? Portability. A cordless tool offers you one half to three quarters of the power of a pneumatic wrench, but you can use it in the middle of a field or on top of a grain leg.

Increasing popularity has inspired a great many manufacturers to jump into the cordless impact market, offering a wider variety of tools. This trend has spread the quality of the cordless impact product offering.

Factors to consider

To help guide you to the tool that is right for your shop and your pocketbook, consider these factors before buying.

● Battery type. Tools operating with nickel cadmium batteries are cheaper. But lithium-ion batteries, first introduced by Makita over five years ago, run longer (up to one third more time) between recharging. They also charge faster, are lighter (up to one half the weight), and offer a longer life (up to three times longer) than nickel cadmium units.

With the cost of replacement batteries running $50 to $75 or higher, longer life may make the extra cost of going with a lithium-ion-powered cordless tool worth its extra cost.

● Torque. The greatest difference between the tools shown in the chart above can be found in their torque output.

To a large extent, more expensive cordless impacts are more powerful thanks to stouter, more efficient motor and drivetrain design.

Less powerful tools would be adequate for doing light work around the shop. But if you need a wrench to loosen 1-inch rusted nuts on an implement in the field, go with a more powerful tool.

● Warranty. Like torque, warranty offerings vary greatly among manufacturers. As is generally the case, you get what you pay for. Consequently, a longer warranty often speaks to a better built tool that can handle tough work in rough conditions over a long life.

● Features. Many of the wrenches listed above came with Led lights, which are certainly a handy feature when doing work at night or in dark corners of a livestock barn.

Of greater value, however, is a feature like multispeed switch. This embellishment allows you to select a higher speed when doing high-volume work or a lower speed to conserve the battery length when in the field. 


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