May 20, 2023

How to Use Locking Pliers

Gear-obsessed editors choose every product we review. We may earn commission if you buy from a link. Why Trust Us?

When you need clamping force, mobility and versatility, grab a pair of these.

Locking pliers are the indispensable hand tool that loosen bolts with stripped heads, clamp two pieces of metal together for any reason. They most often come into play whenever you’re trying to repair something and have to improvise a solution, sometimes a fairly unorthodox one. Own just one pair, and you’ll be convinced that you need another, and another, and before you know it you’ll have a set. While other pliers merely grip, these lock so tenaciously it's amazing what they’ll hold up, pull together, or twist off.

Read on for a bit of background on locking pliers, some standout models, and how you can best avail yourself of a pair.

We have genius blacksmith Bill Petersen, a Danish immigrant working in rural Nebraska, to thank for locking pliers. When he invented the plier locking mechanism in the 1920s, it's clear that he knew was on to something big. A decade later, his firm, Petersen Manufacturing, was busy turning out its patented locking Vise-Grip pliers by the hundreds. This is impressive when you consider that his success was unfolding in the depths of the Great Depression, when people had little money to spend and they were reluctant to part with what little they did have for a new form of hand tool that most had never seen before.

But as they say, seeing is believing. Before long, Petersen's company was pouring out the tools by the thousands, and then tens of thousands. Mechanics, farmers, welders, steam fitters, plumbers, and handy folks praised the tool for its powerful grip and versatility. Within two decades of introduction, the tool had achieved legendary status and become the subject of numerous testimonials, such as that of the railroad mechanic who lost his pair of pliers after he accidentally left them locked in place on a rail car that he was remodeling. He recovered them when that same car came in for service after having traveled 300,000 miles. The pliers were still locked where he had left them five years earlier.

I’ve kept a pair of Vise Grip 10WR pliers in my tool pouch for decades, and I once stashed them in a rusty old truck that I owned. Years ago, a tailpipe bracket rotted loose on that old Chevy just as I pulled into a train station parking lot. I know this sounds hard to believe, but as I surveyed the problem, I found a nearby wire coat hanger laying in the parking lot. I used the Vise-Grip pliers to convert the clothes hanger to a tailpipe hanger and still had enough time to catch my usual train. When tools save the day, people love them. And so it is with locking pliers.

Locking pliers are surprisingly sophisticated, relying on what mechanical engineers refer to as a four-bar linkage mechanism. In the case of these pliers, the top handle (and its adjustment screw) is one bar, the lower handle is the second bar, the linkage between the two handles is the third bar, and the pivoting lower jaw forms the fourth bar. The interaction of the two handles in conjunction with the adjustment screw's action against the linkage bar provides the necessary movement and a limit that will jamb the mechanism in place when you provide enough closing force on the handle. Here's a look at the four-bar linkage mechanism in action.

In a way, it's the tool's versatility (loosening, tightening, grabbing, twisting, or just clamping) that leaves beginners stumped about how to use it. It's right to ask how one tool can do all of that. If you’ve never used locking pliers or, sheepishly, you’re kind of mystified about how to use them, look no further. You begin with the pliers loose (that is, their jaws not gripping and the locking mechanism not engaged). You bring the handles together and keep squeezing while you twist the knurled locking knob. Some locking pliers have a ring, through which you can slide a screwdriver for increased twisting force.

Click the Open Gallery button below for a step-by-step breakdown of the locking mechanism in action.

Locking pliers are often used as compact clamps to hold a workpiece to a surface. Sure, you could use a woodworking clamp or C clamp for this, but those probably won't fit in your toolbox.

Other typical uses for locking pliers are to turn bolts and pipes loose or to hold them firmly in position so that you can more readily cut them off. Curved-jaw pliers are ideal for this.

People often overlook the fact that many locking pliers have a wire cutter at the base of their jaws. It's not particularly convenient, compared to a typical wire-cutting tool such as lineman's pliers. But they certainly work if you happen to be using locking pliers and encounter wire that needs snipping.

It's not unusual to find yourself in need of a vise when none is available. Two locking pliers can be arranged in an improvised vise that's very capable. So long as you have a sturdy work surface on which to clamp the pliers, even if it's just the top of a sawhorse, you’re good.

Removing finish nails fired by a cordless or pneumatic nailer can be troublesome because the fastener's head may snap off or a pry bar may have difficulty gripping the nail's small diameter. Of course, the fastener itself may snap in mid pull, leaving you with a tiny stump of a fastener. The same thing can happen when pulling a standard (hand-driven) finishing nail–the nail or its head may snap off as you pull it. Here, too, locking pliers can come to the rescue.

Sometimes you have to give a cold chisel or drift pin a hearty hit with a large ball peen hammer or even a small sledge. Other times, you may need to hit the chisel or drift in a place where you have little room to hold your hand. Holding the tool with locking pliers protects your mitts and can help you get access when you can't hold the tool.

Roy Berendsohn has worked for more than 25 years at Popular Mechanics, where he has written on carpentry, masonry, painting, plumbing, electrical, woodworking, blacksmithing, welding, lawn care, chainsaw use, and outdoor power equipment. When he's not working on his own house, he volunteers with Sovereign Grace Church doing home repair for families in rural, suburban and urban locations throughout central and southern New Jersey.

The Best Electric Kettles for Tea and Coffee

The 7 Best Ceiling Fans for Cooling

Champion's RV-Ready Portable Generator Is 38% Off

The 10 Best Portable Air Purifiers of 2023

The Best Camp Stoves For Cooking Outdoors

The Best At-Home Solutions for Wildfire Smoke

The Best Camping Tents for Any Base Camp

This Hart Leaf Blower Bundle Is 64% Off at Walmart

The Best Binoculars for Getting a Closer Look

The 7 Best Kayaks for Fishing and Floating

Craftsman Mechanic Tool Set Is 35% Off at Lowe's

The 9 Best Slim Wallets to Suit Any Style