Why You Should Own an Impact Driver

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Impact drivers are among the most inexpensive tools you can buy that will instantly improve your DIY life. I waited years before purchasing an impact driver and immediately regretted not buying one sooner. Don’t be me—get one now.

Many people skip buying an impact driver when they learn that a power drill does everything an impact driver does and more. After all, a power drill can drill holes (it’s right there in the name) and drive screws. That’s why home center stores typically call the tool a power drill/driver.

Impact drivers, on the other hand, can only drive fasteners (like screws, lag bolts or lag screws). But once you understand what an impact driver is and how it works, you’ll want to own one.

What is an Impact Driver?

An impact driver is a tool made specifically for driving fasteners. At first glance, the body of an impact driver looks remarkably similar to a power drill, and you might confuse the two. But key differences make the impact driver better at its job than a power drill ever will be.

A power drill works by engaging a motor to turn the chuck holding your drill or screw bit. It’s simple and effective but doesn’t give you a great deal of torque.

An impact driver, on the other hand, contains additional components. If you take one apart, you’ll find a motor, a spring, a notched hammer, and a bar-shaped anvil. When you pull the trigger, the motor turns just like a drill.

When the impact driver encounters resistance (from the wood you’re screwing into for instance), the spring engages by pulling back. It then releases, which pushes the rotating hammer forward. That impacts and turns the anvil, which rotates the collet holding your driver bit. Here’s a video that shows the process in slow-motion.

When you use an impact driver, you can feel and hear the anvil strikes. It’s easy to think the impact is purely a downward force, but it’s more rotational than vertical. That leads to a great deal of torque without putting a lot of pressure on your arm, which is why impact drivers are better at driving screws than drills.