How to Buy a Power Impact Driver

Milwaukee 2650-21
A typical impact driver
A power impact driver is a power tool often used for tightening and loosening fasteners (bolts and nuts). Power impact drivers are capable of delivering a strong, sudden rotational and downward force and the direction of rotation can also be reversed for situations where screws have to be tightened with torque greater than a screwdriver can provide. An example impact driver is shown in the picture to the left.

There are many brands and models of power impact drivers out there on the market. If you only use the tool occasionally, a low-cost (or budget type that costs below $100) impact driver could be enough. Here’s a list of items that can help you buy the right power impact driver:

1. What’s the driver’s max torque?

One of the first things your will want to know is the maximum torque provided by the driver. The higher the torque, the more heavy duty tasks the driver will be able to complete.

The torque is expressed in terms of inch/pounds (in/lbs). A driver that provides around 1,000 in/lbs will be suitable for most purposes including driving deck screws and floor screws.

More powerful models will of course add value, but 900-1,000 in/lbs will be enough in almost any case.

2. What’s the maximum RPM?

The RPM values will be important as they will determine how fast the tool can drive. Most models will provide RPM levels of about 2,400-2,600.

You should know that RPM doesn’t affect the power or performance of the driver per se. But it affects productivity since driving faster will allow the users to get more work done in less time.

3. How many speed options? Is there a variable speed trigger?

In addition to maximum speed levels, you will also want to know if there are multiple speed options and variable speed trigger. Variable speed options offer maximum control so that users can use different speeds on different materials to prevent damages, etc.

4. How many volts is the battery?

Most models come with 12 to 18V batteries. 18V models are of course more heavy-duty type models (they offer the highest amount of power, provided that the torque/RPM values are up to par), but 12V models can get a lot of work done.

5. How many batteries are included?

Some drivers are sold as bare-tools without batteries. Most reputable brands use interchangeable batteries these days, so if the user has another tool from the same brand, they most likely will be able to use the same battery with the driver (if it has the same voltage of course).

On the other hand, some units come with 2 batteries, which is a big convenience for all users. They can charge one battery while using the other, then switch them over and continue to work without

6. How long does the battery last?

Another important factor that affects productivity is the battery charge. If users have to charge the battery after using the driver for a few minutes, it will be a big turn off.

Fortunately, most decent models will not have this problem as the batteries will last for a long period.

7. How long does it take for the battery to recharge?

This goes hand in hand with the previous point. If the batteries take too long to charge (and if there is no spare battery provided with the unit), you will not want to buy that model (unless it’s superb in every other aspect).

Again, most models come with smart chargers that can fully charge the batteries in 30 minutes and even offer the ability to half-charge the batteries (you can charge the battery for 5-15 minutes and still use it even if it’s not fully charged).

8. Is the driver compact and lightweight?

Most reputable manufacturers are currently focusing on creating more compact and lightweight drivers that offer maximum ergonomics. If the driver you intend to buy is compact in design, it will allow you to work in tight spaces that cannot be reached with bulky units.

The lightweight design is also very important, since a light driver will allow you to work for extended periods of time without too much fatigue. More working time means more work done in less time and is a big plus for professionals and amateur DIY’ers alike.

9. What’s the chuck size? Is it easy to insert and remove bits?

There are different chuck sizes used in drivers; the most common are 3/8” and ½”. The half inch models are considered heavy duty models and generally preferred by most.

And it is also important that the bits are easy to remove and change. Some models offer keyless chucks for toolless and easy bit removal.

10. Is there a battery indicator?

Some models have battery charge indicators that show the user how much charge is left and warn them when it’s time to recharge. This is a handy feature to have that further adds to the value and effectiveness of the driver.

11. Is there a built-in LED light?

Some models have built-in LED lights that illuminate the spot the user is working on. This can be very handy, especially when working on darkened corners and such.

Related information:

How to Choose the Best Cordless Drill