Before impact drivers, DIY enthusiasts and professionals had two options for power driving: the standard cordless drill and the impact wrench.
Then, drills were perfect for driving, drilling, and fastening in small projects. But, when woodworkers required more power, the impact driver became the go-to.
Eventually, the impact driver made its way to the market.
It had a more compact design that delivered more torque than a drill and was more convenient than a drill.
So, in this article, we will be focusing on the differences between the impact driver and the impact wrench.
Before we begin, let’s look at a brief overview of the two impactful tools (pun intended).
What Is an Impact Driver?
An impact driver is a powerful tool that delivers high torque through rotational force. The device can provide strong and repeated power for the driving and fastening of large screws and bolts. Even if the impact driver can handle basic drilling projects, I wouldn’t recommend it since it’s ideal for more robust projects.
What is an Impact Wrench?
Impact wrenches deliver much more power than the impact driver. First, imagine trying to loosen a big tough bolt with a regular socket wrench. Now imagine hitting the wrench with a hammer to apply percussive torque to loosen the bolt. That’s precisely what the impact wrench does. It hammers against the output shaft, which produces a total amount of torque.
Difference Between the Impact Wrench and Impact Driver
Most people confuse the impact wrench and the impact driver, and such mistakes are inevitable. The tools have many similarities that make it difficult to differentiate them.
However, the functions make them different. So, I’ll use the following categories to tell the difference between both tools properly.
One significant aspect that makes the two tools different is the driving style. The impact wrench primarily uses a square drive that allows you to attach a socket. You can also find 7/16-inch hex impact wrenches (used mainly by utility workers). On the other hand, impact drivers use a ¼-inch hex shank that only accepts ¼-inch hex shank bits.
Impact drivers have different styles, sizes, and performance levels. However, all impact driver designs feature only the 1/4-inch hex collet. Besides the standard pistol grip design, you can also find pressure-driven palm designs and right-angle impact drivers.
In contrast, the impact wrench covers a broader range of performance levels and even has more specialty versions. For example, you’ll find that most small impact wrenches have a 1/4-inch square drive, while compact wrenches feature a 3/8-inch wrench.
For performance, the 1/2-inch impact wrench is the most common size you’ll find in the market; hence most woodworkers use the tool.
But, when you need more power, the 1 inch and 3/4-inch are the suitable drives for the job. These drives can deliver power on an industrial level—although experts with specializations may not need this heavy equipment tool.
Additionally, when looking to buy an impact wrench, always look out for the mid-torque and high-torque. With this, you’ll have a good idea of the power level, even though there’s no specific power level for impact wrenches.
If you’re a construction pro or weekend warrior, then a compact and mid-torque impact wrench will get the job done.
As a bonus, here’s an outline of the available impact wrench styles:
- Pistol grip
- Ratchet style (low-power style designed to replace hand-ratches)
- Right angle
- Utility impact wrench (features a 7/16-inch hex collet)
- Stubby (features a shorter head for access to tight spaces)
Most impact drivers produced today are cordless models with 12v, 18v, and 20v max batteries. Of course, you can also find corded models if that’s what you want, but cordless is the more common variation. It’s also not limited to the voltages previously mentioned, and you can also find other voltages.
The same goes for impact wrenches. The tool has both corded and cordless variations. But, the sound of the impact wrench heard from a mechanic’s workshop is the pneumatic impact wrench. While most DIYers or woodwork enthusiasts rely on cordless models, the mechanics and experts use air-powered models—although batteries are becoming more popular in automotive shops.
No doubt, pneumatic impact wrenches are less expensive than the standard impact wrench. However, you’d need to spend the extra cost to get an air compressor and hose—if you don’t have one.
Now, you can easily decide what impact tool you need through the driving styles. Usually, an impact driver specializes in screw driving. So, you use impact drivers when working with fasteners that require a driver bit like Torx, Phillips, and Square. You can also use the impact driver for drilling if you have the right drilling bit.
Meanwhile, the impact wrench is for applications that require hex head fasteners like bolts, nuts, and timber screws. So, you don’t need to insert bits—with wrenches. Instead, you use the socket to hold the fastener.
However, there are a few exceptions to these driving styles. For example, you can attach socket adapters and nut driver bits to an impact driver, turning it into mini-impact wrenches—handling hex head fasteners.
Also, some adapters come with features that make your impact wrench compatible with 1/4-inch bits. However, you should know that these adapters can limit your impact tool from handling multiple applications.
So, my advice is for you to go for an impact wrench—if you need one. It’s better than attaching adapters to an impact driver to convert them into mini-impact wrenches.
My reason is simple!
Using these adapters can overpower the fasteners and cause them to shear or break—over time.
Impact wrenches are more potent than impact drivers. Therefore, you can get more torque delivery from the impact wrench. Some impact drivers in the 18v/20v categories have proven to be more potent than compact wrenches. However, when you take compact wrenches out of the equation, you will get more power out of the impact wrench for most applications.
Impact drivers measure power in inch-pounds, while impact wrenches measure in foot-pounds. So, I will be converting the values in this section for better comparison. If you want to calculate it, simply divide your in-lbs value to convert it to ft-lbs, and multiply the ft-lbs value by 12 to convert it to in-lbs.
Some powerful impact drivers exceed 2000 in-lbs (167 ft-lbs) of torque. Plus, any impact driver with a torque delivery of over 1600 in-lbs (125 ft-lbs) is great for professional use.
On the other hand, impact wrenches have a starting torque delivery of 100 ft-lbs (1200 in-lbs) and can reach over 1000 ft-lbs (12,000 in-lbs) of torque.
An impact wrench that delivers 200 ft-lbs of torque most likely has all the power you need to change the tires of a passenger car. Likewise, an impact wrench with mid-torque delivery of about 400 ft-lbs will undoubtedly accomplish all the mechanic needs.
Speed is where the impact driver has an advantage over impact wrenches. Some of the best impact drivers have a max speed of 3600 RPM or more. On the other hand, an excellent cordless impact wrench has about 2000 RPM.
However, the story changes when you add the pneumatic impact wrench to the mix. The pneumatic impact wrench beats the advantage of the impact driver with a super-fast 8000 RPM or better. In a nutshell, impact drivers are faster than standard impact wrenches but slower than the pneumatic impact wrench.
Some impact wrenches have the same size as impact drivers because they have similar foundations. But, if you go beyond that, impact drivers are always lighter and more compact than impact wrenches—except for the pneumatic impact wrenches.
In the case of impact wrenches, the weight and size of the tool increase according to power levels. The size of the drive can also give you a hint on the size of the impact wrench. So, you can find 1/4-inch drivers on more compact models and 1/2-inch drives on high and mid-torque models. In contrast, 3/4-inch and 1-inch models will be on even larger models.
Both the impact driver and impact wrench use the hammer mechanism to deliver high torque impacts. However, you can find two different hammer mechanisms in impact wrenches and one in impact drivers.
The first impact wrench mechanism is quite common. The hammer can rotate and slide on a shaft with a spring attached. Also, there’s a steel ball on a ramp in between the hammer and the driving shaft. So, if the input shaft rotates before the hammer with enough torque, the spring will compress and lift the hammer away from the anvil.
What’s interesting about this mechanism is;
It uses the “dog teeth” mechanism on the bottom of the hammer and at the top of the anvil to deliver high-impact blows.
When you use the tool, the hammer rotates until it makes contact with the anvil’s dog teeth. When the hammer stops, the input shaft keeps turning, causing the ramp to lift the steel ball as well as the hammer. So, the hammer continues to spin—as long as its dog teeth aren’t in contact with the anvil.
Once the spring is released, the hammer rushes towards the anvil and creates a powerful impact. This process is repeated, delivering the effect every time the hammer meets the anvil.
The second mechanism is also common. Here, the hammer is fixed directly onto the input shaft. And there are no dog teeth on the hammer and anvil. Instead, there’s a pair of pins that act as clutches. Therefore, the hammer continues to accelerate and rotate freely.
When the spring compresses, the hammer gets lifted while rotating. Also, the ball ramps move the pins against a spring and extend them to the point where they hit the anvil and deliver the impact. Afterward, the spring decompresses and releases the hammer.
Meanwhile, the impact driver uses a heavy-duty spring for its mechanism. The spring compresses at every half turn and lifts the hammer away from the anvil. It also releases the hammer that creates a powerful force when it strikes the anvil. This process happens multiple times in a second (up to 56 impacts per second).
While the impact wrench mechanism is more suitable for releasing and tightening hex bolts and nuts, the impact driver is ideal for driving in screws and other fasteners.
An impact driver delivers high torque or rotational force—during operation. In addition, it provides a robust and repeated rotational hammering force—to tighten or loosen fasteners and drill holes into dense materials.
On the other hand, an impact wrench exerts much force for loosening or fastening sockets, not driving screws or fasteners. And it’s ideal for heavy-duty automotive and construction equipment work because of how powerful it is. In addition, impact wrenches specialize in loosening stubborn or rusty bolts.
Impact drivers feature a 1/4-inch hex socket that uses bits specially designed to handle the high power of the impact driver.
Impact wrenches feature a square drive that is compatible with socket adapters. You use these socket adapters to handle hex bolts and nuts.
When to Use An Impact Wrench Vs Impact Driver
Like I earlier stated, impact wrenches apply a lot of force for fastening or loosening sockets. But, if you want to drive screws or fasteners, the impact driver is your go-to.
Generally, impact wrenches are the perfect tool for automotive shops. However, impact wrenches also come in handy for large-scale woodworking.
With that said, a vast majority of homeowners or seasoned woodwork DIYers might never need an impact wrench. So, if you handle many homemade applications and light woodworking projects, you may never need an impact wrench.
However, you can still have it around to change the tires of your car. But you’d be spending a fortune to get one. So, you can stick to the 4-way lug wrench—if you have to get a wrench.
Impact drivers are way more practical for home and DIY use. They offer a more compact design than an impact wrench and more power than a cordless drill. Hence, they are more user-friendly.
Although you can tighten or loosen bolts by attaching a socket adapter to an impact driver, the impact wrench is made explicitly for this purpose. As a result, it offers a much greater level of torque delivery and power.
A standard impact driver’s torque delivery is around 110 ft-lbs. On the other hand, the regular impact wrench dishes out a potent 700 ft-lbs. That’s a massive difference in the power and torque of the impact driver and impact wrench.
In a nutshell, you don’t need the power level and torque from an impact wrench to drive screws and other fasteners, but for a 10-inch stubborn torque nut, you’re going to need that extra power and large square drive of the impact wrench to get the job done.
Generally, impact wrenches are more expensive than impact drivers. For example, the cheapest impact wrench costs about $125.82, while the most affordable impact driver costs about $37.24. Nonetheless, I recommend you go for quality over price and pick one that best meets your needs.
Best Impact Wrenches to Buy
Impact wrenches are necessary for professionals in fabrication shops or automotive garages. So, if you’re looking to buy an impact wrench, here’s a list of the models I recommend.
The Ingersoll-Rand 23 impact wrench offers excellent quality at an affordable price. It comes with a standard ½ inch square drive and dishes out up to 5000 in-lbs., of torque. But it’s a pneumatic wrench, so ensure you have an air compressor to run it.
The DeWalt DCF880HM2 comes with two 20V max (4.0), and the wrench dishes up to 1,800 in-lbs. of torque. Again, it isn’t a bad deal, but most recent impact drivers offer the same power.
Although the Porter-cable PCE211 isn’t as convenient as its cordless counterparts, it offers excellent value at a lower price. Also, it dishes out a massive 3000 in-lbs. of torque.
Best Impact Drivers
Here are some impact drivers I highly recommend;
The Milwaukee 2656-21 is one of the best impact drivers in the market. Plus, Milwaukee’s batteries are known as the best. They last long and charge super-fast.
The driver has a max torque delivery of 2,200 in-lbs. Add its comfortable and sleek design to the mix, and you have a fantastic tool at your disposal.
The Makita XDT111 offers a lesser performance than the Milwaukee 2656-21. But, overall, it has an attractive price and a max torque of 1,500 in-lbs.
Impact drivers and impact wrenches have a lot of differences and few things in common.
But, to sum things up, the impact wrench beats the impact driver in power, and heavy-duty tasks, while the impact driver wins in compatibility and speed.
The rule of thumb is to choose the impact tool that best fits your woodworking needs.
So, which is your favorite tool, impact wrench vs impact driver?
Please, feel free to air your views in the comments section.