Electric vs Air Impact Wrench. Which Is Better?

Impact wrenches are useful tools for both professionals and DIYer alike. But the tool was primarily used in factories and automotive shops with compressed air supply.
Thanks to electric tools, it’s been a while since many small garages and mechanic enthusiast can enjoy their benefits and even take them everywhere using cordless models.

In this article, I will compare the electric and air impact wrenches and give you an insight into the three types of impact wrenches available and their pros and cons so that you can choose the right one for you.

Air Impact Wrench

The first impact wrenches were pneumatic, and today they are still a great choice, mostly for professional use. They are powered by compressed air, and their maximum torque is given by their construction and air pressure measured in PSI (Pounds Per Square Inch).

These tools are not plug-and-play, you must have a good air compressor with a reasonable size tank to make them work properly, and you should have a strong air hose. If you have one of these and you have other air-powered tools, then it’s easy to add a pneumatic impact wrench to your tools’ arsenal.

There is a misconception about these impact guns being intrinsically more powerful than their electric counterparts. Their power (torque) is given by the tool’s size, construction, and the compressor’s and air supply. Today, there are surprisingly powerful electric impact wrenches available in tool stores.

Pros:

• They are cheaper than electric impact wrenches because they don’t have a motor or batteries, and their construction is simpler but strong.
• Because they don’t have as many parts as the electric impact wrenches, air impacts are compact and light, which makes them great for working in tight spaces and for prolonged use.
• With proper maintenance, they can last decades. All you need is a couple of drops of air tool oil applied on a regular basis.
• In case of damage, they are easy to repair than electric impact wrenches.
• They can work for hours without overheating. The continuous flow of air keeps the wane motor cool.
• They don’t run out of power as long as you have a suitable compressor.

Cons:

• You must have a powerful compressor with a big air tank to take the most of a pneumatic air gun and use it without interruptions due to air starvation. Even though you can plug other tools into a single compressor, a large-sized air compressor is expensive and require regular maintenance.
• The tool will always be plugged into a thick air hose, which is not as practical as using a cordless impact wrench or even a corded one where you can easily use a good-quality extension cord.
• You can have several ports to create working stations and be able to use your impact wrench on multiple sites. You should consider that a proper airline requires filters to keep humidity away, and they are not cheap.
• Pneumatic impact wrenches are noisier than their electric counterparts due to their characteristics and the compressor’s operation noise, although there are ways to make it quieter.
• Due to the nature of air impact wrenches, the triggers are not as sensitive as the electric versions. The torque output can usually be adjusted by a lever on the back and by adjusting the compressor’s output pressure.

Electric Impact Wrench (Corded)

Electric impact wrenches work plugged into the electric power source. They are usually bigger than air impact wrenches, their power levels depend on the brand and model, and they can be very practical for home and professional use.

The key advantage of the corded model is that it doesn’t require any additional investments and is ready to use right out of the box.

Pros

• They are portable and easy to use.
• You just have to plug them into a power outlet, and they are ready to work.
• They don’t depend on batteries or a compressor to work, so their power doesn’t fade as the batteries run out of power or the compressor’s tank gets out of air.
• Electric models are quieter than air impact wrenches.
• They usually have sensitive triggers, which allow for varying the power and rotation speed depending on how hard you press the trigger.
• Corded models are cheaper than cordless impact wrenches with the same power. Although they are more expensive than most pneumatic impact wrenches, you should factor in the cost of an air compressor.
• They don’t require much maintenance. Non-brushless models eventually require a replacement of the motor carbon brushes.

Cons

• The power cord is uncomfortable and limits its range to the length of the wire.
• Electric motors tend to overheat with extended use.
• They are harder to repair than air impact wrenches.
• Generally, electric impact wrenches have a shorter lifespan than air impacts.

That said, most professionals that I know are not using the corded version. In shops with compressed air supply, it makes sense to go with the pneumatic models since the bare tool is cheaper compared to its electric counterpart.

Cordless Impact Wrench (Battery Powered)

The evolution of powerful batteries helped to make cordless tools more and more popular. Impact wrenches are not an exception. They are getting more compact and powerful every day, with models that are near as powerful as the most powerful pneumatic and corded impact wrenches.

The portability and convenience make cordless impact wrenches highly effective for every kind of use.

However, they have their pros and cons too.

Pros:

• Easy to use. You just have to charge the battery and use them.
• Cordless power tools are extremely portable.
• They don’t need to be plugged into a compressor or a power outlet, providing a great deal of freedom of movement.
• They are the quietest type of impact wrench available.
• Most cordless models have a sensitive trigger that allows for regulating the rotation speed and power.
• They are great for both professional and DIY use.
• Lithium-Ion batteries are powerful and pretty light.
• The brushless models do not need much maintenance.

Cons:

• They lose output torque as the battery runs out of power.
• You may have to stop working to replace or recharge the battery.
• You need to invest more money to get the same power as an air or corded unit.
• The tool and the battery tend to overheat with extended use.
• Batteries have a limited lifetime. You will have to replace them eventually, which can be pretty expensive.
• Shorter life span. They don’t last as much as pneumatic impact wrenches. In the last 7 years, I had to replace my ½” cordless impact wrench twice while the air impact wrench is still going strong.
• They are hard and expensive to repair.
• Models with big batteries can be bulky and may be difficult to use in tight spaces.
• The battery adds extra weight, which can be a pain on your wrist if you are using the tool continuously for an extended period of time.

Which Tool Should You Use?

Go for Air Impact Wrench:

If you already have a good compressor and use other air-powered tools, or if you are setting up a garage or car repair shop where you plan to use other air tools.

A big compressor and tank with a powerful pneumatic impact wrench allow for doing heavy-duty jobs for long periods. For example, the ½” Ingersoll Rand 2235TiMAX has a maximum torque of 1,350 lb-ft and is compact enough to do any automotive work.

Electric (Corded) Impact Wrench:

Corded impact wrenches are an excellent choice when you are on a budget and need a reliable tool that you can unbox and use in the blink of an eye. No need to wait for the batteries to charge or invest in an air compressor.

Corded models also offer some degree of portability when you work indoors and on construction sites since it is easier to connect to the nearest plug point or use an extension cord than carrying around a portable air compressor.

Corded tools offer excellent average torque outputs and are wonderful for professional and home use. One of the most powerful corded impact wrenches available is the ½” Bauer 1882E-B, with an outstanding 1050 lb-ft of torque.

Get a Cordless Model:

When you need ultimate portability and don’t need to use the tool continuously.

Depending on the model and battery type, you will be able to do home and DIY work to professional heavy-duty work.

It’s incredible how some cordless products like the ½” Milwaukee M18 Fuel can deliver a massive 1,100 lb-ft of torque. (See the difference between M18 Fuel vs. non-fuel models).

The only downside of the most powerful cordless tools is the price. They are still pretty expensive compared with the air and corded impact wrenches.

Conclusion:

Cordless impact wrenches are getting more and more compact, powerful, and arrived to stay. Besides being practical, they are becoming a trend among tool aficionados. Pneumatic impact wrenches seem to be out fashioned or only advisable for extremely heavy-duty professional and quasi-industrial work; however, they are far from being obsolete, and they are also evolving.

Last but not least, corded impact wrenches are in the middle of both technologies and are practical and affordable. I have been using one for years, and it was very reliable for daily car repair shop use.

I think that it is clear that you won’t be able to efficiently make a pneumatic impact wrench using a small home compressor. If you do not have a decent size compressor, then going for an electric or a cordless impact wrench is a sensible choice for your budget. Ultimately it depends on your personal taste and your type of work, bearing in mind whether running out of battery is an option for you.