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Before we delve into the complex world of wrenches, let’s start at the beginning. An air impact wrench works on the principle of compressed air. It tends to store energy in a rotating mass and uses this energy in a sudden and intense manner when the button is pressed to deliver a high torque output via its shaft. For an interesting, slow motion perspective on how an impact wrench works, click here.
An air impact wrench, also called an air gun, impact gun, or torque gun, is preferred over manual labor because it makes the user’s task very efficient. People can easily use an impact wrench to remove or drive fasteners into the desired surface. The best thing about this tool is that it saves the user a lot of fatigue and makes the painstaking task of drilling and fastening nuts and bolts painless and efficient.
Air impact wrenches are also preferred because they are very simple to use. They can be operated with electricity, air compressors, or readily available batteries, depending on your personal preferences. While all the tasks performed by the air gun can be done manually, they shouldn’t be because of the risks involved. People who don’t use these impact wrenches run the danger of having bruised knuckles, disfigured fingers and, above all, exponentially increased frustration and rage levels. Thus, for your physical and emotional well-being, it is better to use an impact wrench because it does what any good machine should: making the user’s life simpler.
These impact wrenches are preferred over manual labor because they deliver high torque instantaneously. Speaking as someone who has worked on hundreds of Do It Yourself (DIY) projects, whenever I find myself unable to remove a tight bolt or a screw that just won’t stop slipping in my hands, I reach for my impact wrench. This device has made my life significantly easier and for that reason alone, I always recommend it to people who enthusiastically participate in home improvement projects.
Cordless Impact Wrench vs Driver
When one begins his search for the best battery-powered impact wrench, one word that keeps on popping up is ‘driver’. These drivers should never be confused with impact wrenches because they are two different entities. Granted, there is some functional overlap between these two products (such as employing a rotary hammering action to deliver sudden, rotational force), they aren’t essentially the same thing and differ from each other significantly.
The first point of difference between a torque gun and a driver is that air impact wrenches provide a steady downward force coupled with rotational hammering. This downward pressure appears to be fundamental in loosening stuck screws and bolts without damaging them. Another key difference is that a cordless electric impact driver typically has a ‘female’, quick release hex chuck, whereas most wrenches have a standard 1/2″ or 3/8″ square drive.
1/2″ vs. 3/8″
Now that you know the difference between an air impact wrench and a driver, you should understand that the wrench is the far superior tool due to its downward pressure. However, this doesn’t make the task of selecting the best impact wrench any easier because there are many different aspects which can make or break your project. One of these aspects is choosing between a 1/2″ and a 3/8″ impact gun. Now, the important point to understand here is that neither of these options is a bad choice; rather, they are both ideally suited for different tasks.
To know which wrench to use and when, we must look at these two options on the criteria of compatibility and power.
A half-inch impact gun will only be compatible with half-inch sockets. On the other hand, a three-eighth inch impact wrench will only work with its counterpart. Thus, when choosing between the two options solely based on the factor of compatibility, it is important to know what sort of tools you have in your tool kit and choose the impact wrench which is better suited to your arsenal.
A half-inch air impact wrench is typically stronger than its three-eight inch counterpart. Granted that the revolutions per minute (RPMs) of the 1/2″ impact wrench may not always be higher than the 3/8″ impact guns, the torque always is. Since torque is our chief indicator, we can directly say that half-inch impact wrenches are better when it comes to the power delivered. However, there is a trade-off too as high-power output means that these 1/2″ impact guns are bulkier and heavier than their 3/8″ counterparts.
What Powers an Air Impact Wrench?
After we have understood the complex issues of compatibility and power, we must understand another important criterion of selection: what powers the impact wrench? Based solely on the power source used, there are three different types of air impact wrenches.
1. Compressed Air – Compressed air powered impact wrenches are chiefly used by professional mechanics when fixing cars. The air tank is connected to the wrench and acts as the main power source. The air compressor helps the impact wrench to generate a lot of torque that makes it excellent for heavier jobs, which is ideal for mechanics as they work on heavy automotive equipment. Without an electrical source of power, air compression impact wrenches are relatively lightweight. However, the biggest drawback of compressed air impact wrenches is that you will need to have a tank of compressed air ready for it to work.
2. Electricity – Electricity is defined as the flow of charge in a particular direction. The discovery of electricity has redefined almost every aspect of our life. This fact holds true for air impact wrenches as well because electricity powered impact wrenches also provide a significant amount of torque. Electricity powered impact wrenches are ideally suited for small scale jobs such as home workshops. However, you will need a steady supply of electricity to run these types of impact wrenches. The biggest drawback of electricity powered impact gun is that they are not quite as strong as the impact wrenches that use compressed air. This is the main reason why they are not preferred for large scale projects.
3. Battery – Finally, there are some impact wrenches which use neither compressed air nor electricity to get power. Instead, they rely on utilizing battery power. Battery powered impact wrenches are cordless, which makes them very convenient to move around. In fact, the best feature of battery powered air wrenches is their incredible portability. However, one must make sure that the battery is fully charged so that the wrenches do not run out of power when they are in the middle of a job. Many users will buy an extra battery to keep on hand for when one loses its charge. This will prevent any gap in using the tool.
Important Characteristics to Consider
Before we can decide on the ultimate air impact wrench, we must first understand what makes an air impact wrench good. The following factors must be met in the best way they can for an impact wrench to be considered great.
1. Torque – Torque is defined as the rotating effect of force. Effectively, torque is what is needed to remove nuts and bolts faster, so torque ultimately controls the speed of the task at hand. Therefore, it is important to select those air impact wrenches that have a higher torque rating. The minimum torque rating one should settle for is 150 ft-lbs.
2. Weight – The weight of the air impact gun is also an important deciding factor because how heavy the impact wrench is can affect certain things like how tired your hand and arm get after prolonged usage. Weight is not that big a deal for relatively shorter projects, but if you are working on longer projects, a heavy impact wrench can cause a lot of fatigue and frustration.
3. Size – Ideally, the smaller the size of the air impact wrench, the better it is for prolonged usage. However, there is a trade-off because the smaller the device gets, the lesser torque it can produce. Even though this is not always the case, it is a good rule of thumb to remember.
4. No Load Speed – From an engineering standpoint, no load speed refers to the speed of rotation of the rotor of a device, when it is powering no load. In the case of an air impact wrench, no load speed is defined as how fast the wrench turns when it is not being used to unscrew nuts and bolts. Higher no load speeds will fasten screws and bolts more quickly, but sometimes a higher speed means lower torque. If you have to choose between higher speed and higher torque, it is better to go with the option that offers higher torque.
5. Drive size – We have already covered the two most commonly available options when it comes to driving size i.e. 1/2″ and 3/8″. Among the two of them, the more commonly used drive size is 1/2″ which works for almost all applications. On the other hand, the 3/8″ one is a smaller option which offers lesser torque than the 1/2″ drive wrench.
6. Ergonomics – Ergonomics refers to how comfortable a device is to hold in your hands. Ideally, it is better to select the impact wrench which is the easiest to hold and use, especially for longer periods of time. Comfortable grip materials are also important because they enable the user to take on longer jobs without any cramping or soreness.
7. Product Warranty – One of the most important features to consider is a product’s warranty. As it is an expensive item, it is important to find a wrench with a good warranty. Most manufacturers offer at least a one-year warranty, although you will find some that offer 2-year, 5-year and even longer warranties. Thus, it is wiser to select those wrenches that offer the longest warranty.
8. Torque Adjustment – Warranty is not the only feature that you should look for; another important feature is torque adjustment. This feature allows the user to adjust the amount of output torque that the impact wrench is providing. Thus, it is instrumental in preventing over-torquing or snapping a bolt’s head right off.
9. Impacts per Minute – Impacts per minute determine the effectiveness of an air impact wrench. A higher number of impacts per minute means the impact wrench can drive screws faster and will also be able to loosen the bolts that are held more tightly.
10. Power Regulator – Some models come with power regulators that allow the user to use the available power with more precision. This, in turn, allows the user of the wrench to complete his tasks with minimal effort. Not only that, but high precision means that these tasks are finished correctly as well.
11. Noise Levels – Air impact wrenches are well known for the noise that they produce (see NIOSH Power Tools Database for more info), which can prove to be an issue if you are working on a project in a densely populated area. Thus, it is important to select those air impact wrenches that produce the least amount of noise so that they can be used freely and without the worry of frustrating your neighbors. Remember, select those air impact wrenches that have noise suppression technology as it reduces the noise level significantly.
12. Budget – One of the most important things to consider before buying any air impact wrench is your budget. What good is it to find something that fits your needs perfectly but is ultimately out of your budget. Thus, it is important to always remember your financial constraints and buy a product that you can afford.
How to Use an Air Impact Wrench
The usage of an air impact wrench can be divided into three simple steps, which are outlined for you below:
Step 1: Assembly – Take out the instruction manual that came with your product and thoroughly study the figures that demonstrate how to assemble your product. This quick glance should suffice, and assembling your product from this point should prove to be no problem as these illustrations are quite descriptive. However, if you find yourself unable to comprehend the information written in your impact gun’s instruction manual, you can undoubtedly find an assembly video of your device on YouTube.
Step 2: Testing – After the product has been assembled, it is important to test it out in the field before you can use it on your actual project. Check the direction to which the air impact wrench is set. This can be done by lightly touching the trigger and observing which way it turns. You will notice a latch or knob somewhere on the side of the wrench which allows you to reverse the socket direction. If you want to loosen the connection, make sure it is counter-clockwise, and for tightening purposes, make sure it is clockwise.
Step 3: Speed Configuration – It is important to select the correct speed before using an air impact wrench. First, assign the desired speed using the dial or switch on the wrench. Once you are happy with the speed and torque settings, you can attach the correct size socket to the bit on the front of the wrench. Fix the socket bit on the wheel nut, and press the trigger on the air impact wrench. The nuts of the wheel should loosen nicely and you can easily take them off. Now your air impact wrench has been fully configured for safe usage on your projects.
As promised, this complete guide of the best air impact wrenches also includes a brief review of each wrench that stood out to us. We have also highlighted what tasks they should ideally be used for so that it is easier for you to find a product that best suits your needs.
1. Makita BTW450 Review
The Makita BTW450 is no doubt a specialty product for those users who need an impact wrench exclusively for larger jobs where big bolts need a motor that can effectively handle them. The best feature of the Makita BTW450 is that it has been optimized for prolonged use. It is intended for taking armor plates off a tank. It redlines at 1,600 RPMs with 3,900 inch-pounds worth of torque. It has a dial size of 1/2″ that works with impact-rated socket sets.
2. Craftsman 9-17562 Nextec Review
Among our list of powerful impact wrenches, we could not exclude this device even though it is technically an impact driver and not a true impact wrench. The Craftsman 9-17562 Nextec is not designed to work on a job from start to finish; rather, it should be treated as the go-to device for tighter spots and odd bolts. It houses an LED light because it is meant to be used in dark corners where other tools dare not tread. With 700 inch-pounds of torque on a reversible drill that only truly becomes a driver when in a tough spot, having this as a backup is never a bad idea.
3. Ingersoll Rand W7150-K2 Review
In the field of impact wrenches, Ingersoll Rand reigns supreme. Its products are undoubtedly the best in the market and offer great value for money. This is evident from the quality of its flagship cordless air impact wrench i.e. the Ingersoll Rand W7150-K2. Even though it costs significantly more than other impact wrenches on this list, it is also one of the best names in it. The W7150-K2 has 13,200 inch-pounds of nut-busting torque should you need it, but since the standard running tops out at 9,360 inch-pounds, you have got to push the overdrive to access this power. A soft-touch molded grip, heavy-duty construction, a steel case that is bombproof, and the IR logo on the side backed by its service and warranty mean that this is easily one of the most reliable air impact wrenches available on the market today.
4. Milwaukee 2453-20 M12 Fuel Review
The best feature of the 2453-20 M12 Fuel is its ergonomic handle and rubberized grip that wraps around the hilt of the M12 Fuel. This feature means that users can now work for hours without fatigue or stress setting in. For Milwaukee, the M12 Fuel is an advancement from its earlier works, and it has managed to add amperage hours to this generation for longer battery life without losing the 0-2,650 RPM speed. It’s all backed up by a brushless POWERSTATE motor that ensures seamless operation.
5. Bosch IDH182B Review
The Bosch IDH182B is a hybrid tool. Now we understand that most hybrid tools do two things badly instead of doing one thing well, which is why customers try to avoid them as much as possible. In this case, the roles have been reserved. The Bosch IDH182B can take both your 1/4-inch hex screwdriver bits and 1/2-inch impact socket drivers without the need for an adapter. The strange nose does sticks out a bit, but if you swap between sockets and screws on a regular basis, the added size and inconvenience is nothing compared to fetching a whole new tool. Moreover, the triple speed brushless motor goes from 400 to 1,650 inch-pounds offering as much as 2,800 RMPs.
6. Makita XWT02Z Review
Makita tools have been used by professional mechanics for a long time, chiefly because they offer incredible value for the money and are easy to operate. This happens to be the case for its XWT02Z model as well because for a small fee, you will have 2,520 inch-pounds worth of torque at your disposal. While not quite as small as other models launched by Makita, it clocks in at about 5.75-inch and weighs just under 4 lbs. When you factor in its glorious 4.0Ah batteries (that churn out hours and hours of runtime) and its efficiency into the equation, the Makita XWT02Z is clearly a wise choice for people looking for effectiveness and portability.
7. Dewalt DCF883 Review
The DCF883 20V from the masters of mobility i.e. Dewalt gives you 1,560 inch-pounds of torque. At first, this may seem far from astounding, but one must understand that this impact gun does this using a 3.4 lbs. package. Moreover, as this impact wrench has been made by Dewalt, you can be rest assured of its quality and portability. The DCF883 20V has a 3/8-inch hog ring anvil which enables rapid swapping that feels much more like a cordless drill. However, one of the biggest cons of this drill is that many consumers find it hard to purchase just the impact wrench itself, and they are often forced to purchase the entire kit instead – though we had no problems finding the DCF883 as a standalone product on Amazon at the time of writing.