Also known as hand operated pneumatic tools, an air hammer is a versatile tool powered by an air compressor that can take a few different attachments, which leads to another name it is known for – the air chisel.
It’s a tool that can take on a wide variety of demolishing and stripping jobs, making it incredibly handy for renovations and other DIY projects around the house.
In the garage, the air hammer or air chisel is an indispensable aid to peening solid rivets, popping out CV joints, and other disassembly jobs that are simply too difficult to do by hand.
How To Choose which Air Hammer is Right For You
Handheld air hammers are very simple tools, all things considered. There is the barrel that can take one from a wide array of tool attachments, which is connected to a hand grip with a switch that the barrel is pointed at a right angle.
This form factor, common in other power tools like the drill and the nail gun, makes it easy for anybody with experience using other tools to pick up an air hammer and start using it.
Since there is just one basic air hammer type to choose from, your consideration basically boils down to the size of the job you need to do with your air hammer.
Keep in mind that most air hammers/chisels require around 4 cfm of airflow to operate on a continuous basis.
I would recommend using a compressor that can pump out AT LEAST that much, although more is better. Larger air tanks will also help to store the amount of air that is needed to run these.
To give you a better perspective, the pneumatic jackhammer, that can raise quite a racket as maintenance workers use them to break up roads and sidewalks, is a bigger (and noisier) form of the handheld air hammer.
There are also industrial-sized air hammers used in forges and welding plants that can shape and compress solid metal against a fixed anvil plate.
For most metal-working and demo/renovation type of tasks, however, most people will find that the basic handheld air hammer will serve them well for most jobs, provided they come with the right attachments and the air compressor is up to the task.
What Do You Need an Air Hammer For?
When considering the size and capacity of the air hammer you are planning to buy, consider the job that you will be using them for.
Air hammers, like rotary tools and oscillating tools, are only as useful as the attachments you end up using with them.
You can use air hammers to do a wide array of jobs
- Metalworking shops use air hammers to cut and shape metal. Air hammers are used to flatten, shape and cut most metals from thin aircraft-grade aluminum, copper, to other materials like 10-gauge structural steel. They are also used to deburr and smooth metal as well.
- Garage shops use air chisels to free frozen nuts, cut exhaust pipes, break shock absorber fasteners and to split ball joints and rubber bushings.
- Woodworking and stoneworking shops also use air hammers to speed up chiseling and carving jobs on wood and stone, as well.
- On the jobsite, air hammers can be used for a wide variety of jobs but usually are used for removing material like tile, cement, mortar, etc.
Depending on the job that you need an air hammer for, there is a wide range of attachments suitable for most models you can choose from.
Most air hammer attachments are universal and attachments from different manufacturers will usually fit other manufacturers' tools.
Features to Look For In Air Hammers
Air hammers are simple, straightforward tools that do not come with a lot of superfluous features – the air pressure operates an oscillating piston and that’s about it.
That said, there are a couple of points you can look for when comparing different air hammers.
- Ergonomic handles and vibration control features can take off some of the impact stress from your hands when using the air hammer.
- Aluminum or alloy housing keeps the tool relatively lightweight while remaining strong and durable.
- Different stroke lengths, BPM (blows per min.) and barrel shaft lengths are also something to consider when looking at different air hammers.
- Gradual progressive triggers not only give you more control over the speed of the air hammer, but they can also make it harder for the tool to be accidentally switched on.
The added control and safety of a progressive trigger makes this feature a must-have, especially for more heavy-duty units with longer barrels. - Quick change tooling features let you switch between chisels and tools faster. Even better if the accessory change can be done without the help of tools.
- A good selection of chisels and attachments in a kit allows you use the tool right out of the box, without having to invest in a set of attachments first. Of course, the more chisels and the wider the variety, the better.
- A carrying case protects the tool from damage while in transport, while also keeping the included attachments organized at the same time.
How To Compare Air Hammers
Comparing air hammers comes down to picking one with enough power to do the job you need it to do, and then some.
Light air hammers are well suited for cutting sheet metal and doing fine chiseling, while you will generally turn to the more heavy duty air hammers for automotive work.
Power
The power of the air hammer is usually indicated in the air consumption it will draw from the air compressor, and is given in Cubic Feet per Minute (cfm).
The more powerful the air hammer, the more air it will consume and the higher the average cfm figure it will have.
Generally, longer and more powerful air hammers will draw anywhere between 3 cfm for low impact applications, to up to 13 cfm for maximum hitting power.
Most air hammers, regardless of cfm, will require a continuous pressure of 90 pounds per square inch (psi) to work reliably.
Compare the cfm and psi figures of the air hammer you are considering with the air compressor, and make sure that they are compatible.
Size and Stroke Length
Stroke length is the distance the piston travels with each cycle, and this figure is usually given in terms of inches.
A typical, medium-duty air hammer will have a stroke length of 2-5/8 inches and can go up to 3 inches.
The longer the stroke length, the higher the velocity that the piston can achieve at the end of one stroke cycle, and the more power it can deliver to the chisel.
To accommodate pistons with a certain stroke length, an air hammer can have a short barrel, a medium barrel, or a long barrel.
Short barreled air hammers with low cfm are suitable for light work that require dexterity and control rather than sheer power, such as cutting through sheet metal and body panels.
Long barreled air hammers, on the other hand, are better suited for more demanding tasks like hammering stakes and loosening stuck nuts.
The size of the air hammer can also refer to the diameter of the chisel shank and the bore, which dictates which types of chisel attachments it can take.
Shank openings are typically in the 0.4-inch range, while bore diameters are in the 3/4 inch or thereabouts.
Keep in mind that manufacturers will usually stick to their tool specs, which may or may not be compatible with universal tool dimensions.
Attachments
Most air hammers come with a set of attachments like chisels and shaping tools.
Good brands will typically have five or more chisels included as a set, and these will have their own organizer in the carrying case.
Pay attention to the recommended hose diameter or inlet diameter of the air hammer, as well, to make sure it is compatible with your air compressor hose setup.
Speed
The speed of an air hammer is usually given in terms of Blows Per Minute (BPM). The faster the BPM, the quicker it gets the job done.
For tasks that include cutting and grinding, more BPM also translates to cleaner and more even cuts.
Decent air hammer models will have BPMS reaching to 2,000 or more, with some of the more powerful units capable of 3,000 BPM.
An air hammer model with a high BPM combined with a long stroke can be one of the most powerful units you can buy and usually the most expensive as well.
Weight and Noise
Lightweight air hammers can be as light as 3 pounds, while the more heavy duty models can be as heavy as 6 pounds. Do keep in mind that air hammers are loud – most units are rated at 90 decibels or more.
Exposure to noise as loud as 90 decibels for as long as 8 hours will likely result in hearing damage. Use hearing protection whenever possible, and take frequent breaks between tasks that use air hammers.
Air Hammer Usage, Maintenance, and Safety
Like most power tools, an air hammer is a powerful tool packed into a handy kit. Do not underestimate an air hammer – the pressure it can exert will easily cause serious harm, especially with a sharp chisel attached.
Check the user manual for the recommended air pressure level, and make sure to set your air compressor to match before connecting the air hammer.
Never use air pressure beyond the rated specs of the tool, as it can cause the air hammer to malfunction and even be damaged under load.
Regularly oiling the tool is also an important part of maintenance and will make the air hammer run a lot smoother.
Also check the air hose for debris or dust before connecting it to the air hammer.
Cleaning an air hose is usually easier than getting at the dust and debris stuck inside the air hammer, so it makes sense to look after the air hose first than to deal with issues later.
Always wear protective eye gear and gloves when working with air hammers, especially if you are cutting or chiseling metal or stone.
Never operate an air hammer in areas with suspended dust, combustible gas, or any area where a spark can trigger an explosion.
Insert the air connector and check for leaks. Some air hammer brands will have air connectors and adapters included with the kit – if your unit does not come with one, buy the right type of air connector first.
