Tools & Workshop

Choosing an Air Compressor Right For you

Here is a basic guide to LPM, FAD, PSI and HP

Air tools are some of the most useful tools in any home workshop. They provide better power to weight ratios, run cooler and are cheaper to purchase than their electrical counterparts. 240 volt air compressors work by compressing air using an electric motor to a pressure around one hundred and fifteen pounds per square inch. When you use your air tool, the compressed air is released and shoots out of the tank to power the tool. Once the pressure in that tank is lowered, the pump automatically begins re-pressurising the tank. You may also find that by using a compressor and air tools you can save money rather than buy the equivalent electrical option.

Here is a jobs Air Compressors can help with that will depend on LPM and size of tank:

  • Drilling
  • Tightening and loosening nuts and bolts
  • Inflating tyres
  • Painting
  • Sanding and polishing
  • Cleaning
  • Running large equipment

Supercheap Auto has a huge range of air compressors to choose from. Small quiet compressors for those small garages and basic workloads to a large workshop suitable compressor, plus more is avialable for order.

Choosing the right air compressor

To find out which tools match which air compressor you'll need to know the LPM requirements of the tool you’ll be using. LPM is the litres per minute of compressed air needed to run the air tool effectively. All Blackridge air tools come with this LPM reading on their packaging to make it easy to match the air tool to the compressor.

For example, the Blackridge 2hp compressor is perfect for basic home use. It can easily run brad nailers and air hammers as well as inflating tyres and other items. Larger air tools, such as impact wrenches, sanders and spray guns, require more air and a larger compressor such as the Blackridge 2.5hp high flow compressor. One step above are the belt driven compressors, designed for extended use, they are perfect for big jobs such as spray painting a car.

What size air compressor do I need?

In order to use air tools such as paint guns, impact wrenches, air nailers, and even tyre inflators, you’ll need a compressor to run everything. Since it’s the heart of any air tool setup, your compressor will need to be capable of meeting the requirements of your tools - which means that you need to buy one that’s the right size, and is powerful enough to do the job. Before you head to your local Supercheap Auto to buy a shiny new compressor, you’ll need to ask yourself a few questions in order to figure out what your needs are:

What sort of jobs will you use it for?

Are you going to be carrying out major projects, or just the odd job? Primarily automotive maintenance or some home construction? The more involved and varied the tasks you’ll need to run air tools for, the more likely you are to require a larger and more powerful compressor.

compressor

What types of air tools will you use?

Are you going to be sanding and painting? Or running things like wrenches and nailers? Generally speaking, tools that require a constant supply of air such as paint guns, sandblasters and grinders will need a compressor with a bigger tank. Also, the more power your tools need to put out, the more airflow that your compressor will need to provide them.

How much space do you have?

Usually, the more powerful your compressor, the larger it will be - so spare a thought as to how you intend to fit it into your workshop or garage. You might be able to stash your compressor away under a workbench, but when it’s running, your compressor will need to be free from any interference.

Where do you intend to use it?

If you only intend to work in one place, you can often run hoses of suitable length and keep your compressor in one spot. However, if you intend to work in other locations, be sure to consider the weight and portability of your compressor. Another thing to consider is the noise output of your compressor - the larger and more powerful they are, generally the louder they are, and the different drive systems will also impact the noise output. Once you have this information in mind, you’ll have a good idea of what size of air compressor is best for you.

What air tank size do I need?

Suitable air compressor tank sizes for the home workshop vary in size from around 5 litres all the way to 50 litres. The tank size simply determines how long you can run your air tools before the motor in the compressor has to turn back on to compress more air.

Because certain air tools such as grinders and sandblasters require a continuous flow of compressed air, they’ll need a larger tank than tools that operate in short bursts, such as nailers and impact wrenches. The fewer times the motor has to cycle on and off, the less heat it will generate, and the less wear it will sustain.

What is air tool and compressor LPM?

The amount of airflow an air compressor produces is One of the most important ratings that you’ll need to keep in mind when choosing your compressor. To find out which air compressor is capable of running which tools, you'll need to know the “LPM” requirements of the tools you’ll be using. LPM stands for litres per minute and refers to the amount of air that a compressor can output. Most air tools come with this LPM reading on their packaging to make it easy to match the air tool to the compressor.

What is FAD?

FAD stands for Free air delivery and is essentially another way of referring to the LPM of a compressor - remember that as long as the airflow coming out of your compressor is enough to power all the tools that you intend to run at the appropriate PSI rating to run them, you should have no trouble. A simple equation to use to figure out if a potential compressor will do the job, is to take the highest LPM rating of your current air tools and multiply that by 1.5 in order to give yourself a little wriggle room.

compressor

What is the HP rating on a compressor?

Horsepower (written as HP) is another common rating to determine the power of an air compressor. Whilst it isn’t as important as the LPM rating, it can give you a fair indication of how long the motor will take to fill the tank. A high horsepower engine on a smaller tank will only run for a short while before switching off (the motor’s duty cycle) but it will likely need to run more frequently as you empty the tank. Generally speaking, most compressors will have an appropriate motor matched to their air tank size, so you don’t really need to worry about HP ratings too much.

What is the PSI rating on a compressor?

The PSI rating refers to the air pressure the compressor generates inside the tank, measured in Pounds per Square Inch - sometimes the compressor will be rated in Bar as well. The higher this rating, the more “power” available to drive tools - which is especially important for tools like impact hammers and wrenches.

Belt drive vs Direct drive compressors

One of the major deciding factors when using a compressor at home is considering your neighbours, loved ones and anyone else around you. Simply put, all compressors can be noisy, however depending on the size and type, some types are less so than others - getting the right compressor may keep you in the good books if you need to run it late at night, or early on a Sunday morning. Of the two drive types, belt-driven compressors are generally quieter than their direct drive counterparts. This is because they are more powerful for their size so they rev lower - which has the added benefit of a lower operating temperature and a longer lifespan too. In short, belt drive compressors are generally better than direct drive compressors in practically every regard and are therefore a bit more expensive.

Using an air compressor

Once you’ve chosen the right air compressor, remember these few simple tips for easy use and maintenance.

  • Try to avoid extension leads. If you have to extend your compressors reach, it’s recommended to use a longer air hose.
  • Avoid using the air tool while the pump is operating to ensure the compressor stays within its recommended duty cycle. Wait until the pump has stopped before continuing work

Maintaining an air compressor

To keep your air compressor in running order, remember to clean condensation from the tank daily and the air filter weekly.