Get the Job Done Sooner When Choosing the Right Air Compressor From Repco

What is the best air compressor to buy for you and what will you be using it for?

First off, you need to be honest with yourself and work out what your air compressor will be used for. Whilst we all wish to be spending hours in the workshop turning out concours quality restored cars, will the majority of work you do be topping up air in your tyres and inflating flat footballs?

There are air compressors suited for every application and buying the biggest is not always the best when you don’t need that air volume or pressure to be running air sanders, rattle guns and other high-volume air tools?

How much space do you have in your garage or workshop and how much do you want to tick off your neighbours?

Now that you have established what your compressor will be used for it is worth asking these questions as they are definitely another consideration when looking to get yourself an air compressor.

Whilst a smaller compressor will be easier to tuck away it won’t give you the volume or pressure of a larger air compressor unit. This means that a whole raft of air tools will struggle to work adequately or will require longer time between use as the tank pressurises.

When we refer to larger and smaller units these are usually divided into belt drive units as larger and direct drive as smaller. This will be discussed further

So why do you need to take your neighbours into consideration? The reality is the smaller your air compressor the more time it will be running based on what you are doing.

If using a small air compressor, these oil less, or direct drive units can make almost 100 decibels of noise which is the equivalent of heavy traffic or a powered lawn mower. So, if you are car mad and intent on using your air compressor at all hours of the night, it may pay to look for a belt drive air compressor as these will provide both larger amounts of air but also produce less noise to anger your neighbours.

Does it need to be portable?

Most air compressors for the home garage come equipped with wheels to make them portable. This means you can easily position them under a bench or wheel them to other areas such as if you are spray painting.

Larger 3 phase or commercial air compressors are usually bolted to the ground and are not designed to be moved easily. These larger units however have greater tank capacities which make them ideal for using air tools that consume large amounts of air such as palm sanders and grinders.

Always make sure your air compressor has adequate ventilation to avoid heat build-up and also to ensure it has sufficient air to function. Overheating is one of the leading causes of air compressor failure so both adequate ventilation and choosing the right size compressor helps limit run times and heat build-up.

How often would you use your air compressor?

For smaller jobs or for infrequent use, the vast majority of air compressors sold at your local Repco store would be sufficient.

Single piston type air compressor makes up the bulk of our air compressors range for their ease of use and operation. These single piston units range from a 1hp / 8 litre tank to a 2 or 2.5hp air compressor with a 40+ litre tank that will provide the volume and pressure to run a number of air tools. Even our largest single piston compressor would require longer pressurization time between use when using air tools that consume a large amount of air.

The difference that exists between a direct drive single piston air compressor and a belt drive air compressor is that there are fewer moving parts in a single piston configuration. These enable the unit to be cheaper, compact and suitable for a wider range of conditions. The trade off with a direct drive compressor is the noise and also heat generated when in operation. The direct drive configuration also limits the tank capacity as a belt drive unit will refill or pressurize a larger air tank quicker due to the larger belt driven motor.

Provided you are patient you can get away without needing a larger compressor or air tank if you are not intensely working on large projects.

So what specs are you looking for to maximise your air compressor purchase?

The first step in working out what size compressor is best is you need to work out how much air each of your air tools consume.

Below is a small summary of commonly used air tools and their approximate air usage. Bear in mind that air tools can be rated in both a CFM (Cubic Feet per Minute) and LPM (Litres Per Minute).

A simple calculation is 1 CFM equals approximately 30 LPM. All references are also at 90psi unless stated.

• Tyre inflator - 1-2 CFM / 30-60 LPM
• Air blow gun - 1-2 CFM / 30-60 LPM
• Degreaser gun – 2 CFM / 60 LPM
• Air stapler / brad nail guns - 2-3.5 CFM / 60-100 LPM
• Air Ratchets, Air Hammers, Air Drills – 4 CFM / 114 LPM
• HVLP Paint spray guns – 4 CFM / 114LPM at 40psi
• Air Die Grinder – 5+ CFM / 150+ LPM
• 1/2in Impact / Rattle gun - 5+ CFM / 150+ LPM
• Sand Blaster – 15+ CFM / 450 LPM at 150psi
• Air Palm Sander - 17 CFM / 500 LPM
• Air powered Grinder – 22 CFM / 650 LPM

When shopping for a compressor there are 2 specs you should focus on. The first is PSI which stands for Pounds per Square Inch. This is a measurement of the force of air that is coming out of the compressor. The second and most important measurement is CFM which stands for Cubic Feet per Minute and this shows the volume of air that comes out of your compressor.

The higher the CFM your air compressor is the better your air tools will function. Always aim to get the most CFM air volume on any air compressor you are buying as this will help you finish any job faster and easier.

As you can see, not all compressors are created equal and based on what you will use it for you can now set about choosing the right air compressor for you.

Small 1hp units / small capacity tank – Good for tyre inflation, short bursts of air through an air gun

Medium 2 -2.5hp units / 40+ litre tank size – Will do the bulk of home / garage jobs but will run out of puff over continued use. Can handle spray painting for short periods of time

Large 3+ hp units / 50+ litre tank size – Usually comes in a belt drive compressor configuration – Good for all air tools and longer periods of work / Spray painting.

Do Not Force Air Compressors

Especially with smaller capacity air compressors it is important to allow adequate time between the motor being active. This is called a duty cycle and your compressor will do a better, safer job and give you much better service if it’s used within the duty cycle for which it was designed. Duty cycle is the proportion of time during which the air compressor is operated. Basically, this means that for every three (3) minutes of operation, the air compressor must be left resting for one (1) minute; motor on for three (3) minutes, and then motor off for one (1) minute if the compressor has a 75% duty cycle.

Picking the right air fittings and air hose

Having the air tools ready and the air compressor at hand you are going to need a suitable air hose and fittings to make this package work.

The longer the hose and the smaller the diameter of your air hose the less air pressure your air tools will receive to do their job. This means that a half inch drive rattle gun may struggle for adequate air pressure if the supply is limited by the size of the hose.

By choosing a larger hose and larger fittings you can adjust the regulator on your air compressor so that your air tools receive their required air pressure and work effectively and efficiently.

Once you have chosen your air hose you also require suitable air hose connectors to join both the compressor to the air line and your air tool to the line. 1/4 inch is the standard for these fittings and the most common type of connector is a Nitto type connector which allows for easy coupling and uncoupling of your lines and tools. They come in both male and female configurations and naturally you will need two of each when the time comes to connect your compressor, air hose and air tools together.

Always follow the air compressor and air tool manufacturers' instructions for use, maintenance, and safety.

Now that you have some of the basics regarding features, specs and considerations for purchasing your new air compressor you can be sure to get the right one at Repco. Whether direct drive, belt drive, home use or industrial we have the range and options to suit.

At Repco we are all about providing the tools and equipment to make your next project as easy as possible. Stocking a great selection of air compressors, air tools, air hoses, air reels and connections we can outfit your garage or workshop to tackle any task.