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Choosing an Air Compressor for Painting Cars – What Size, Which Is Best?

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It doesn’t matter what skill level you have when it comes to painting cars, the key thing that matters is having an air compressor that is able to provide a sufficient flow of pressurized air for optimum results.

It’s essential to obtain a high-quality air compressor suitable for your car painting needs. Therefore, this guide will provide you with some of the best car painting air compressors available on the market along with a buyer’s guide!

Table of Contents

Choosing an Air Compressor for Painting Cars Buying Guide

When it comes to deciding which air compressor is best for you, it typically comes down to a number of factors that you must consider. Before getting into the best air compressors, I want to provide you with a better understanding of the considerations at hand so you know exactly what to look for. You should really give thought to these areas to ensure that you walk away with the best possible option for your requirements.

Airflow (CFM)

Probably the most important consideration when it comes to spray painting a car, and this will typically depend on the CFM requirement of the spray gun you intend to use. Spray painters require a large volume of air to be injected into the paint which creates atomization so that the paint breaks up. This volume is commonly known as SCFM (standard cubic feet per minute) or CFM (cubic feet per minute).

People often get confused over the role of CFM and believe that it is the PSI that determines how the paint breaks up but it’s not. When it comes to using air compressors for painting cars, CFM is an extremely critical factor to consider, and in most cases, is the element of an air compressor that you typically pay for.

Low CFM spray guns may only require between 4-6 CFM to operate effectively while quality HVLP (high volume low pressure) spray guns may require up to 20 CFM of pressurized air. Some conventional spray guns will require around 10-15 CFM, and these will typically offer a better paint break up than the lower CFM spray guns and so, you’ll have a far better finish. For more information visit our guides on What Is CFM and What Does CFM Mean on An Air Compressor? and SCFM vs CFM for Air Tools & Air Compressors.

If you’re wondering how to increase CFM on your air compressor, wea also have a detailed guide!

Pressure (PSI)

When it comes to the pressure, measured in PSI, it’s important to purchase a compressor suitable for the pressure requirements of your application. With spray painting cars, you will typically only be using around 15-45 PSI, and given that most air compressors are rated for 90 PSI and have maximum pressures above that, you’ll have no issues here.

The only thing I will add which is very important to remember, when you see a CFM rating of a compressor, it will typically be “x” CFM @ 90 PSI. But, you won’t be using the compressor at 90 PSI, and so, due to the inversely proportional relationship between PSI and CFM, if you reduce the operating pressure of the air compressor you will increase the CFM available – marginally and within certain bounds. More on this in our guide Best Ways To Increase CFM On Air Compressors.

Compressor Type

What type of compressor do you require for painting cars? Typically 2 stage compressors are advised to deliver sufficient CFM for painting. 2-stage compressors are able to produce roughly 4 CFM of air per horsepower of the compressor compared to single-stage compressors (those found in most hardware stores) only producing about 1 CFM per horsepower.

So if your spray gun requires greater amounts of CFM, you’re best off getting a 2-stage compressor if you can afford one. Needless to say, this doesn’t mean you can’t use a single-stage compressor, a lot of them available are more suitable for household uses and a lot more affordable. When comparing the two, in short, a single-stage compressor is better for small-scale projects and personal use while a two-stage air compressor is better for industrial use. For more information visit our 2 Stage Air Compressor Vs Single Stage guide!

If you’re using a low-demand spray gun then a smaller compressor will suit you just fine. Visit our What Size Air Compressor Do I Need For Spray Painting? guide for more information on which compressor suits which tool size.

Not only do you need to decide between a dual-stage and single-stage compressor, but you also then have options for different types of compressors. When it comes to compressors, the common designs include rotary screw air compressors and reciprocating air compressors.

Reciprocating air compressors are more efficient than rotary screw compressors in that they deliver more CFM per horsepower, but, rotary screw compressors require less maintenance in comparison. Reciprocating compressors will require close attention and maintenance on components like their cylinders and pistons, while rotary screw compressors may only need oil, oil filter, and oil separator checks!

If you are looking for an industrial-sized unit, reciprocating air compressors come at a slightly greater cost than rotary screw compressors, and for painting a car, you will probably want an oilless rather than an oil-lubricated system, which costs even more.

For smaller compressors, reciprocating compressors are the more affordable, they do not produce as much heat and are cooled by air at a lower horsepower. This often makes reciprocating air compressors the favorable choice for low HP compressors for painting cars.

Tank Size

Don’t be tricked into thinking you need an air compressor with high CFM and a large storage tank in order to paint a car because you don’t, you can successfully paint a car with a compressor of low HP, CFM, and a small tank. The job just may be more difficult and you’re more likely to run into problems with overspray.

A small compressor with a smaller gallon tank is likely to leave you with time where the compressor needs to catch up and refill the compressor’s tank so that you can continue spraying your car. This can lead to accidental overspray of adjacent panels or parts of the car that were painted before the compressor cut out. Of course, if you plan to color sand or buff the finish afterward then this shouldn’t be an issue to you but it’s important to be aware of.

Painting a car means that you probably intend to run your paint gun for a long period of time with little downtime, so a pancake compressor and a low CFM paint gun may cause you problems. With your tank emptying often, the compressor will be forced into running almost continuously, which means it will get hot, lose efficiency and also put out hot air which will have a lot of moisture in it.

Smaller tanks can also have issues with pressure fluctuations and you’ll have more of a variance in the pressure and flow of the paint, resulting in uneven coats. That’s why most people recommend tank sizes of 50 gallons for car painting, typically found in automotive shops. Furthermore, a 60-gallon air compressor to paint a car will offer you the capabilities to probably paint the whole vehicle in one pass without having to refill.

We have a guide on How Long Does It Take To Paint A Car? which includes the steps of painting a car, along with this awesome 12 minute step-by-step YouTube demonstration which will get you clued up!

Duty Cycle & Continuous vs Intermittent Use

Another important factor when buying an air compressor for painting a car is the duty cycle. You do not want to exceed the compressor’s recommended duty cycle, which is the maximum compressor pumping time during its working cycle. So for a compressor with a 50% duty cycle (which is very common) and a cycle of 1 hour, the compressor must rest for 30 minutes to ensure that the compressor doesn’t overheat and premature wear is avoided.

This is where a larger volume tank size comes in handy because the compressor can fill the tank and then rest as you use the stored air before needing to kick in and refill the tank when it drops to its cut-in pressure. You may want to consider purchasing a compressor that has a 100% duty cycle and is suitable for a continuous run. These compressors typically won’t need that big of a tank volume as you will be able to deliver the pressurized air to your spray painter continuously.

If you only wish to use your spray gun intermittently then a small compressor will do the job. Typical uses of a spray painting gun for cars in a non-assembly line setting will likely be far less than 50% of the time drawing its required CFM. For more information on compressor duty cycles, visit our guide here where continuous vs intermittent use is also described in greater detail!

Those are the 6 key considerations you must be aware of and understand when you are buying an air compressor for painting cars. The air hose length is another important consideration that shouldn’t be neglected. The longer the hose, the longer the distance the air has to travel to reach your spray gun and thus, the greater the pressure drop across the length. It’s generally advised to use a hose as short as feasibly possible!

Other things you may want to consider are the noise level of the compressor, its size and whether it is portable or not, how reliable it is, and whether it has the auto-stop/start function (cut-out and cut-in pressure switch settings).

If you’re just painting a panel on the car, then sure, you don’t need a large tank-sized, high-duty cycle continuous use compressor to do so. A small compressor with a low CFM and a low CFM tool will no doubt suffice for such a job!

If you want to minimize the noise levels measured in decibels (dB) then there are compressors available that are quite than others and may deliver between 50-60 dB compared to upwards of 90 dB. It’s possible that you travel a lot, or work from different stations, and so, you want a compressor that is small, compact, and capable of being moved around. In this case, you would prefer a compressor that isn’t so heavy and challenging to move around.

The reliability of the compressor is important so that you minimize the number of issues you encounter along your journey. You should aim to buy a compressor from a reliable brand that provides quality equipment and offer a good warranty policy in case something does go wrong.

Most air compressors will have the auto-stop/start function on their pressure switch, where you can pre-set the compressor to stop working at a certain pressure and kick back in at another. Allowing the compressor to rest during periods of use and limiting the motor wear.

That’s all the considerations, I will now proceed to provide you with the best air compressors for painting cars. Hopefully, this buying guide will enable you to select the right one for you!

Best Air Compressors for Painting Cars

I’m not going to tell you which of the following compressors is the outright BEST air compressor for painting cars because it typically depends on how you intend to use the machine. Each will bring its own advantages and disadvantages depending on the sheer volume of paint you intend to spray on your car (or cars).

Craftsman Pancake Air Compressor

Airflow @ 90 PSI: 2.6 CFM
Maximum Pressure: 150 PSI
Horsepower: 0.8 HP
Tank Size: 6 Gallon
Duty Cycle: 50%

Let’s start with the Craftsman CMEC6150K compressor. A small, compact, and extremely portable oil-free compressor. This compressor offers a maximum air pressure level of 150 PSI and can provide 2.6 CFM at 90 PSI making it without a doubt one of the top air compressors for small car painting jobs.

This compressor would struggle to keep up for bigger car painting jobs or spray guns that require greater CFM as its tank size is only 6 gallons and it has a duty cycle of 50%. If you are just spray painting panels or small sections on your car then a compressor this size would be perfect.

The compressor only weighs 32 lbs and has a clever handle system allowing you to easily maneuver this lightweight air compressor from one location to another. The compressor comes with a 13-piece kit that includes a 25-foot hose, tired gauge, and more!

Some reviews complain about the compressor being a bit noisy, which may be a concern for you! Otherwise, it comes with a 1-year warranty which makes it a great choice! Here’s a YouTube demonstration of painting a car with this Craftsman pancake compressor!

Advantages

  • Additional accessories
  • Lightweight
  • Oil-free
  • Portable

Disadvantages

  • Noise level
  • Small tank volume

California Air Tools Ultra-Quiet Air Compressor

Airflow @ 90 PSI: 5.3 CFM
Maximum Pressure: 125 PSI
Horsepower: 2 HP
Tank Size: 10 Gallon
Duty Cycle: 50%

The California Air Tools 10020C is a great air compressor for spray painting your car quietly. This compressor has a 2 HP motor that operates at 1680 RPM which helps keep the noise levels down, below 70 dB. The compressor is able to provide 5.3 CFM @ 90 PSI and 6.4 CFM @ 40 PSI with a maximum pressure level of 125 PSI.

It has an oil-free dual-piston pump which leads to less maintenance and costs. The CAT 10020C has a lifecycle of over 3000 hours compared to most similar compressors which have a lifecycle of around 500 hours. The 10-gallon air tank allows you to store more air and use the compressor for longer periods of use compared to the Craftsman pancake compressor.

The only downfall with this greater-sized tank is the weight, standing at 82 lbs. But, luckily the compressor is designed with wheels so that you can easily maneuver it from space to space.

Advantages

  • 10-gallon tank
  • Easy-to-use controls
  • Oil-free
  • Quiet

Disadvantages

  • Weight

DeWalt 20-Gallon Portable Air Compressor

Airflow @ 90 PSI: 5.7 CFM
Maximum Pressure: 155 PSI
Horsepower: 1.9 HP
Tank Size: 20 Gallon
Duty Cycle: 75%

This DeWalt DXCMPA1982054 portable air compressor offers up to 7 CFM @ 40 PSI and 5.7 CFM @ 90 PSI with a maximum pressure of 155 PSI make it an ideal choice for painting cars.

The twin-cylinder oil-lubricated pump (shipped with synthetic oil to use), 20-gallon tank, and 75% duty cycle allow you to store a great amount of air for use and run the compressor for 45 minutes within an hour cycle, great for spray painting a car. In theory, this should be enough time to operate for, or close to, the whole hour cycle as the 15 minutes where the compressor must idle, you can use the 20-gallons of stored compressed air.

The compressor has pneumatic wheels with a small footprint and a handle to allow for excellent mobility and transportation. DeWalt is a well-established brand that offers high-quality products. Additionally, the compressor comes with a 2-year warranty on the pump, and a 1-year warranty on all other components.

Advantages

  • 20-gallon tank
  • High-quality
  • High-duty cycle

Disadvantages

  • Oil-lubricated pump (Must add an oil-separator, filter or similar)
  • Weight (166 lbs)

NorthStar Electric Air Compressor

Airflow @ 90 PSI: 11.5 CFM
Maximum Pressure: 135 PSI
Horsepower: 3.7 HP
Tank Size: 60 Gallon
Duty Cycle: 75%

This Northstar 75711 stationary electric air compressor boasts a 60-gallon air tank and 11.5 CFM @ 90 PSI, along with its 75% duty cycle making it a great choice for painting a car. The only problem here is that the compressor is 228 lbs and is not by any means portable.

The single-stage 2-cylinder design offers low heat transfer between cylinders and is typically made for automotive and mechanical shops, but you may find some people with this type of compressor in their garage! The large capacity of its air tank allows users to run their air tools for an extensive period of time.

This compressor is oil-lubricated, has an oil sight glass for easy oil level inspection, and is shipped with suitable synthetic oil. The compressor’s motor runs at 3450 RPM and so produces high noise levels of 80 dB.

Advantages

  • 60-gallon tank
  • High CFM
  • High-duty cycle

Disadvantages

  • Oil-lubricated pump (Must add an oil-separator, filter or similar)
  • Heavy
  • Noisy
  • Stationary

Air Compressor Additional Components for Painting Cars

After selecting the best air compressor for painting your car, presuming you’ve already purchased your spray gun, but, if you haven’t yet then take a look at our What Size Air Compressor Do I Need For Spray Painting? guide for examples of small, medium, and large-sized spray painting guns. I have also picked out this useful YouTube demonstration that discusses various paint guns, HVLP and LVLP.

The next step is to consider what additional options or components you wish to add. A very common issue with spray painting is the moisture and oil content inside the air, which can significantly ruin the painting work on your car. They will create fish-eye-like splotches and moisture pockets on the design. Not only water moisture and oil, but other contaminants like debris or rust can be found in your airstream, and so it is necessary to introduce a filter to remove them.

For this reason, it may be of interest for you to insert an oil separator, water separator (typically available as an oil-water separator), a moisture trap, or some form of filter in your lines to deal with this issue and ensure that the air reaching your spray gun is of the highest quality possible so that the finish is immaculate. Typically the

Below are a few examples of these mentioned components, readily available on Amazon. We also have a How To Make A Homemade Water Separator For An Air Compressor and Why & How to Get Rid of Condensation & Moisture From Air System guides that may be of great help to you!

Oil-Water Separator

Moisture Trap

Filter

You may wish to also purchase a regulator and install it at the end of your compressor’s piping network or line, just before where the spray gun is attached. This can help ensure that the spray gun is getting the correct pressure for its operation. In most cases, you will run the compressor at its advised working pressure of around 90-100 psi with its preset cut-in and cut-out pressures and then dial down the pressure right at the end of the line with a regulator to your required pressure.

This can help reduce any fluctuations and loss of pressure from the air traveling down the lines. For instance, if the air compressor is regulated to release air at say 30 PSI (which your spray gun requires), by the time it reaches the spray gun, the pressure could’ve dropped below 30 PSI and the spray gun may not work as efficiently as it could.

Another option is to insert a filter-regulator combination unit! Satisfying both your needs just before the air enters your spray gun. Below are examples of a regulator and a filter regulator combination unit readily available on Amazon.

Regulator

Filter Regulator

Depending on the size of your system, and this is typically aimed at industrial size compressors in automotive shops, it may be necessary to consider adding a 2 or 3 stage air dryer and have it connected to the pipeline running through your shop. Or even have an upgrade of this with a refrigerant dryer. The refrigerant dryer will be able to rapidly cool and then rewarm the air as it leaves the compressor, removing all the moisture in your compressed air lines when doing so.

This need is particularly important in small compressor shops that do not have long enough lengths of piping to allow the compressed air to travel before a 2 or 3 stage filter. The reason is that if the compressed air doesn’t have a sufficient length of pipe to travel down before reaching any regular air filter, the filter will not be able to properly remove moisture from your compressed air fast enough.

FAQs (Frequently Asked Questions)

What size air compressor do I need to paint a car?

This depends on the size of your job, are you painting a whole car or are you just spray painting a few panels? For the latter, any small size compressor should suffice because you won’t need continuous airflow. If you wish to spray paint a whole car, you may want a bigger compressor with a larger tank volume, CFM output, and a high duty cycle. It’s possible to use a smaller compressor to paint the car, but expect to work intermittently and have a lot of breaks throughout, to allow the compressor to keep up with the demand.

Can you paint a car with a 30-gallon air compressor?

Yes, you can paint a car with most compressors. The volume of a 30-gallon compressor may enable you to only have to stop spraying and refill the tank once, for you to complete the full paintwork on the car.

How many CFM do I need to paint a car?

This depends on the spray gun you have, or intend to purchase. You typically need to have a compressor that can provide the spray gun with its required CFM. Low CFM spray guns only require around 4-6 CFM to operate effectively while quality HVLP (high volume low pressure) spray guns will require upwards of 20 CFM of pressurized air. Some conventional and common spray guns will require around 10-15 CFM. The conventional guns offer a far improved quality finish as they break up the paint better than the lower CFM spray guns.

Can you paint a car with a single-stage air compressor?

Yes absolutely, if you find a single-stage compressor with sufficient CFM capabilities and a good size storage tank then you will have no issues spray painting a car. 2-stage compressors tend to be more popular, especially in automotive shops, but they’re industrial-sized. It’s far easier to pick up a smaller portable single-stage compressor that will allow you to complete your car painting!

Additional CFM reading:

What size air compressor:


If you have any questions regarding choosing an air compressor for painting cars, please leave a comment below, with a photo if applicable, so that someone can help you!

By Aidan Weeks

A passionate Mechanical Engineer with endless enthusiasm for fluid power - building off the back of over 18 years of high quality contribution and discussion stimulated by Bill Wade here at About Air Compressors. With both practical and theoretical experience in pneumatics and hydraulics, I'm putting my knowledge to work - and working my grey-matter through my research, assistance and publishing work here at About Air Compressors. Feel free to reach out any time! P.S. A HUGE shout out to Doug who really offers such great value to all visitors to About Air Compressors - once again, feeling like I'm standing on the shoulders of GIANTS by getting to work alongside such a great community

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