When painting a car with a smaller compressor tank of about 15-20 gallons, you might have a chance at painting in one shot if you can adjust the pressure accordingly as it drops, although this will cause water to build up in the storage tank. You can drain the water from time to time to avoid damages.
However, with a small compressor, there are a number of limitations. Some of these limitations include running out of air while spraying continuously and low air volume, which prevents you from painting the entire car in a single shot.
Ideally, the recommended size for a paint gun air compressor is a 50-60 gallon tank with 5-6 horsepower that can put out the required pressure to run a spray gun non-stop and achieve a full car painting with a fine and smooth finish.
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What to look out for when choosing an air compressor to paint a car
There are various factors that determine the choice of air compressor suitable for car painting. From the size of work to be carried out to the kind of auto paint you want to achieve, there are bound to be different choices of air compressors.
However, there are some general factors that should always be examined before purchasing an air compressor to paint a car.
Size of the tank
The size of the tank of an air compressor for painting a car plays a big role in the general productivity of the project as well as the time taken. This is because, with a smaller storage tank, you will need to refill as often as you use it, probably several times while working. This can be a strain and struggle for large projects like a full-car coating. With smaller tanks, there is also the challenge of reduced pressure which affects the flow of the paint and results in uneven coats.
The ideal tank size for a more efficient painting job is 50-60 gallons. This is recommended in order to achieve an entire vehicle coating at one shot, without refilling.
CFM Rating
To break up paint into smaller particles that enable the process of spray painting of a car possible, a much higher CFM is needed. A higher volume of air will help achieve an evenly sprayed vehicle and uniform finish.
For an auto paint job, a high volume and low-pressure compressor are ideal. For the best car painting finish, choose an air compressor with a CFM of 14-18 per unit.
The only drawback is that it can be quite expensive. Also, if you only have a minor retouch to do on the car, then an air compressor with a lesser CFM rating will suffice.
Air pressure
Although it is evident that the CFM is a more important factor to consider than the air pressure when choosing an air compressor for painting cars, the pressure rating only determines the rate pressure with which the paint is delivered to the nozzle for spraying.
Generally, an air compressor with a minimum air pressure of 15 PSI will get the job done. However, for some other applications like clear coating, choose one high up to 20 to 25 PSI.
Horsepower
The horsepower of an air compressor refers to the amount of work that the compressor can carry out. This doesn’t imply that a higher horsepower equals a more efficient air compressor. However, it is advisable to purchase an air compressor with high horsepower to operate other tools.
Also for auto painting, it is recommended to buy an air compressor of about 10 hp.
What type of air compressor do I need for a paint gun?
To get your paint gun-running effectively, go for an air compressor of 15 PSI at the very least. However, for some other applications like a clear coat, 20 or 25 PSI is much more suitable.
For auto painting projects, go for an air compressor with a 10hp or higher for better efficiency.
What is LVLP spray gun?
LVLP is an acronym for Low Volume Low Pressure. LVLP is a great option when it comes to spray guns as they work better compared to HVLP spray guns because they operate at low pressure and a thin nozzle which allows only a low volume of paint to be let out of the spray gun.
It is also a good choice for those who are not ready to invest in a top-quality air compressor. Compared to HVLP spray guns, they produce only a few defects because they do not generate air bubbles which can happen as a result of high volume.
LVLP guns are generally cost-effective and can help you achieve a semi-professional paint job faster.
What is HVLP?
HVLP simply means High Volume Low Pressure which implies operating at a high volume of air and reduced pressure. Atomatization is not attained by high air pressure rather than volume of air. The high air pressure reduces the forward velocity and generates a softer spray as a result of this.
This is the same with HVLP paint spray guns. The paint coatings are atomized by using a high volume of air a reduced pressure.
In most cases, the pressure is reduced to a quarter of that used in other methods. This method reduces waste of material although more air volume is required than when using conventional sprayers.
Can I use an HVLP gun with an air compressor?
High volume low pressure commonly known as HVLP is one of the most popular spray guns in the market today. They are very powerful and provide controlled spray with just a little overspray.
While some HVLP guns can be used without an air compressor to run them, others require a large tank air compressor to run at all.
Can I paint my car with a 30-gallon air compressor?
It is advisable to always use an air compressor that has a capacity of 30 gallons of the tank.
This is ideal for running both home and residential projects. A 30-gallon air compressor will provide the volume of compressed air required to power a number of air tools including a paint sprayer, nail guns, rock drills, and more. It makes it much easier to apply the paint evenly and achieve a smooth finish.
Can I paint my car without a compressor?
There is an option for you to spray paint your car without using a compressor if you are dealing with the hurdle of finding the right air compressor for your spray paint. This requires you to use a handheld airless paint sprayer instead, it is ideal for painting materials of various thicknesses. They are also quite portable.
Do you need an air compressor for a paint sprayer?
Air sprayers operate by using pressurized air to paint a particular surface, producing an even and perfect finish. It is more ideal to use them when painting furniture.
While using an air paint spray, it is important to get a spray paint compressor that generates the airflow and air pressure needed to deliver a consistent paint flow and perfect finish.
How much CFM do I need to paint a car?
In most cases, the paint gun would come with a suggested CFM that would provide optimal operation. The most common rate of paint guns including high-end professional ones is above 12 CFM per shot. For paint guns to work and deliver steady output, they, therefore, require a compressor of over 12 CFM.
Can I paint a car with a 5-gallon air compressor?
It is advisable to purchase a 30-gallon storage tank air compressor to paint your car. This is preferable for larger projects like a complete vehicle coating.
Ideally, with a storage tank size of 60-gallons, you can paint your car from start to finish in one pass by pumping out enough CFM without needing a refill. Using smaller tanks might get the job done, but it will also lead to uneven coats at different places.