High volume, low-pressure paint sprayers are ideal for a wide range of DIY projects. They use a large amount of air to spray paint at a lower pressure than conventional sprayers.
Lower pressures meant they cover smaller areas but they are much more efficient than conventional sprayers. The lower pressure means that less paint bounces back off the surface.
There is a huge range of HVLP paint sprayers on the market, and it can be unbelievably overwhelming trying to choose the correct one for your project.
Luckily for you, we’ve got 5 stellar tips that will help you shop smart and find the right HVLP sprayer for your needs.
1. Pressure
The major difference between HVLP sprayers and conventional air sprayers is the way pressure is used.
Conventional sprayers use the same air pressure at the gun inlet as at the air cap. The air is pushed through at the same pressure and expels paint at high pressure.
HVLP sprayers change the pressure as it reaches the air cap. Reasonably high-pressure air enters the gun at the inlet and is taken to the spray cap.
HVLP spray caps have larger holes than conventional sprayers which means that when the air reaches the cap, the pressure drops but the volume is still the same.
Think about what happens when you cover a tap spout. If you put your thumb over the exit you get a strong, but small spurt of water. When you remove your thumb you get a lot of water but the flow is weaker.
The same thing happens with HVLP spray guns. The pressure drops so the stream isn’t as powerful. However, the volume of air at the cap is still the same. It can’t just vanish.
You might wonder why bother having high-pressure enter the gun if it’s going to drop at the cap. Well, compressed air has a higher volume. It’s like stuffing a box with packing peanuts. If you just toss them in, you can fit fewer peanuts. If you squash them down you can add more.
Most HVLP sprayers tend to use 40-60 PSI at the inlet. The pressure at the cap is usually at 10psi.
Some HVLP sprayers have adjustable pressure knobs at the inlet. These allow you to increase the inlet pressure which in turn increases the volume at the cap.
It’s not a universal feature but can be used to make covering larger areas a bit quicker.
The key thing is that you check whether your gun does operate at 0.1-10 psi at the cap. If it goes above this, then it is not an HVLP gun. Instead, it is a conventional sprayer.
2. Capacity
The capacity of your HVLP sprayer refers to the amount of paint your sprayer can hold. Usually, paint is held in a cup on top of or below the gun.
The larger the cup capacity, the less often you’ll have to stop and fill up again. It saves you time overall and helps you get a more consistent and even coverage.
Depending on your project, you may need to compromise between cup capacity and the actual size of the cup. If you’re doing delicate work in a small space, a huge cup may get in the way.
1000ml is the average cup capacity. If you have a large job you can get a slightly larger cup of around 1200ml.
For smaller projects, there are guns with 750ml capacities and sometimes even smaller. The major benefit to these is that the gun is lighter and easier to maneuver.
3. Cups
It’s not just the capacity of the cup you need to think about. There are different cup configurations.
The first choice you’ll need to make is whether to choose a gun with a gravity-feed cup or an under the gun cup.
Gravity-feed cups sit on top of the gun. As the name suggests, they use gravity to get the paint into the gun. It’s a simple and efficient system that gets pretty much all of the paint into your gun.
The other great thing about these kinds of guns is that you have a bit more freedom in terms of your painting angles. You can point directly up, down, and along all the angles in between.
With under the gun cups, you can struggle to get the paint out depending on how much is left and how long the air tube is. It’s a bit like trying to get the last bit of liquid out of a spray bottle.
The issue with these cups is that they can be a bit unwieldy. The weight of the paint and cup up top can take some getting used to.
The other option, the under the gun cup is a bit more stable in the hand. You tend to get larger capacities with this kind of cup because it’s easier to manage the weight.
These kinds of guns are more widely available and are often cheaper. The issue is that they are less efficient as dregs often remain at the bottom of the cup.
The other thing you want to look for is a large opening. Filling the cup can get messy if the hole is small. Either you drip paint down the cup or you have to use a jug or funnel which then also requires clean up.
4. Nozzles and Spray Pattern
You may be purchasing your spray gun for a particular project or simply to expand your toolbox. Either way, your best option is to look for a spray gun with changeable nozzles.
Guns with changeable nozzles allow you to broaden or narrow the spray. This may be necessary for smaller or larger surfaces.
You may also need a different sized nozzle depending on the paint you’re using. Thinner paints can use narrower apertures while thicker paints like latex and chalk paints require wider apertures.
The nozzles will be listed by the size of the aperture in the nozzles. For latex paints you’ll need a nozzle of over 2.5mm otherwise you’ll need to water down the paint.
The spray pattern is determined by the orientation of the nozzle. Most guns allow you to twist the nozzle so that you can change whether the paint sprays horizontally, vertically, or in a more circular manner. This is ideal if you’re going to be using your sprayer for a range of projects.
5. Area Covered
You’re not going to want to spend hours trying to cover a large area with a spray gun that only does an inch a minute. You’ll never finish!
All spray guns are rated according to how much surface area they can cover in paint in a minute or how much paint they expel in a minute.
The units used for measuring the area covered is cubic feet per minute, also known as CFM. For most projects, a gun that can do 2.5CFM is more than adequate.
If the product listing mentions fl. oz. per minute it is a measure of how much paint it can spray. It’s less useful to know than the CFM but it does give you an indication of how powerful it is.
Conclusion
There you have it, all the key features you need to consider before buying your next HVLP paint sprayer!
Don’t forget that you’ll need to read up on how to prep and clean your spray gun after use. Keep an eye out for our articles on those topics!