There is something meditative about using a brush to paint or stain a furniture workpiece after you’ve worked hard to cut, join and assemble it. Soft, slow, smooth strokes with a good quality brush can be relaxing and result in a high-quality finish to your project.
But then there are times you want to add a little speed to the process; the cutting, joinery, and sanding were the meditative part, and now you just want to add some color to the finished product, whether paint or stain. This is where the spray gun comes in.
The choice of which type of spray gun is important and will be based on what you are spraying – both the workpiece and the paint/stain. For this article, we’ll be discussing latex paint and an HVLP spray gun. Perhaps in another article, we will discuss HVHP spray guns and oil-based paints.
What Is An HVLP Spray Gun?
High volume, low pressure (HVLP) spray guns, also called turbo-sprayers, are the spray gun of choice for professionals. They are not inexpensive, ranging between $50 – $250, but will pay for themselves after only a few uses.
For the woodworking hobbyist who does a lot of work around the house like furniture-making, window and door trim, baseboards, cabinets, and more, an HVLP spray gun is a good choice. They use a higher volume of paint at a lower air pressure, which will give you greater control over the paint application for an even spread while minimizing over-spray and splatter.
This will result in a more economical application of paint. HVLP spray guns are much more efficient than conventional spray guns and will deliver about 65% of the paint to your target workpiece. Additionally, while the lines of a conventional spray gun must be cleaned after each use, the HVLP spray gun doesn’t. When you’re done painting, you’re done.
HVLP spray guns atomize paint. When the paint enters the feed line from the paint basin and comes in contact with the air stream of the gun, the paint is broken down into tiny particles as it is sprayed through the gun’s nozzle.
Advantages of An HVLP Spray Gun
All aspects of this process are adjustable, giving great control over spray density and a significant advantage over conventional and airless spray guns. You are able to control the air flow and paint volume, thus controlling the pressure and spread of the paint. This is a more efficient delivery method for paint than conventional and airless spray guns.
Airless Paint Sprayers
Airless paint sprayers pump paint through their nozzles at very high pressure. The tip of the sprayer breaks up the paint into a fan pattern of paint droplets. The high pressure produces a high spray volume, making airless paint sprayers well suited for large projects like the walls of a room or an outdoor fence. Much time can be saved on those larger painting projects where control is less necessary.
They do not need to be connected to an air supply (an air compressor), making them more portable. They rely upon the high pressure to force paint through the tip and onto the surface being painted.
LPLV Paint Sprayers
Just a quick word about LPLV (low pressure, low volume) spray guns for comparison:
- HPLV spray guns use more CFM (cubic feet per minute) air supply than LPLV guns, so the choice of air compressor becomes important;
- HPLV spray guns can be supplied air from a turbine unit that has a series of fans producing a high volume of air at a low pressure, as well as supplied air from a traditional air compressor;
- LPLV spray guns atomize paint better than HPLV models, can spray faster and can present a better finish, all while requiring less CFM of air pressure.
LPLV spray guns range in price from about $35 and up and can be found both online and at large DIY stores and local hardware stores.
What Pressure Should I Use to Spray Latex Paint?
I suppose we ought to be clear that you can use an HVLP spray gun to spray latex paint. Latex paint is the most common house paint for interior use. It dries quickly, is environmentally safe, and presents little odor. While they are not designed to spray heavier bodied latex paints, that is not a major issue. We’ll get back to this in a moment.
For spraying latex paint, there are two pressures to keep in mind, depending on what you are painting:
- A 26 – 29 PSI is suggested for a base coat on the surface being painted;
- A clear coat is better served by a lower 2 – 3 PSI for better atomization (remember that from earlier?) and flow.
What Nozzle Size Should You Use For Latex Paint?
Paint manufacturers recommend a nozzle size of 1.8mm. However, for a gravity-fed HVLP spray gun (where the paint basin is above the air stream line, you would want something a little larger, in the range of 2.0mm, to get the paint flowing.
How Do You Thin Latex Paint For HVLP Spray Gun Use?
Latex paint is water-based, so it can be thinned with water. Add a half-cup of water per one gallon of latex paint and mix it well. For a smaller paint amount, an initial water addition of about 10% of the paint amount is a good starting point.
If the paint falls from your mixing stick in a steady stream, it will be thin enough to work well with your HVLP spray gun. Remember, though, that if it is too thin, you can simply add a little more paint to the mix.
We found some helpful and informative videos to demonstrate everything in this article:
As we’ve said many times in previous articles, the right tool for the right job. An HVLP spray gun is the right tool for smaller workpieces where control will produce the best results. These include furniture, indoor trim for windows and doors, and cabinets.
You’ve worked hard on your project to turn it out well, so use the right spray gun to give it that professional finish.
