What is an HVLP Spray Gun and When is it Right For Me?
What is an HVLP Spray Gun?
An HVLP Spray Gun is one of three primary Air spray gun styles. The other styles of spray guns include LVMP and Conventional. For an overview of all three check out this article.The term HVLP stands for High Volume Low Pressure and refers to the way that coating is atomized (broken into particles to create a fine finish). The pressure at the air cap of a spray gun determines how efficient it is at applying coating. The higher the efficiency of a spray gun the less paint that is wasted. HVLP Spray guns use a high volume of air at a low pressure (less than 10 PSI) which results in high transfer efficiency. The benefit of applying the coating at a low pressure is a higher transfer efficiency of about 65%, this is about twice as efficient as a conventional spray gun (about 35 – 40% efficient) and slightly more efficient than an LVMP spray gun (5-10%). The downside of using low pressure and a high volume of air are two main things. First, an HVLP gun will not atomize heavy bodied coatings well. If the coating is excessively viscous it will not atomize well with an HVLP Spray gun and can result in orange peel in your finish. Second, an HVLP spray gun will typically require more air than a conventional spray gun from your compressor. Although there are HVLP Spray guns that require lower volumes of air they typically will not atomize the coating as well as a higher CFM air cap.
Common coatings that will not work with HVLP Spray Guns include:
- Coal Tar
- Heavy bodied Industrial Enamels
Overview of HVLP Spray Guns Pros
- Transfer efficiency is higher than other air spray guns (about 65% efficient)
- You will not waste as much paint (up to %30 percent less paint waste)
- You will not have to change Spray Booth Filters as Much compared to if your using a conventional Spray Gun
- Provides a Fine Finish
- Approved by EPA for emissions reduction standards requirements
Overview of HVLP Spray Gun Cons
- Costs more (Typically a high quality HVLP spray gun will cost more than a conventional spray gun anywhere from $100 – $300 dollars more)
- Not able to spray heavy bodied coatings
Due to the challenge HVLP spray guns can have with certain coatings it is always recommended to refer to the Technical Data Sheet for Your Coating to see if HVLP is one of the recommended application methods.
Turbine Vs Air Spray HVLP Spray Guns
Turbine HVLP Spray Gun Pros and Cons
A turbine HVLP spray gun uses an independent turbine unit to provide the air for the HVLP Spray Gun to apply coating. The benefit to of the turbine driven HVLP Spray Gun is that it is portable and doesn’t require a seperate compressor which can be more affordable if you are just thinking about getting into spraying and will only need an HVLP Spray gun. However, if you plan on painting routinely the Turbine unit will limit you to an HVLP Spray gun and will not allow for the use of different types of spray guns. If you will use a variety of coatings or need to spray heavier coatings you will have greater versatility by buying a compressor and HVLP Spray Gun.
HVLP Air Spray Gun Pros and Cons
An HVLP Spray gun fed by a compressor will provide diversity and options of types of spray guns you can use. It will also provide a higher volume of air than most turbine compressors which will provide for greater production abilities than a turbine HVLP Spray gun. There will be a variety of air cap options to alter the fan pattern and CFM applied to the coating which will allow for a greater diversity of application scenarios and techniques. The purchase of the compressor will allow for use of a variety of air tools. The main disadvantage is the additional initial cost for the compressor.
When an HVLP Spray Gun is Right for You and When to Choose A Turbine HVLP or Compressor Driver HVLP
HVLP is right when
- Coatings are not heavy bodied coatings (heavy bodied coatings including zinc, epoxies, high solid industrial coatings,)
- You want to save on coating cost
- Emissions need to be reduced or controlled
- You want to control overspray
HVLP turbine is right when
- You need Portability of your spray gun
HVLP AIr Spray Guns are ideal when:
- You want to have options for other types of spray guns
- You already have a compressor that is large enough for a HVLP Spray Gun
- You want to be able to have multiple painters
- You want to have a variety of options in regards to your spray pattern and production