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WHAT IS HVLP?
Conventional spray guns use a compressor to atomize the coating (Paint). General rule of thumb is that this type of gun puts 1/3 of the coating on the substrate being coated and 2/3 into the air.
HVLP Spray Guns HVLP is a classification of guns created by the government to reduce the emissions created by traditional conventional spray equipment. The basic rule of thumb is this method puts 2/3 of the coating on the substrate and 1/3 in the air.
HVLP Guns use an efficient cap design (the cap is the piece at the front of the gun with "horns"). This cap design creates a high volume of air flow at lower air pressures (therefore the name HVLP - High Volume, Low Pressure) to create a fine, soft spray pattern (about 10psi) with high atomization. By using such a high velocity air flow through the air cap, HVLP is able to achieve both high transfer efficiency and low overspray (wasted paint in the air). 2/3 of the coating on the substrate and 1/3 in the air.
Many people ask what their cap pressure is? This is not very relevant. By using the suggested inlet pressure by the manufacture, your gun, if marked HVLP, is supposed to translate its suggested inlet pressure into around 10 psi at the air cap. i.e. a 29 inlet pressure on some guns equate to 10psi at the cap while 44 inlet pressure on some guns equate to 10psi at the cap. It all depends how the manufacture decides to design their gun. So depending on the brand of spray gun, you will see a wide disparity of inlet pressures, but they should all
equal 10 PSI @ cap.
Besides, most people "cheat" and go as high as they can without splitting the fan pattern to get the most material delivery and best atomization - so your cap pressure generally is higher than 10psi anyway so don't worry about it - just don't do it when the EPA is looking... For those very particular people, we have and most manufactures offer air cap test kits, but they usually run around $50-$100.00. therefore does not recommend them due to cost considerations.
Please note: There are way too many HVLP guns on the market. They are all not the same!
At we have spent a lot of time researching the best most professional spray guns on the market. Due to popularity, the amount of HVLP spray guns out there is confusing at best! There are many cheap aftermarket HVLP guns not worth a penny and Turbine HVLP guns which we do not recommend. Some HVLP guns from China cost $10 and are sold by our competitors for $60.00 (you will never find such a gun here). All are called HVLP as a class like the word (car). But, as you know, there are bad cars and good cars on the road... Have no fear! at we only try to bring you the best of each class of "cars" (HVLP guns).
So HVLP Saves me 30%-35% of my material costs! Great, but can I spray the same way?
No, HVLP is a different way to spray. If you are used to spraying with conventional equipment and are a "fast and loose" sprayer, please look at the newer trans-tech or (Reduced Pressure) spray guns. For new sprayers or those willing to adapt and learn what is being taught in most finishing schools today HVLP is ready for you.
HVLP sprays different because of design. A conventional gun uses a lot of air to break up the paint. 50 PSI inlet on a conventional gun gives you 50 PSI out at the cap. That's a lot of power, but also a ton of overspray and wasted paint. Depending on the brand you choose, an HVLP spray gun may require 18-50 PSI in to produce the mandated 10 PSI at the cap. Since the paint exiting the gun at 10 PSI will not carry as far as at 50 PSI, the gun must be closer to the painting surface. The recommended 8"- 10" distance for most conventional guns guns should be 4"-6" for HVLP depending on the painter's technique. Being closer to the surface also means you seem to move with a faster stroke to avoid runs. However, since more of your paint is hitting the surface your actual production time will be about the same.
Please note: Since your material hits so close to the surface, medium and slow reducers and hardeners should be used to allow for good solvent escape and flow out. This helps prevent micro bubbles in your finish. This is very important for woodworkers who may not have temperature control in their spraying areas.
Is it worth leaning such a new technique?
30-50% material savings is easy to obtain and at that rate your equipment pay-back period is short. As your HVLP technique improves, so will your savings.
Why are you guys different than my paint store and have so many tip sizes with your guns?
We are fanatical and particular at SprayGunWorld and SprayGunIndustry. We don't believe that 1 size shoe fits all people. This is even more important today with the newer technology. In the old days with conventional guns, if the material was too thick you could simply crank up your air pressure on the gun and "force the material out" - no problem. However, today's guns are designed to operate in a certain range. Therefore, no only will your gun no longer be in compliance, but your fan will start to distort. To solve this problem, you should always have the correct tip sizes as recommended by the manufacture for the certain viscosities of paint you are using. At we have viscosity charts and many tip sizes in kits to help you get the best results.
We carry all the major players in the professional end of spray equipment.