Spraying Acrylic Paint with HVLP – Some Things to Consider

Expert painters believe that acrylic spray painting is a mindset. HVLP spraying is slow, though it’s not as slow as using a brush and roller. Before starting to spray acrylic paint, you need to go in with an open mindset.

Know exactly what you need before you start painting. For example, you’ll need extras like films, tapes, lubricants, extension poles, and plastic sheeting. Here are some considerations to look at when spraying acrylic paint with an HVLP spray gun.

HVLP Sprayers

HVLP sprayers need the power to spray paint. A unit with more power will tend to be more expensive. For example, the lowest power rating is a 2-stage while the highest is a 5-stage. The 2-stage is therefore more affordable than the 5-stage.

HVLP sprayers work like reverse vacuums as they convert air into power. More stages can be used to create more power. Additional onboard compressors can be used to increase power further.

Best HVLP Sprayer for Spraying Acrylic Paint

You will need a minimum 4-stage turbine to spray acrylic paint. In fact, a 5-stage turbine would be ideal. Even with 5-stage units, paint thinning is required. If you buy cheap 2 or 3-stage sprayers, you’ll struggle to spray anything with a viscosity higher than water. The sprayer just won’t generate enough power. The acrylic paint will have to be so thin that it will be unusable.

Setting up an HVLP spray gun

Patience is required when setting up an HVLP spray gun. If you get the setup wrong, you may have to redo the whole job by sanding down and respraying. A cup under the gun is the reservoir that has the paint. Compressed air is directed to the gun and a pressurized pot separately.

Applying force to the trigger forces paint in the cup into the gun where it meets the compressed air headed to the gun. By properly regulating the gun, you can atomize the paint particles thus enabling it to spray better.

In case you have a viscous material, you just need to increase the air to the gun. However, you may suffer from overspray which is a big problem, especially for occupied residents. This is where paint particles bounce back from the surface. Overspray can be avoided by setting the gun right and thinning the paint correctly.

You can use water and Floetrol to thin the paint. If you can swirl the mixture with a stick and you can see the swirls, then you have the right mixture. The mixture is also okay if when you lift the stir stick, the paint dissipates into itself in seconds.

In case you can’t avoid overspray, then you can use drop cloths to avoid paint spreading on carpets or furniture. Everything needs to be covered in sheets or plastic.

Spraying acrylic paint is a trial-and-error process. This is because the air and material must be regulated by the user. Specific settings may work for you today but won’t work for you tomorrow due to environmental changes like humidity and temperature for example. So always try to get the thinning right and then move on to get the correct settings before you start the painting job.

How To Thin Acrylic Paint for HVLP Sprayer?

Always ensure you have all the necessary personal protective equipment before you start thinning acrylic paint. You should have gloves, caps, glasses, and a pair of safety shoes. Water or paint thinner liquid can be used to thin acrylic paint. Water is mostly used since it is readily available. Here is the step-by-step process to thin acrylic paint for your HVLP sprayer.

  • Step 1

A 90:10 (paint: water) ratio is recommended for thinning acrylic paint. You can therefore mix a gallon of paint and 12 to 13 ounces of water. Then mix the paint well using a stir stick. Finally, check whether you have achieved the right consistency with a strainer. The strainer will also trap any lumps.

Alcohol and paint thinner can also be used to thin acrylic paint. Alcohol is best when fast drying is important. This is because alcohol evaporates rapidly under room temperature, unlike water. Paint thinner also enhances the stretchability of acrylic paint, and you can use it for thinning. You can use a ratio of 4:1 when mixing acrylic paint with paint thinner.

  • Step 2

You can also use a funnel to check if you’ve achieved the correct consistency. After placing a bucket down, pour the mixture into the funnel and allow it to flow freely to the bottom. The funnel will help you check whether there are any clogs.

  • Step 3

If you feel that the thickness of the mixture is not right, then go ahead and increase the ratio of water. It is recommended to add water in 5% increments until you achieve the thickness you need. In case you find that you’ve thinned the paint too much and it runs out, don’t worry, you can correct this. Just add half a cup of paint to the mixture and stir till you get the desired consistency.

  • Step 4

Once you achieve the right thickness, fill the spray gun up to ¾ with the mixture of paint. Test the spray gun on a test surface by pressing the trigger a few inches from the surface. Check if you have a clear spread. The mixture should not be slowed down or stuck on the nozzle. If you get the desired result, then you can continue to spray paint the item you wanted to.

In case you don’t get the desired result, then add water again and stir and repeat the process. By mixing and thinning properly, you ensure that the color will last longer. Painting with acrylic paint will save you a ton of money while giving your surface a charming finish.

  • Step 5

Once you’re done with the setup, now it’s time to do the actual spraying. You could paint the wall, wood, or any other surface. Hold the gun perpendicularly at a distance of 5-8” from the surface you’re painting. If it’s tilted, you’ll get uneven coverage.

Tips for spraying Acrylic Paint with HVLP

As you attempt to spray acrylic paint with HVLP, here are a few tips.

  1. Do not attempt to learn on the job. You could get an old piece of furniture to do your settings and get the hang of spraying acrylic paint.
  2. Avoid spraying light and fast coats as this will give a rough and patchy finish due to the paint drying fast. In some instances, the paint may even dry before touching the surface.
  3. The best spraying strategy is to move the gun slowly across the surface you want to paint. Spraying acrylic paint with HVLP is all about practice and just know that you won’t get it right the first time.
  4. Acrylic paint must be thinned well by mixing 10% water in it. The amount of water you can add is quite subjective. You can add more or less until you achieve good consistency. If you don’t achieve the right consistency you could end up blocking your HVLP gun or having messy blobs on your workpiece.

HVLP Spray Gun Common Problems

HVLP spray guns are better than conventional spray guns since they have way less paint wastage. However, it may take a bit of time to get used to HVLP spray guns. You won’t always get the desired paint finish by just increasing the air pressure. Here are a few common problems you are likely to encounter when using an HVLP spray gun.

  1. The paint appears uneven and you’re not getting the required finish – This could be due to the paint not being thin enough to be used by the HVLP spray gun. Always check your technical data sheet for any paints you’re using to see if they can be used with HVLP spray guns. If you’re experiencing orange peel when painting, then try a smaller fluid nozzle.
  2. The gravity gun is not getting any paint – If your HVLP spray gun isn’t getting any paint, you could thin your paint more, use a larger fluid nozzle, or use a filter with a larger aperture screen.
  3. The spray gun is spitting and dripping – A spray gun will spit if the fluid nozzle is not tight. It could also be due to the fluid nozzle and fluid needle wearing out and needing replacement.
  4. Inconsistent spray pattern – This could be due to an insufficient air supply or a worn-out air cap.

Spraying acrylic paint with HVLP spray guns is a massive undertaking that needs tons of patience. If you want to start painting, then a 4-stage or 5-stage spray gun is ideal. Strive to get a correctly thinned paint mixture as this will ensure high-quality finish.

You can use water or alcohol to thin the paint until you get the ideal consistency. With proper technique, you can get a great finish with HVLP spray guns.