How To Thin Paint For Sprayer? – Detailed Guide

If you don’t want to mess up with paint and the sprayer stuff, use the paint in the right consistency. Depending upon the project and sprayer requirements you need to maintain the consistency of the paint at a specific level. If you don’t know how to thin the paint for the sprayer you can’t expect an even and smooth finish.

Depending upon the type of sprayer and paint you are using you need to adopt a specific thinning agent and technique. Also, you need to learn about different types of thinners and how they work with specific types of paints. This guide covers different ways to thin the paint for a sprayer.

How To Thin Paint For Sprayer?

Thinning of the paint usually involves four to five steps including choosing the right thinner, straining the paint to remove the lumps, adding the thinner, and performing consistency tests.

1. Choose The Right Thinner

Depending upon the type of paint that you are working with you need to choose the right thinner. Latex paints, acrylic paints, or general-purpose water-based paints can be thinned with water. No specific solvent or agent is needed for these paints. For oil-based paints, you need organic solvents to adjust the viscosity. A wide range of organic solvents like acetone, lacquer thinners, alcohol, turpentine, and white spirit are available.

Depending upon the application and type of oil-based paint you want to thin you need to choose a fully compatible thinning agent. Product labels and descriptions can help you choose the best thinning agent. The efficiency of the thinning process largely depends upon the quality of the thinner. The better the quality, the smoother the finish you will get.

2. Use The Right Amount Of Thinner

Using the right amount of thinner is the most crucial part of the process. You need to adjust the paint thickness according to the type of sprayer and application. Over-thinning results in a lighter shade and poor coverage. For general purpose thinning it is recommended to keep the paint-thinner ratio 4:1 or 3:1. If you are using an HVLP sprayer for a thick oil-based paint, you can keep the paint-solvent ratio 2:1. Under-thinning can cause clogging in the spray gun nozzle.

Pro Tip: Paint at low temperature appears thick which can be deceiving. To avoid the over-thinning make sure the paint is at room temperature and you are adding thinner.

Generally, there are three types of spray guns that are used: High Volume Low-Pressure sprayers, Low Volume Low-Pressure sprayers, and airless spray guns. For LVLP and HVLP sprayers, you need to thin the paint quite a bit. Generally, a 10% thinning ratio is recommended for HVLP and LVLP sprayers.

Airless sprayers may or may not require thinning. Paints formulated for airless sprayers come in thin consistencies and can be directly used with the airless sprayer. If you want to use regular paint with an airless sprayer, the recommended paint to thinner ratio is 4:1.

3. Prepare A Flawless Stuff

Oil-based paint is not free of lumps. Therefore it is crucial to pour it through the strainer to remove all the lumps from the paint. Water-based paints lack a homogeneous consistency i.e they can be thick at the base and thin on top. Before adding the thinner you need to mix the paint well to get a homogeneous consistency throughout the container.

4. Perform A Consistency Test

Once you have mixed thinner and paint in a specific proportion, it’s time to perform a consistency test. You can perform a consistency test either with a funnel or a sprayer. The funnel test involves a lot of guesswork. Pour the paint through the funnel and if it flows smoothly at a consistent speed it is ready to be used. If it moves too slowly you need to add more thinner.

If you are not experienced enough to guess the desired consistency with a funnel test you can perform a sprayer test. Apply a paint stroke with a sprayer on the cardboard or any test surface. If the paint goes smoothly through the nozzle, you’re all done with it. Also, check if it gives the desired coverage and shade or not. If the excessive paint is dripping or stains are bleeding through the paint layer, it means you have over-thinned the paint.

Thinning Of The Oil-Based Paints

Oil-based paints like semi-gloss enamel are thinner in consistency than their latex counterparts. However, for proper atomization, you need to thin the paint. Some HVLP sprayers can handle these paints with thick consistency however it happens in rare cases.

Turpentine or mineral spirits are used to adjust the consistency of the oil-based paint. Generally, 2:1 paint to thinner is recommended for the HVLP sprayer. However, it depends upon the concentration of thinner and the original viscosity of the paint.

Supplies needed to thin the oil-based paints

• Paint Stainer
• Buckets
• Funnel
• Thinner
• Clean Stirrer

Steps to thin the Oil based paints

1. Straining

When you are working with oil-based paints this is a crucial step. Before mixing it with a thinner you need to strain it to get lump-free painting stuff. Take a clean bucket or container and pour the paint through the strainer into it. Your paint is ready to be mixed with the thinner.

2. Pouring the Thinner

Take two equal sizes measuring cups and start pruning paint and thinner into a new container. For every three parts of paint add one part of thinner.

3. Stirring

Use a clean paint stirring stick and keep on mixing to get a homogeneous consistency of the paint and thinner.

Check The Consistency

Pour the paint through a funnel. Paint should run freely through the funnel at a medium pace. If it flows too slow or too fast you need to work on it. If it’s too slow (it usually happens when you keep the ratio 4:1) you need to add more thinner. Most of the paints do not follow a strict ratio. Start pouring the thinner slowly and keep on mixing with the stirrer stick until you get the desired consistency.

How To Thin The Latex Paint?

Latex is a water-based paint that is commonly used for the ceiling and walls. The paint is less messy than the oil-based paint and offers more coverage with a little amount. Also, it is more economical but less durable than oil-based paints.

Latex paints are considerably thick and you need to dilute them before using them with a handheld sprayer. However, some latex paints do not support thinning and there you can’t use them with a sprayer.

Steps to thin Latex Paint

Follow these steps to thin the latex paint:

• Latex paints do not form lumps so there is no need to strain them. However, these paints cannot maintain a homogeneous consistency through the container. So the first step is mixing. Thoroughly mix the paint with the stirrer to get a flawless consistency.
• Pour the required volume of paint into a clean bucket. Do not pour more than what you need since the paint becomes thick again if kept for too long.
• Start adding water with a measuring cup. It is advised to begin with a quarter cup. Keep on mixing. It is advised to stir well to avoid irregular concentration.
• Once you think paint is thin enough to be used with a sprayer take a consistency test. You can either use a funnel test or a sprayer test.
• Cleaning is not as messy as oil-based paints, so it is advised to do a sprayer test. It helps you get an idea if the paint is flowing freely through the nozzle or not. Also, you will be able to see the coverage and adhesion on the surface that you want to paint.
• If the paint is too thick for the sprayer the atomization will be slow and you will not get smooth coverage.
• Clean the sprayer and again add thinner. Keep adding until you get the desired consistency.

How To Thin An Enamel Paint

Enamel paints are oil-based paints that are widely used for commercial-grade furniture and wood painting. Enamel paints are also used on various materials like polymer and metal. These paints offer semi-gloss and super gloss finish for wooden furniture. Also, it is more durable than regular oil-based and acrylic paints.

List Of Thinners and How They Work With Enamel Paint

White Spirit: It is the best thinner choice when you are working with an oil-based enamel. White spirit does not affect the shade and adhesion properties of the enamel paint.

Turpentine: Turpentine works best with oil-based paints, but it is not recommended for semi-gloss enamel paints as it affects the glossy finish of the paint.

Acetone: Acetone is one of the best thinners that you can use to thin the Enamel paint. It is highly recommended for wood painting applications, however, you should avoid acetone for polymer and plastic painting applications.

Alcohol: Alcohol is generally used for the thinning of oil-based paints. However, you can’t expect the same results every time. If you want to paint antique furniture, alcohol is not recommended.

Lacquer Thinners: Lacquer thinners are not recommended for enamel as they promote discoloration. It results in a dull finish and you may not get the desired shade. Also, lacquer thinner can melt the plastic and polymers. So it is not recommended to use lacquers for enamel thinning.

Mineral Spirit: The mineral spirit is a universal solvent that you can use for all enamel paints. Mineral spirits do not affect the adhesion properties of the paint.

Things That You Need to thin Enamel Paint

• Respirator
• Pair of gloves
• Safety Goggles
• Mineral/White spirit
• Clean Bucket
• Funnel
• Stirrer sticks
• Paint Stainer

Steps to thin Enamel Paint

Follow these steps to thin the enamel paint for the sprayer:

• You need to put all the safety equipment to avoid the fumes from oil-based paints and organic solvents. A respirator will help you breathe properly while working with a large volume of organic solvents.
• Open the paint carefully and mix it thoroughly with the help of a stirrer to get a flawless consistency.
• Put a strainer on the top of the bucket and pour the paint through the container. The step is crucial to remove the lumps from the enamel paint.
• Now pour a specific amount of paint that you want to thin into another bucket. You can start with 3:1 or even 4:1. Start pouring organic/white spirit slowly and keep on stirring with the help of a stirrer stick.
• After adding a specific amount of thinner, perform a spray test to avoid over-thinning.

How To Use A Viscosity Cup For Consistency Test?

If you don’t want to go with a sprayer consistency test you can use a viscosity cup or viscosity funnel. Once you have mixed the paint and thinner in the right proportion, pour it into the viscosity cup. If the paint flows smoothly through the cup the desired consistency is achieved. To perform this test you need to be experienced enough to guess the right viscosity. You may need to perform this test three to four times until you get the desired results.

Pro Tip by Pete Fagerlin

While performing these tests keep the record of the paint and thinner ratio. Note down the ratio that gives the perfect result. In the future, you can use this value to avoid guesswork and multiple consistency tests.

Can I Use A Paint Conditioner Instead Of a Thinner?

The paint conditioner cannot replace the thinner in the case of oil-based paint. However, you can use a paint conditioner for latex or acrylic paints. Water-based paints have relatively thin consistencies and a thinner can make them too thin for application. A conditioner comes in handy for extreme conditions.

If it’s too hot or too humid, you can add a conditioner to smoothen the flow of paint through the sprayer without altering its color, adhesion properties, and the original viscosity. Floetrol is one of the best paint conditioners that you can use if you are using an airless spray gun.

Frequently Asked Questions

What can I Use to thin paint for spraying?

You can use multiple solvents or thinning agents to thin the paint for a sprayer. If you are working with latex or water-based paint you can use water to thin the paint. In the case of oil-based and enamel paint, you should consider various organic solvents like turpentine, alcohol, organic spirit, and acetone.

Do I need to thin paint for the sprayer?

If you are using an HVLP or LVLP sprayer you need thin paint. The ideal paint-solvent ratio for thinning is 2:1 or 3:1 for these air spray guns. In the case of an airless sprayer, you need to thin the paint only if it comes in thick consistency. Recommended paint-thinner ratio for airless prayers is 4:1.

Can you run paint thinner through a paint sprayer?

Yes, you can run the thinner through a paint sprayer to remove the clogging or debris. Lacquer thinners are ideal cleaning agents for paint sprayers. A lacquer thinner can dissolve the clogged paint and help you get a debris-free atomizer and nozzle.

Does thinning paint change the color?

Thinning of the paint definitely changes the color. The color of the thinned paint will be lighter than the original paint color. You need to use a fully compatible high-quality thinner in the right proportion to reduce its impact on the color and adhesion properties of the paint.

How do you dilute water-based paint for a spray gun?

Pour the paint into a clean bucket and mix it well to get a smooth consistency. Paint-thinner ratio for water-based paints is 4:1. Add a small amount of water and mix it well. Keep on adding the water until you get the desired consistency.

Can I add water to the thick paint?

Water is a thinning agent that cannot be used to thicken the paint. If you have over-thinned the paint do not add anything to the mixture. Instead, you should pour the mixture back into the can containing thick paint. Mix it well with the paint to get a thicker consistency.

Wrapping Up Thinning Spray Paint Guide

I’m hopeful that this guide is gonna be a big help for your next painting project. It is advised to use organic solvents in a ventilated space. Also, you should store the organic thinners in ventilated rooms to avoid harmful fumes.

In addition to these guidelines, you must follow the instructions provided by the paint manufacturer. Every product comes with specific recommendations for the thinning agents and the paint-thinner ratios. The product-specific ratio will help you get a trouble-free experience.