How To Thin Enamel Paint For Spray Gun?

Wondering how to thin enamel paint for a spray gun? Enamel paints are prized for their unique thickness and texture and can be used to paint a lot of different materials.

It is used to paint windows, doors, woodwork, trims, and different types of floors. Everyone is a fan of this paint because of its smooth, glossy, and professional finish.

Enamel paints can be both oil-based and water-based. Enamels are available in a variety of colors and textures like high gloss, gloss, semi-gloss, eggshell, satin, etc. Thinning Enamel paint is necessary to make it compatible to use with a paint spray gun.

Most people are not aware of the thinning process for enamel, so, we have brought a comprehensive guide to teach you how. In addition, you would also know why it is done and how to do it correctly.

Why Thinning Enamel Paint Is Necessary?

Pouring thick, hard Enamel paint into the spray gun would be a straightaway disaster as it will either lead to blob formation or leave the spray gun with no efficiency or functionality.

This paint is on the thicker side of the paint spectrum, therefore, enamel needs to go through the thinning process to make sure it can be delivered efficiently through the spray gun.


Spraying thick enamel paint is not the smartest idea, therefore, you should carry out the thinning process first.
To reduce the thickness and viscosity of enamel, it is usually mixed with a paint thinner.

Most people believe that to thin oil-based Enamels, mix it with water, which is entirely wrong. Thinned paints are easy to apply and reduce the drying time and orange peel.

Gear Needed For Thinning Enamel Paints

Following things, gear, or equipment is needed before thinning enamel paints.

  • #1: Safety Equipment – Arrange goggles, gloves, and respirators for thinning enamel. Wear a respirator or mask when thinning oil-based paints as it emits poisonous fumes.
  • #2: Stirrer & Strainer – You will be needing a high-grade strainer and a stirrer. Utilize plastic or wooden stick as a cheaper alternative for stirrer. The strainer is used to separate dust, dried flakes, clumps, and other impurities.
  • #3: Paint Tool – Have a spray gun, roller, or brush ready to apply thinned enamel
  • #4: Thinner – Besides all essentials, have the paint material and the right thinner.

Type Of Enamel Paint Thinners

The paint market hosts a variety of thinners which makes people confused as to what type of paint thinner to be used. The following list will clear the confusion regarding thinners and their use.

#1. Acetone

Though it is not recommended Acetone can be used as an enamel paint thinner. Therefore, it is best to clean brushes or remove paint from different surfaces.

Acetone has the ability to dissolve plastic, so, things can get complicated when painting on a plastic surface.


#2. Turpentine 

Turpentine can thin enamel paint but it is best not to do it with this thinner. It boosts the drying time of many oil-based paints. Besides clogging the airbrush, it can damage the surface as well.


#3. Water

It can be used to thin water-based enamels.

#4. White or Mineral Spirit

This is the best option for thinning enamel paints on the list. It does not affect the drying time or brightness. It is relatively cheaper than some other options listed here.

#5. Alcohol 

Alcohol can be used as a thinner as well but it mostly depends on the brand of enamels.

#6. Lacquer Thinner

It has the ability to thin enamel but has various drawbacks. It leaves a dull or poor finish.

Of all the options, it is better to stick with Mineral spirit. There are several ways and different thinners but Mineral spirit mostly brings desired results.

Before thinning, perform a small test to figure out if the paint is oil-based or water-based. Try adding a few drops of water to the paint, if it gets mixed well, it is water-based paint and vice versa.

How To Thin Enamel Paint For Spray Gun?

Google is flooded with questions like how to thin enamel paint to use on a paint sprayer, often asked by people who have taken DIY paint jobs. Along with some answers, many misconceptions and speculations are circulating the web as well.

Therefore, to clear things once and for all, we have shared a comprehensive, step-by-step thinning procedure of enamel paint to help you out.

  • Step #1: Follow The Safety Protocols – Before moving forward with the thinning process, it is important to wear safety equipment and follow all the safety guidelines. Wear safety goggles, a protective respirator or mask, and a pair of gloves. Choose a ventilated space to perform the enamel paint thinning process. A well-vented room is necessary as exposure to poisonous fumes may lead to breathing problems, dizziness, and nausea.
  • Step #2: Inspect The Paint Label – Checking the paint can label gives you information about various things like whether it is oil-based or water-based, the amount of thinner recommended, brand, paint expiration date, and more. Along with the suggested ratio, some paint labels go as far as to recommend the thinner as well.
  • Step #3: Test The Paint – Not many of you know but not all enamels need to be thinned. Firstly, remove all the lumps using a strainer otherwise, the spray gun will be clogged. Pour a small amount in the spray gun, and test it on a testing board, if the paint does a good, smooth job, no need to add a thinner.
  • Step #4: Use Paint Strainer – If the paint needs to be thinned, pour it into an empty bucket using strainers to remove lumps.
  • Step #5: Initiate The Thinning Process – In order to thin enamel paint, use the proper enamel paint thinner ratio of 1/3 based on the paint type. The correct enamel paint thinner ratio is 1:3 (1 part paint thinner and 3 parts enamel paint).
  • Add the recommended amount of thinner to the enamel paint bucket. To be on the safe side and avoid thinning too much, start with a 1/3 thinner-to-paint ratio.
  • Step #6: Second Testing – Test the paint on a testing surface or cardboard to check the right consistency of the mixture. If it sprays evenly and smoothly, refill the spray gun and start to paint. If desired results are not achieved, there is more to follow.
  • Step #7: Add More Thinner If Required – Continue to add a small amount of thinner to achieve the desired thinner to paint ratio. Test again, if still, the paint is not smooth, continue to add more to achieve a 2/3 thinner to paint ratio. It is advised not to go beyond the said ratio.
  • Step #8: Getting The Perfect Ratio – Once you have achieved the perfect ratio, fill up the spray gun and paint beautiful patterns.

Mistakes To Avoid When Thinning Enamel Paint

A painter needs to be aware of the don’ts of thinning enamel paints as they are equally important. Here’s what you should avoid when undertaking the thinning process.

  • This is a common problem and you will have to encounter it as well if you would not care. Using too much of a thinner increases the risk of thin paint material or runny enamel. It becomes practically useless and can not stick to the surface.
  • Another one is using the wrong thinner, some enamel paints do not need thinners at all whereas some do. For thinning Enamel, usually Mineral Spirit or Turpentine.

Useful Tips For Thinning Enamel Paints

  • Step #1: Test the consistency and thickness with a spray gun, paintbrush, or paint roller to prevent over-thinning.
  • Step #2: Only use one thinner. For instance, do not add water after using Mineral Spirit first.
  • Step #3: Use a funnel test for exact measurements.
  • Step #4: Always use a stirrer, do not use your hand to stir paint.
  • Step #5: Follow the thinning instructions given on the thinner label for best results.
  • Step #6: Weather influences the thinning process of enamel paints, during humid temperatures, a more thinning ratio is required.


It is not that difficult to thin enamel paints, just a few steps, and a proper ratio, and you’re good to go. Using the right thinner proportion will not only help with good consistency but also with retaining the glossy nature of the enamel paints.


Hi, Cristopher here. I have been working in the home improvement industry for the past 15 years, and I have developed strong expertise in spray guns and paint sprayers. I have a deep understanding of how these tools work and how to get the best results from them. In addition to my practical knowledge, I am also running this website dedicated to sharing tips and tricks for using spray guns and paint sprayers.

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