How to Thin Latex Paint

Different paints have varying level of thickness or viscosity. With this, you cannot easily interchange the use of different kinds of color. 

For instance, latex paint, being a water-based paint, is generally thicker as compared to oil-based one. It must be diluted or thinned with water to achieve a better consistency.

Thinning your paint is most important if you intend to distribute a thin mist of paint, or if you are using a paint spray gun or nozzle. 

Materials which are too thick may find it hard to pass through the vent for the spray guns. It may also cause clogging, which will delay you from finishing your work right away.  

However, paint thinning is not merely mixing your material with water or thinner. Doing this requires care so you will not over-thin the paint.

Learning the Ropes

Read the following steps to learn how to thin the latex material.

Check the thickness of your paint.

Before anything else, check if your material is too thick for use. Open your can of paint. Once opened, stir the stuff slowly. Do this for five to ten times.

It is also advisable not only to mix in a circular motion but also to do it in an upward and downward spiral movement.

This way you will be able to reach the materials which settled at the bottom of the container. 

Instead of merely stirring, you may also pour the material repeatedly from one bucket or paint can to another. 

There are also electric drills with paint mixing attachments as an alternative for simple sticks. These tools stir fluid more thoroughly. 

popcorn ceiling getting spray painted

Now, check the thickness of your material. This can be done by observing the paint coming off the paint stick.

Slowly lift up the stick out and observe how the material flows down. If it is coming off perfectly and looks like a smooth and thick cream, it may not need to be thinned.

Overthinning will ruin the consistency of the material and may make the material unusable instead. Not only that, over thinned material may not be able to cover the target surface completely.

On the other hand, if the material remains on the stick or comes off slowly or in clumps, it needs to be thinned further to create a better consistency.

Another way to check the thickness if by making use of a funnel instead of a stick. Just hold a conduit over the can and then pour the material into the tube by using a ladle.

The test is this - if it flows freely through the funnel, then the paint is fine, and the consistency is thin enough. Otherwise, it will still need to be thinned.

Prepare the paint.

To begin with, pour the material into a bucket. The amount of material to be used depends on the size and scale of the project you are working on. Ultimately, it boils down to your judgment.

However, as a rule of thumb, you may want to use at least a 5-gallon (19 liters) bucket for massive projects. Thinning a large patch of latex will ensure consistent results.

On the other hand, for quantities under 1 gallon (such as 1 pint), you may use a smaller bucket.

Add the right amount of water.

Again, the mixture of material and diluter (whether it may be water or thinner), depends on your ideal consistency. If you are not sure of the measurements, start by pouring a small amount of water first, stir, and check. 

water color paint mixing

Most users follow simple ratio such as for every gallon (approximately 3.7 liters) of paint you plan to use, they set aside 1/2 cup (118 ml) of water.

It is essential that the water is stored at room temperature.

As mentioned earlier, start with small amount of water first.Do not pour it all at once. Too much water will ruin the consistency.

Ultimately it may no longer be usable. Instead, pour it into the bucket in small increments while ongoing the stirring process. 

When thinning latex paint with water, remember that the amount of water you must add would vary among brands.

Typically, latex with higher quality is thicker. Hence you should add more water.

On the other hand, low-quality latex is thinner, and so you do not have to add more water as compared to the high-quality latex.

Remember to never add more than four cups of water per 1 gallon of latex paint.

Otherwise, this will render your mixture unusable for it may already be too thin. Now if you are using pints of material, the usual mix is adding two tablespoons of water per one pint of latex.

Stir the paint.

After you have come up with the ideal mixture, continue stirring the material and adding water gradually. You may make use of a stick to stir the mixture thoroughly.

Move the stick upward, and downward spirals. 

You may also check the viscosity or the thickness of the material by pulling the stick out and observing how fast the material runs off the stick.

If you find that it is too sticky, add a little bit more water. Continue stirring, watching the thickness, and adding more water until you reach your desired result. 

workshop with different set of paints

Add in small increments only. Remember to mix properly as the too thick material may cause clogs to your sprayer. In fact, it will not spray out well if it is too viscous.

Another of creating the perfect consistency is by pouring the material from one bucket or can to another, over and over, until you reach the proper consistency.

Pour the mixture through a funnel.

Usually, if you buy paint, it comes with a small funnel. Scoop it and observe how quickly or slowly it flows through the tube.

Depending on the size of the funnel and the amount of paint it can hold, the time the material flows thoroughly is not always the same.

The key here is to observe how freely the material flows. If it does flow through the funnel smoothly, then it is good to go. Chances are it will not be hard to use it as it will not clog the sprayer or the nozzle. 

Test the mixture.

Before starting painting, test the mixture you created before spraying into a larger surface area. To do this, just pour in a small amount of diluted solution in the sprayer or paint brush.

Spray on the target surface and observe how the paint behaves. 

If the mixture is too thin, you will notice that it will drip easily if you are painting a vertical surface. On the other hand, if it is too thick, you will see that it will achieve a texture like that of an orange peel. The perfect consistency will quickly dry and not drip. 

Start your project.

 Now if you are ready with your mixture, pour in enough amount of paint into the strainer, with a bucket on the bottom catching the strained paint.

worker using a paint sprayer

This will remove any lumps or impurities which will clog your machine. Doing this before painting saves you from all the hassle and will not interrupt your work while it is ongoing. 

Pour the strained, beautiful mixture into the sprayer. Start spraying with low pressure so as not to release too much paint in the beginning. 

This way you can predict or control the amount of paint being released by the sprayer. 

If you are spraying a horizontal surface, start spraying from left to right per layer. Do not start from the middle and moving either way.

This will result in an uneven surface. If you are working on a vertical surface, start from the top and slowly spray down. 

After finishing spraying the first coat, allow it to dry first thoroughly before spraying the second layer. You can check this by softly touching a tip of the surface.

Other Tips for Using Latex

When using high-gloss latex paint, it is necessary to use a primer. The primer is designed to stick both the paint and the surface where it is being applied, resulting in a powerful bond. 

Do not store latex paint for too long. Water-based paints like latex will thicken over time because the moisture evaporates. After which, its consistency will become much harder in texture.

Also, check out the below video for more tips:

Wrap Up

To sum up, thinning paint for spray gun can be a bit tricky. However, before attempting to do so, understand the different characteristics of different kinds of paint.

Higher quality latex paint usually is thicker than those with lower quality. From here, you know which one requires more water to be thinned.

Remember not to be too aggressive in adding water or thinner to your material. If you add more than what is required, your paint will be too small that it may no longer be able to cover the target surface.

There is no specific measurement as to the mixture of paint and water, or color and thinner. Test the mix from time to time to reach the perfect consistency.

In every painting project, preparation plays an important role. This applies even on how to thin latex paint.