How to Thin Alkyd Paint? And Some Tips on Applying It

When you are painting with alkyd, it is important to know about its unique properties, which is why we’ve written this article! Alkyd paint can be difficult to work with on account of its unique properties. However, once you understand how these paints work and what their limitations are, you can learn how to thin alkyd paint properly so that it applies smoothly and gives you exactly the result you want every time.

Read on to learn everything that you need to know about thinning alkyd paint!

Why Thin Alkyd Paint?

Alkyd paints are designed to dry slowly, allowing the paint to have a longer life span. Therefore, they do not dry as quickly as other types of paint. This slow drying time is what allows alkyd paints to go on thick and create an opaque finish. However, this is not always the desired result.

This type of paint can be quite thick, which makes them difficult to apply and leads to the risk of ending up with an uneven finish. If you want to paint in fewer layers or would like an even coat of paint, you need to thin the alkyd paint.

Alkyd paint is also thinned differently compared to other paints. If your project requires a lot of paint or you are using some very thick layers, you should use less thinner and if you are planning on having a thin layer of paint, you will use more thinner.

How Much Thinner Should You Use?

You will likely need to thin your alkyd paint slightly to achieve the desired finish. The amount of thinner that you use will depend on the desired finish, the paint brand, and the surface type that you are painting. It is important to use the right amount of thinner so that the paint is still workable, but dries quickly.

For example, if you need to paint 10 vertical feet of wall, you will likely need a lot of paint. You will need to use enough thinner so that the paint dries quickly so that you can finish the painting project promptly. However, you do not want to use too much thinner. Doing so will reduce the paint’s ability to cover and create a thick finish.

The more thinner you use when thinning your paint, the faster the drying time will be and vice versa. On the other hand, if you do not use enough thinner while painting with alkyd paint, there is a chance that your finish will appear lumpy or cracked.

When To Use Thinning Agent with Alkyd Paints

The best time to thin your alkyd paint is when you need to paint in fewer layers.

You may also want to thin your alkyd paint when you are painting on a porous surface, like fiberboard, that does not accept paint well.

When the paint is too thick to use it. You will need to add thinner to it so that you dilute it to the required viscosity.

How To Thin Alkyd Paint?

1) To begin the thinning process, gather all items that you will need. These are

  • Clean bucket
  • Funnel
  • Strainer
  • Stirring stick
  • Thinner

2) Take an empty bucket and align it with a strainer that will hold clumps of paint.

3) Open the paint can and carefully pour the paint into the bucket through the strainer, aiming for the center of the bucket, and once done, remove the strainer.

4) Pour the thinning agent into the bucket following the guidance of the paint manufacturer to guide you on the ratio of paint to thinner.

A key point to note is that you should use the ratio of 1 part thinner to 3 parts paint, to ensure that the paint is more than the thinner. This ratio is the standard ratio used so that we avoid making the paint very runny or too thick. This ratio varies depending on the type of applicator being used.

5) Use a clean wooden or plastic stirring stick to mix the thinner and the paint thoroughly to ensure that the two elements totally amalgamate.

One way to know that the mixture is ready, is by pouring it on a funnel, if it runs down well, then it is ready, but if it is slow and does not run down the funnel, you will have to add in more thinner to the paint to make it less viscous.

Now that the alkyd paint is thinner, you will have to paint more coats than when the paint has not been thinned. Also, because you are using alkyd paint.

You will also have to wait for 24 hours for the paint to dry up so that you can spray another coat.

How To Thin Alkyd Paint for Spray Guns

Thinning alkyd paint to be used in a spray gun is very important. The paint viscosity needs to be thin and runny to avoid clogging paint on the sprayer nozzle.

When thinning your paint for a sprayer, use a ratio of 3:1 or 4:1 of paint to thinner. This will ensure that the paint is less viscous and therefore runny enough to be used on a sprayer.

How to Thin Alkyd Paint for Brushes and Rollers

If you plan on thinning your alkyd paint for brushes and rollers, you will want to thin the paint with a thicker mixture. You do not want the paint to be too runny as this will cause the paint not to hold up on the brush or the roller. For this, use the ratio of 2:1 of paint to thinner.

Cleaning brushes after painting with alkyd paint can be a daunting task, therefore after you are done with painting, immediately pour some thinner into a bowl and dip your brush to clean off the paint. Ensure that the paint has not dried up because the paint may not come off if it dries up on the brush.

Tips for Thinning Alkyd Paints

  • You should note that it is vital that the paint be thinned at room temperature because, during cold days, the paint might appear thicker than it is.
  • It is essential to note that different paint brands have different viscosities out of the can. You will likely need to adjust your paint with paint thinner based on the specific paint brand that you’re using.
  • If a lot of thinner was used, it will turn the color of the paint to a lighter shade. In case this happens, instead of adding more thinner to your alkyd paint, you will want to add more paint. This can be done by blending the already thinned paint with fresh paint.

Effects of Thinning Alkyd Paints

When you thin alkyd paints, you are reducing the amount of pigment that is distributed in the paint. You will also reduce the volume of the paint. Therefore, the paint coverage may be less than when you originally applied the unthinned paint.

When you thin alkyd paints, you also reduce the amount of binder in the paint. This can cause the paint to crack or chip more easily. The more thickener that you add to your paint, the thicker it will be. Therefore, it will take longer for the paint to dry.


Alkyd paints are designed to dry slowly, allowing them to have a longer life span. Therefore, they do not dry as quickly as other paints. This slow drying time is what allows alkyd paints to go on thick and create a thick, opaque which is not always the desired result.

If you want to paint in fewer layers or would like an even coat of paint, you will need to thin the alkyd paint. When you are painting with alkyd, it is important to know about its unique properties so that you can use them to your advantage

Alkyd paint is oil-based and requires thinning before use. It needs to be thinned to avoid clogging the tip of a brush or the paint being too thick for it to flow properly through the nozzle. Alkyd paints are normally formulated with a high viscosity, which makes them much thicker than standard acrylics. However, if your alkyd paint has become too thick and is difficult to use, you can thin it out with a few different types of oil-based thinners.

It is important to choose the right diluent when working with alkyd paints because they require a thinner that is specific to alkyd paint and compatible with the surface being painted. A common way to thin alkyd paint is by using additives like thinner or mineral spirits. However, this will come at the expense of durability and environmental degradation.

Thinning alkyd paint is essential if you want to get the best possible finish when painting. We hope that this guide will guide you on how to thin and apply any alkyd paint on your chosen surface for a classy semi-glossy finish that will be long-lasting.