14 Ways How to Make Acrylic Paint Thicker: A Comprehensive Guide

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The great thing about acrylic paint is the fact that it is versatile to use, giving the artist a lot of room to experiment with it. Artists look for thickening mediums primarily to add texture to their artwork. If you are wondering how to make acrylic paint thicker, you have come to the right place. 

There are several thickening mediums you can use for your artwork. You can easily thicken acrylic paint by using modeling pastes and acrylic gel mediums. You may also use household items like flour, PVA glue, talcum powder, and cornstarch to thicken acrylic paint.

With acrylic paint’s ability to be thickened, you can play around with the paint’s different attributes. With several thickening agents available for you to use, you can create unique painting finishes or make a 3D painting with acrylic paint.

Why make acrylic paints thicker?

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It is typical for acrylic paint to have a thick consistency. A thick consistency allows the acrylic paint to be spread easily and for efficient blending of colors. However, adding a thickening agent to your paint will not necessarily make the paint dry up fast.

If acrylic paint generally has a thick consistency, so why the need to thicken it? The main reason why artists want to thicken their acrylic paint is that they want a specific texture, depth, or effect for their artwork.

They can achieve that only through manipulating the paint – thickening it. Also, you may need thick textured paint if you bought a thin acrylic paint brand.

How to Thicken Acrylic Paint at Home

You can thicken acrylic paint by using common household to make DIY thickening gel in the comforts of your own home, such as

  • Flour
  • Cornstarch
  • Baking soda
  • PVA glue
  • Joint compound
  • Talcum powder
  • Diatomaceous Earth
  • Baby Powder
  • Gelatin
  • Pectin

You don’t have to purchase expensive thickening agents. You can achieve the same thickening effect when you use common household items. If you are a beginner and still experimenting, you can make your own DIY paint thickener.

It is understandable to want to use inexpensive materials for your painting. However, being too frugal may have long-term effects. DIY acrylic paint thickeners (containing non-traditional additives) can eventually decay. 

DIY acrylic paint thickeners may work great for a while but your painting may not last for a long time. You must remember that there are disadvantages when you use these items. You may notice the change in paint color and texture.

Another downside is when adding water to your acrylic paint. These can cause the paste to crumble or create small lumps. You will struggle to create smooth brush strokes. If you are able to experiment with these agents beforehand, you would be able to manage your expectations.

Despite these concerns, you may still want to try making your own DIY acrylic paint thickeners. Thus, you will still end up feeling impressed with your artwork.

Here are some household items that you can use:

How to Make Acrylic Paint Thicker With Joint Compound

How to Make Acrylic Paint Thicker

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A joint compound can be an inexpensive alternative acrylic paint thickener. It mixes well with paint and dries fast. This is available in most hardware stores.

A joint compound can be used to thicken acrylic paint. However, when mixed with acrylic paint it has the tendency to crack when used on canvas. It also has the tendency to lighten the color of acrylic paint.

How to Make Acrylic Paint Thicker With Pva Glue or Talcum Powder

If you are looking for a quick fix and you want to thicken your acrylic paint ASAP, you can rely on PVA glue and talcum powder to do the trick. 

If you want to use talcum powder, combine talcum powder with acrylic paint in a mixing bowl. The more talcum powder you add to the mix, the thicker the paste will be. Using talcum powder creates a semi-matte finish. This will make your acrylic paint look dull and crumbly.

Talcum powder can be a better thickening agent when it is paired with PVA glue. With an initial ratio of 1:1, mix these 2 ingredients together. If you want the mixture to be thicker, add more talcum powder. If you achieve the desired consistency, you can add the mixture to acrylic paint.

However, there is a downside when using these items to thicken acrylic paint. When using them you may notice the paint’s color to be less vibrant and greasy. 

The paint has the tendency to crumble when it dries. Using these items may not be the best idea, but would do during emergencies and in small quantities.

How to Make Acrylic Paint Thicker With Baking Soda

Baking soda can be used to thicken acrylic paint. The great thing about baking soda is the fact that it will not cause any chemical reaction when mixed with acrylic paint.

However, adding baking soda to acrylic paint can make the paint dull. Avoid using baking soda as a DIY paint thickener if you are planning to paint miniatures or artworks that demand a glossy finish.

How to Make Acrylic Paint Thicker With Flour

If you are looking for a plant-based and affordable alternative to commercial acrylic paint thickeners, flour is your best bet. Flour is also used to make paper mache. 

When you use flour, it produces an almost similar effect when you use thickening gels for acrylic paint. In making a thickening paste with flour, you need water, a cooking pot, and a stove. 

In a cooking pot, mix water and flour (ratio of 2:3) and let the mixture heat up until you achieve the thick consistency you are looking for. Continually stir the mixture. 

If the mixture is not thick enough for you, you can continue adding more flour. If you are satisfied with your paste, turn off the heat and let the paste cool down.

Once cooled, you may gradually add the paste to your acrylic paint. You can store the excess paste in an airtight container and place it in a cool and dry place.

A disadvantage of using flour as a paint thickener can make the paint coarse and textured. Using flour as a thickening medium will not make your paint last very long. 

Flour has the tendency to have a gummy texture because of the activated gluten. It can also eventually flake, crack, and become brittle over time. To do away with a gummy texture and other issues when using flour, It is advisable to use gluten-free flour

How to Make Acrylic Paint Thicker With Cornstarch

Like flour, cornstarch is also plant-based, eco-friendly, and a cheap alternative for thickening acrylic paint. Cornstarch is used to thicken your soup or gravy in the kitchen. Thus, it can also thicken acrylic paint. 

However, as a word of caution, there are disadvantages when using cornstarch in your acrylic paint. When you use cornstarch for acrylic paint, molds or mildew can grow. To reduce the possibility of mildew growth, it is recommended to apply a clear sealer over your artwork. 

Also, using cornstarch has the tendency to give acrylic paint a gooey effect which can be very challenging when you mix or blend colors. Cornstarch can also affect the water-resistant ability of acrylic paint.

The process of making a thickening paste using cornstarch is similar to the process mentioned above when using flour. Though, the measurement for the mix would be different, 2 cups of water and 3 tbsp of cornstarch. You will need to heat up the cornstarch and water mixture to form a thickening paste.

Cornstarch and flour have almost similar properties, thus you can expect the same challenges when you use them as thickening agents for your acrylic paint. If you opt to use these items, it is advisable to experiment first so you can manage your expectations.

You can still make acrylic paint thicker without cornstarch. You can use other household items instead. You can use flour, PVA glue, talcum powder, joint compound, and baking soda.

Using Diatomaceous Earth as Acrylic Paint Thickener

Diatomaceous earth is an inexpensive choice for acrylic paint thickener. These are resistant to cracking and can create a uniform sheen to your artwork. Diatomaceous earth can make acrylic paint more durable. It is also a good matting agent for a glossy finish. 

You can initially create a small mixture of the diatomaceous earth (¼ cup) with water (2 tbsp) and acrylic paint (½ cup). Keep mixing thoroughly until you have reached your desired consistency. 

You may want to minimize using diatomaceous earth because this can cause irritation to your respiratory system, eyes and skin. You may end up with a cough or experience shortness of breath. It can also cause irritations to your eyes and skin.

Using Baby Powder as Acrylic Paint Thickener

Baby powder can alternatively be used as an acrylic paint thickener. You can create a paint thickener by following the steps below:

  1. Add 2 tbsp of baby powder with 1 cup of acrylic paint in a bowl.
  2. Mix the two ingredients together until you reach the consistency you desire.
  3. If you made a mistake and the paint becomes too thick, you can gradually add water and mix thoroughly using a paintbrush, palette, or stick.
  4. You can now use your paint mixture for your artwork.

Using Gelatin as Acrylic Paint Thickener

You also have the option to use gelatin as an acrylic paint thickener. Below are the steps on how to make a gelatin paint thickener:

  1. Add 2 tbsp of gelatin powder with 1 cup of acrylic paint in a bowl.
  2. Mix the two ingredients together until you reach the consistency you desire.
  3. If you find the paint is too thick, you can gradually add water and mix thoroughly using a paintbrush, palette, or stick.
  4. Allow the mixture to sit for 15 minutes to ensure that the gelatin has fully dissolved.
  5. You can now use your paint mixture for your artwork.

Note: Expect the mixture to be a bit sticky to use.

Using Pectin as Acrylic Paint Thickener

Another household item that you can use to thicken acrylic paint is pectin. Using pectin, you can make an acrylic paint thickener by following the steps below:

  1. Add 2 tbsp of pectin with 1 cup of acrylic paint in a bowl. Pectin is a natural thickener so you can make adjustments with the measurements as you see fit.
  2. Mix the two ingredients together until there are no visible clumps. Mix until you reach the consistency you desire.
  3. If you find the paint is too thick, you can gradually add water and mix thoroughly using a paintbrush, palette, or stick.
  4. You can now use your paint mixture for your artwork.

What can I add to acrylic paint for texture or impasto?

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First of all, what is impasto? The impasto technique is an expressive painting technique where the paint is applied on the canvas thickly. You will be able to notice the brush or painting knife strokes because of the thick paint. 

When the paint is dry, it would seem that the paint is sticking out of the canvas. Thus, you would need to know how to thicken your acrylic paint when adding texture to your artwork. There are 5 mediums that you can use to create texture or impasto to your artworks.

Gel Medium

Heavy body paint gels mixed with acrylic paint can thicken it. With much thicker paint, you can expect richer and thicker textures with every brushstroke.

Impasto Medium

Impasto mediums are used best to thicken oil-based paints. Impasto mediums are made from silica, ground calcite, and bentonite.

Impasto medium dries quickly and evenly with a glossy finish. This medium when mixed with paint doesn’t crack or wrinkle. 

Oleopasto Mediums

The oleopasto medium not only adds texture to your paint or gives it extra body, but it can also make the paint dry quicker. When the paint mixed with oleopasto medium dries, it doesn’t shrink or collapse. Thus, you are not wasting any paint in the process.

Glass Beads

Glass beads gel mediums are made up of small glass spheres which can thicken your acrylic paint. These small glass spheres are transparent and translucent. These can be applied directly to the canvas or mixed with paint.

Opaque Flakes

You can use Opaque flakes or white flakes to thicken acrylic paint. This flake medium stretches your acrylic paint allowing you to use lesser paint from the tube. With a fewer amount of paint, you can still produce a rich impasto effect on your canvas.

How to Make Acrylic Paint Thicker on Canvas

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There are several traditional ways you can thicken acrylic paint on canvas. You can thicken acrylic paint by adding modeling clay or paste and acrylic gel mediums. You can also use gesso, a paint primer to thicken acrylic paint.

If you have an extra budget to spare, it is best to use commercially-sold thickeners that are made specifically for acrylic paints. They contain similar manufacturing ingredients and resins. 

These paint-thickening mediums give you more control and transparency with your artwork. You will see that your painting will not break down and will last longer when you use thickeners such as modeling paste and acrylic gel.

Always read the label whenever you buy a thickening medium. Check whether it has a glossy or matte finish. Also, check whether the medium can alter the color of your acrylic paint.

Modeling Clay or Modeling Paste

Modeling paste is a great choice to thicken your acrylic paint to create 3D artwork. A modeling paste can help you create a very thick paint that looks raised giving the painting texture and a mesmerizing effect.

The modeling clay is a thick white paste that you can mold to create your desired texture. It is a viscous paste made with acrylic polymer emulsion and marble dust. You can create 3D patterns with your paint by coating acrylic paint with modeling paste and applying the paint to your canvas. 

Another way of using modeling clay is by first applying the clay directly to the canvas and creating the pattern you desire. Once the clay or paste has dried, you can apply acrylic paint over the textured paste to make a 3D effect or illusion.

The downside of mixing or coating acrylic paint with modeling paste is the fact that it can reduce the vibrancy of the paint color. On the other hand, if you mold the paste directly on the canvas, it can retain the color vibrancy of your acrylic paint. 

Overall, using modeling paste is a cost-effective way of thickening acrylic paint. The paste is really thick and easy to mold. You will be easily satisfied with the results if you use modeling paste.

Here are the steps on how to mix modeling clay with acrylic paint:

  1. Prepare your working area with a firm board and palette knife or an art brush with firm bristles. You will also need a bowl for mixing.
  2. Squeeze out the acrylic paint from the tube or tub onto the bowl. Gradually add modeling paste to the mix. The mixture should contain 1 part modeling paste and 4 parts acrylic paint. Mix thoroughly with a palette knife or putty. You can stop adding modeling paste if you are satisfied with the consistency you have made.

Note: Avoid adding so much modeling paste to your paint for this can make it unstable.

  1. Quickly mix the paint with the modeling paste. Adding a thickening medium to acrylic paint makes the drying time of acrylic paint faster.
  2. If you made a mistake with the modeling paste, you can easily wipe it off or scrape it off with a palette knife while it hasn’t dried yet. 

If you want to do a different approach and apply the paste on the canvas first, then here are the steps to follow:

  1. Prepare your working area with a firm board.
  2. On the firm board, distribute and sculpt the modeling paste into patterns that you like for your artwork. 
  3. Position these patterns onto your canvas.
  4. Once the paste dries completely, you can begin painting over the patterns with acrylic paint.
  5. You must remove the pattern from the canvas as soon as you make a mistake. Don’t wait for the paste to dry on the canvas. If you let this happen, you would be spending precious time scraping the paste off with sandpaper. 

Acrylic Gel Medium

Another traditional method of thickening acrylic paint is by using an acrylic gel medium. Like the modeling paste, the gel medium is also thick, creamy, and white in color. 

However, once the gel medium dries, it has a clear finish while the modeling paste remains white when dry. The gel is soft and round, unlike the modeling paste which is more solid and flat.

The best thing about acrylic gel medium is choosing the finish (gloss, matte, and semi-gloss) you would like. It is best to read the packaging label to know the gel finish before making your purchase. 

The notable difference between the two is that mixing the gel with the acrylic paint will not reduce its color vibrancy unlike with the modeling paste. A downside of using the gel medium is the fact that it has a tendency to shrink when it dries. Thus, the application of more layers is necessary.

Like the modeling paste, you can apply the gel medium in 2 ways. First, by mixing it with the paint and second, by applying it onto the canvas before applying paint over it. The steps on how to mix acrylic paint with modeling clay are almost similar to acrylic gel medium. Thus, you can refer to the steps indicated above.

If you choose to apply the gel onto the canvas first, you can also refer to the steps indicated above as well. However, when using gel medium, you need to apply as little as possible onto the canvas. 

Applying too much gel medium can make your patterns lumpy or chunky. Thus, this can be a challenge when you apply paint over it when it dries. If you are encountering problems with chunky acrylic paint, refer to this article on how to fix it.

Here are 7 types of acrylic gel mediums that you must be familiar with to help you in choosing the acrylic gel that you will use for your artwork:

Acrylic Gel MediumCan produce a well-thickened acrylic paint?
Soft Acrylic GelNo
Regular Acrylic GelYes
Heavy or extra heavy Acrylic GelYes
Semi-gloss Acrylic GelYes
Gloss Acrylic GelYes
Matte Acrylic GelYes
Textured Acrylic GelYes
  1. Soft Acrylic Gel

If you are looking to incorporate a transparent glaze into your artwork, a soft acrylic gel is a good option to use as a paint thickener. However, you won’t be able to create impasto paintings with this gel medium. Neither will you be able to see your brush strokes or make sharp palette knife markings.

  1. Regular Acrylic Gel

A regular acrylic gel cannot make your acrylic paint thicker. Rather, it will aid in making the paint more transparent without losing its thickness in the process. Using this type of acrylic gel can help you create patterns with your palette knife such as sharp edges and high peaks.

  1. Heavy or Extra Heavy Acrylic Gel

Heavy or extra-heavy acrylic gels are thicker than oil-based paints. These acrylic gel types can be directly applied to your canvas with your palette knife or putty. You can create high peaks and sharp edges with these acrylic gel types.

  1. Semi-Gloss Acrylic Gel

If you are going for a more balanced finish for your artwork, you would want to use a semi-gloss acrylic gel medium. A semi-gloss effect is created when the matte and gloss acrylic gels are mixed together.

  1. Gloss Acrylic Gel

The gloss acrylic gel not only thickens your acrylic paint but also gives your paint colors more vibrancy. Using a gloss acrylic gel you create thin brush strokes for highlighting effects.

  1. Matte Acrylic Gel

Not only does the matte acrylic gel thicken your paint, but it also produces a non-reflective finish to your acrylic paint. Acrylic paint generally has a glossy finish. Using the matte acrylic gel, you can remove the paint’s glaring effect.

  1. Textured Acrylic Gel

If you want to thicken your acrylic paint with some texture, you can add the textured acrylic gel medium to your acrylic paint. Textured acrylic gel medium easily is shaped and adheres well to the canvas. 

Gesso

Aside from being a paint primer, Gesso can also be added to acrylic paint to make it thicker.  When choosing a brand to use, do check the packaging label to ensure that you are getting a gesso with a much thicker consistency.

There are Gesso brands that are best used as a primer only while there are some brands that can be used both as a primer and can be an acrylic medium to make the paint thicker.

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Using gesso is simple. All you need to do is gradually mix gesso with acrylic paint until you achieve the desired thickness. Then, you can create different patterns or textures for your artwork.

Spackling Paste 

Many artists have used spackling paste as an inexpensive alternative to modeling paste as an acrylic paint thickener. Though, there is little information about how effective it will be to your artwork long term. 

Those who have used this medium have noticed the paste has the tendency to shrink and crack. It is understandable to have doubts about using this as a paint thickener. However, there is always room to experiment with spackling paste. 

If you want to try it out with acrylic paint, gradually mix the spackling paste with paint until you have reached your desired consistency. You can expect a color shift when spackling paste is mixed with paint. To retain the paint’s color, it is advisable to apply the paste directly on the canvas and paint over it when it dries.

How to thicken acrylic paint FAQ

Why is my acrylic paint so thin?

Your acrylic paint is probably thin because of how it was manufactured. Less pigment and filler were used to make the acrylic paint. Acrylic paints that are so thin are poor-quality paints. Acrylic paints are generally thick enough so they can easily be mixed or blended.

If you are curious about how to thin acrylic paint or if you need to thin acrylic paint for your painting, you can refer to this article on how to thin acrylic paint. Or if you have problems with watery paint, you can give this article a read.

What medium makes acrylic paint thicker?

The mediums you can use to make acrylic paint thicker are acrylic gel medium, modeling paste, and gesso. Though, many art enthusiasts prefer to use acrylic gel medium because it retains the paint’s color vibrancy and the paint’s adhesive properties.

How do I make cheap paint thicker?

Cheap paints usually have a thin consistency, thus would need to be thickened. You can always make a paint thickener using common household products such as flour and cornstarch. For best results, it is best if you can use commercially sold modeling pastes or acrylic gel mediums to thicken the paint.

What can I put in paint to harden it?

You can easily harden or solidify paint by adding commercially sold paint hardeners. Aside from paint hardeners, you can add sawdust or even cat litter to your paint to harden it. Mix these well with your paint and wait for the paint to completely harden after a few days.

Conclusion

If you find yourself using thin acrylic paint, don’t throw it away. Don’t throw away good paint just because it has a thin consistency. You can still remedy the situation by thickening it.

Acrylic paint is a well-loved paint medium by many art enthusiasts primarily because it is affordable, flexible, and convenient to use. Not only is this paint quick drying, but the finish can also be altered by adding a medium.

There are thickening agents that you can buy such as modeling pastes and acrylic gels. You also have the option to make your own DIY acrylic paint thickeners using household items like flour and cornstarch.