Skip to Content

How to Rehydrate Acrylic Paint: 14 Good & Bad Ways To Soften Acrylics

By Author Masha Eretnova

Posted on Last updated:

Acrylic paint is an easy-to-use, versatile, and, most importantly water-soluble paint.

Yet, you may store some paints and later find out dried-out acrylic paints. If this happens to you, learning how to rehydrate acrylic paint is the solution.

Even though acrylic paint is water-soluble you can only rehydrate acrylic paint that has some moisture and is still glossy. You can dilute acrylic with warm water or acrylic flow improver. Once acrylics dry you cannot rehydrate or reactivate the paint.

This article will guide you on rehydrating dry acrylic paint and even prevent it from drying out. Read on to save the dried-up paint!

I will go over easy methods, some risky DIY ways, and extra tips for keeping paint from drying.

I will be honest with you and tell if I think it is a good or bad method to try.

How to Rehydrate Acrylic Paint

Why is my acrylic dried out or hard?

Acrylics are water-based with pigments floating in resin. The evaporation of water causes the acrylic to dry and form a plastic-like film on the surface.

This process makes acrylic paint water-resistant and not washable and it takes only up to 30 min.

Reasons why you have hardened acrylic paint:

  1. The old paint was exposed to a lot of air. This effect also takes place when you forget to put the lid back on.
  2. Direct sunlight or extreme temperature (both cold and extreme heat) gets into the area where the paint is stored.
  3. You may have failed to mix the paint properly before use.
  4. An excessive amount of water was added to the paint before application.
  5. Putting too much paint on the palette as acrylic paint can dry in just a matter of 10 to 20 minutes.
  6. Paint with low quality will likely dry out even if it’s still in the paint container as it has a meager amount of pigments and no-name binders.

How to rehydrate acrylic paint (all methods upfront):

  1. ✅ Warm water
  2. ✅ Fluid medium
  3. ❌ DIY flow aid medium (risky, I do not recommend, but people still do it)
  4. ✅ Flow improver
  5. ❌Toothbrushing dried paint with water or alcohol (risky, I do not recommend it, but people still do it)
  6. ❌Add oil paints (risky, I do not recommend it, but people still do it)
  7. ❌Add acetone (risky, I do not recommend it, but people still do it)
  8. ❌Household Method with soda (risky, I do not recommend, but people still do it)
  9. ❌Microwave (risky, I do not recommend, but people still do it)
  10. ❌Add fresh paint and mix in a blender
  11. ✅ Sanding (to fix dried paint on canvas)
  12. ✅ Glazing liquid
  13. ✅ Gesso
  14. ✅ Pouring medium

So ultimately, most of the DIY methods recommended online won’t work. I understand people said it worked for them, but if we truly understand the composition of acrylic (polymer, pigment, preservatives, water) we won’t add a dishwasher to it and expect it to be artist-grade brand-new paint.

Let’s stay rational, my friends!

Let’s look at each method in detail and you can decide for yourself whether to try it or not! If you tried something else and it worked, email me!

How to rehydrate acrylic paint if it is too hard/thick

Photo credit: source

Don’t lose hope when you see your acrylic paint that turned dense, and heavy. There’s a chance to revive it with warm water and a flow improver as long as the paint has a little moisture in it.

This method also helps if you think you have thick heavy body paint and you want to make it more fluid.

1 – A drop or more of warm water

Warm water is like a magical potion in restoring acrylic paint that turns hard and clumpy. It doesn’t only work wonders but it doesn’t thin out the paint. The temperature of water improves the paint’s solubility.

After adding a drop of warm water, stir the paint with a small toothpick or a wooden stick. If you feel it is not enough, add a little more water.

It’s best to let it sit overnight and check the outcome the following day. Before you leave it, make sure that the pods are tightly sealed to prevent air from messing it up.

Read also: How to Thin Acrylic Paint: 3 Correct Ways & 3 Dont’s

Make sure to not add more than 25-30% of water to your paint,if you will add too much water you will end up with watery paint.

This method may not work with fabric acrylic paint.

2 – Flow improver

Using a flow improver is one way to put hardened or thick acrylic paint into use. Unlike warm water, flow aid mediums don’t break acrylic paint composition and only improve the consistency.

You can directly mix it with paint or prepare a cup with water to wet your paintbrush and put a few drops of flow improver in it. This is done before you start painting.

The Max ratio is 25% of flow aid to paint.

Dip your brush into the cup then into your paint.

You’ll notice that the brush moves smoothly over the painting surface. But you should be aware that flow improver thins the paint and it may turn more transparent.

If these methods didn’t work your paint is not just thick, it started to really dry out, the hard paint doesn’t have a bit of moisture left.

Read also: How to Fix Lumpy & Chunky Acrylic Paint? [10 Easy Methods]

7 Ways How to Rehydrate Dried-Out Acrylic Paint

There are several ways to rehydrate drying acrylic paint that still contains some moisture. Drying paint may become lumpy and rubbery, it will spread unevenly on the painting surface. 

Sometimes you can fix it by mixing it well with a palette knife, but if it doesn’t work, check one of the methods below.

3 – Add fluid acrylic medium

The simplest way of rehydrating acrylic paint is by adding a liquid acrylic medium. Liquitex offers archival matte or gloss fluid mediums that help improve the blending and flow of the paint.

You can start with a small amount of paint and mix the medium. You should know that this mixture makes the color more transparent compared to the original pigment. Don’t add more than 1/4 part to 1 part of the paint.

4 – Water or alcohol with a toothbrush

Normally, you should avoid thinning water-based paint with alcohol. But some crafters report that it helped rehydrate dried paint. I would first try the same with water.

You need isopropyl alcohol (50% to 99%) and an old unused toothbrush.

  1. Dip the toothbrush into the water or alcohol. It would give you 20 to 30 drops of the said liquid which is enough for 100 ml of paint.
  1. After adding water or alcohol, gently rub the brush to encourage rehydration. The goal is to make the paint spread evenly on the surface during application.
  1. When rehydrating dried acrylic paint, you have to pay attention to its consistency. That’s why you have to gradually add water. Excessive amounts can make the paint weak. It leads to blooming, an effect where you can’t control the spreading of the paint on the canvas.

Alternatively, you can just add a few drops of isopropyl to your paint jar, and then add warm water. And mix it with a wooden stirring stick.

5 – Making a mixture with oil paint

Another DIY and risky method, that still exists out there, is to add oil paint.

Well, normally, mixing oil and acrylic is a bad idea as we all know it is practically impossible to mix oil and water, one will sit on top of the other, so the mixture will be separated inside the container.

Yet, my fellow crafters successfully restored the body of the acrylic paint with oils. But you have to know that the colors of the acrylic paint will change once you add the oil paint.

6 – Acrylic glazing liquid

If you want to add gloss and rehydrate your acrylic paint at the same time, get acrylic glazing liquid. It is primary function is to extend the drying time which is exactly what we need!

Liquitex and Golden both have great options in satin or gloss finishes.

You’ll only need a small amount of this liquid to revive your dried paint – 1/4 part max. In addition, you have the liberty to add more if you want to intensify the color or the gloss. 

7 – Gesso

Gesso is mainly used to prime canvases and it is a white, grey, or black thin medium. Gesso is akin to white acrylic paint but it’s on the thinner side.

Put some of the drying paint on the palette and some amount of gesso. Mix so you can come up with the texture that’s great for painting. 

8 – Home-made flow aid

You’ll need: rinse aid liquid dishwasher and distilled water

  1. A half teaspoon of the dishwasher and a small amount of water should be mixed properly.
  2. Combine this mixture with the dried paint and stir them gently to achieve an even texture. 

Yet, I would like to say that this is 100% DIY and I would not recommend it to use with artist-grade expensive paints or for paintings you are planning to sell.

Simply because nobody can guarantee how durable this mix will be after it dries.

9 – Pouring medium

Pouring medium reduces the tension and makes acrylic paint fluid and durable. There are dozens of pouring mediums on the market, from well-branded Floetrol to glue-based affordable Mont Marte pouring medium.

Each pouring medium has its own best ratio for mixing pouring paint, but we don’t need to follow it as we are not creating easy-to-flow paint, we simply need to rehydrate our dried acrylics.

Start by adding a few drops and not more than 25% of the pouring medium to the paint. Unless you really want to make it flow.

10 – Household products

You will need regular odorless hand sanitizer, little bit of warm water, and little bit of baking powder.

Mix it well with paint, I would add water last.

2 Methods on How to soften hard acrylic paints in Tube

Acrylic paint may not only be dried out on the palette but it rarely can dry out in the tube.

The most common reasons are improper storage, lid not tightly closed, or short shelf life of poor quality paint.

To be honest, I would buy new paint, but you can still try to save it with some experimental methods:

11 – Mix Fresh and Dried acrylic paint and a blender

Yes! Fresh acrylic paint can be mixed with the dry one but you’ll need a blender. Only mix the same brand, as you don’t know exactly the composition of all brands and how they will interact.

You will need an airtight container where you can store newly mixed paint.

  1. Cut the tube to access the dried paint.
  2. Break the hard acrylic paint into chunks.
  3. Put the fresh acrylic paint into the blender before the hard chunks. This is to ensure that no chunks can be missed by the blender and that the color becomes smooth.
  4. Add a little amount of water for dilution and blend to even out everything.

12 – Microwave

Yes, some crafters came up with this idea. I would not guarantee that it will work and the acrylic paint will definitely lost its archival qualities if you will put it in heat.

If you are risky, you can try:

  1. Cut the tube
  2. Transfer dried paint to the microwave-safe container
  3. Add a little bit of water
  4. Microwave for 30 seconds and stir.

13 – Acetone (Risky)

If the acrylic paint is hard as a rock, you need acetone, a kind of thinner. This substance can soften dry, hard acrylic paint. Due to its alcoholic content, acetone can gradually break down thickened substances.

But you don’t want your hard chunks of acrylic paint to completely dissolve, make sure you follow the 1:3 ratio of acetone to acrylic paint which is enough to soften the dried paint. 

  1. Once you have followed the recommended ratio, you can place it in a container to shake or stir. Give it some time until the mixture turns into a thick, evened-out substance.
  2. Thoroughly mix the two substances up to the bottom part of the container. You have to avoid having some parts thinner than the others.
  3. You should know that the alcohol content in the acetone speeds up the drying of acrylic paint even if it’s in storage. Store it in an open area or somewhere with good ventilation. Your acrylic paint shouldn’t be exposed to temperature after adding acetone. Again, it’s to prevent the paint from drying in no time.  

Yet, as with alcohol, acetone and other solvents are not ideal for acrylics. I would not risk it, but I know that crafters still do that.

How to fix dried paint on a canvas

Making a mistake on a canvas is inevitable and it even happens to the most experienced and cautious individuals.

Acrylics are fast-drying and sometimes 10 minutes is not enough to do what you want and you may end up with dried paint on canvas.

Acrylics cannot be reactivated simply with water.

Unfortunately, if you have a few dry layers of acrylic paint, there is not much we can do, but sanding may actually work perfectly!

The easiest is to try and cover up some mistakes with accents or new thin layer. The most desperate method, if the area that needs to be fixed is to big, you may have to scrape the painting completely.

Read also: How To Fix Cracked Acrylic Painting in 3 Easy Ways 

14 – Sanding

You’ll need:

  1. Make sure the painting is completely dry.
  2. Put a small amount of denatured alcohol on a paper towel. Fold the towel into a suitable size. Wipe the intended section of the canvas and wait until the alcohol softens the dried paint so you can correct mistakes.
  3. Once it’s dry, sand the area lightly to create a rough texture for the paint to cling on. Since you’ll be exposed to sanding and alcohol, put on a mask so you won’t inhale any tiny particles.
  4. After sanding, use a damp cloth to get rid of the dust.
  5. When the corrected area is dry, you can begin painting.

How to Keep acrylic paint from drying out

1) Don’t forget to return the caps of tubes and containers 

Squeeze little bit of paint and immediately return the caps to the tubes and containers. They should be tight enough not to allow air inside.

Even 30-60 min without a lid can let paint dry out.

If you have leftover paint, and the lid on the tube isn’t working, transfer the paint into an airtight container and add little water.

Related: How Long Does Acrylic Paint Take to Dry? 30 Brands Drying Time

2) Having a covered workplace

The outdoor mood can inspire some people to paint. Sadly, elements like sunshine, air, and even occasional breeze easily dry up acrylic paint. Since you’ve been warned, you have to prioritize painting indoors in a well ventilated area.

Still, you may paint outdoors but within the specified time. To avoid direct sunlight, you can go out and paint in the early mornings or late afternoons.

3) Proper storage of paint

Proper storage makes a big difference in preventing your paint from drying out. You have to put your tubes, and jars or containers away from sunlight and high temperature. The ideal temperature when storing acrylic paint is from 21 to 32 degrees Celsius. In terms of humidity, it should not be over 75%.

The paint tubes should be stored vertically with their caps up. This manner will block the bubbles from forming in the paint.

If you store your paint in bottles, add balls in them. Mixing balls help evenly mix paint when you shake the bottle and make paint last longer.

4) Putting a small amount of paint on the palette

Remember that acrylic paint can dry up in a few minutes so just put a small amount of paint on the palette. This is how you can avoid wasting paint as well. You can always add and mix more later.

Keep your palette always clean.

5) Using helpful items

You can depend on some helpful items to prevent your acrylic paint from drying. They can save you time and effort by restoring dried paint. 

  • Stay-wet palette – This palette has a layer of absorbent paper that is equivalent to a water reservoir. There’s also a grease-proof paper that blocks water from mixing with the paint. You can buy one or make one.  

Please, always keep stay wet palettes clean and don’t soak it water. It can encourage mold growth and the palette can easily tear apart when using a palette knife. 

Read: 15 Proven Ways How to Make Acrylic Paint Dry Slower & Homemade Acrylic Paint Retarder Recipe

FAQ section

How to fix dry paint from your paint by number kit?

Paint by numbers kit includes acrylic paint in small cups with loose lids. But you’ll find some dry colors that can crack or flake. You can fix it with a drop or a little warm water. Another way to loosen the paint is to spray warm water. A brush or palette knife can help you scrape the dried paint on the sides.

Besides water, flow aid improver or thinners can be used to fix the dry paint from your paint-by-numbers kit.

A blow dryer can turn the paint into liquid, especially if you’re painting in a humid place. Give a 6-inch gap between the paint and the dryer. Let the heat from the blower work on the dried paint for a few minutes. It should be done before you start with your project and you may need to repeat it while you’re painting. 

Brands like MyPaintNumbers even offer to replace your dried paints.

Can you reactivate acrylic paint with water?

You can reactivate acrylic paint with water as long as it has a bit of moisture left in it. Adding water should be done slowly and no more than 1/3 of the volume of the paint.

But thin, dried layers of acrylic paint can’t be reactivated with water. That’s why it’s important to clean the palette after use.

What to do with old acrylic paint?

Acrylic paint can be kept unopened for 10 years. As mentioned, you can revive dried paint with water, a flow improver or fluid additive.

But some circumstances won’t allow it.

You cannot really see acrylic paint expire, but when the paint is opened and left unattended for 2 to 3 years, mold can develop or it will dry out.

Mold is not a good sign as it discards the moisture left in paint which is necessary for rehydration. If there’s no small amount of moisture in acrylic, you can’t revive it.

The presence of mold gives off a sour, mildew smell so you will be able to tell if the paint has gone bad.

Summary

Don’t lose hope when you feel like your acrylic paint paint is drying too fast. Be patient to rehydrate it with the help of warm water, a flow improver or fluid additive, and thinners like acetone.

You have to slowly add either of these substances in a small amount to end up with the desired consistency of the paint.

It’s also crucial to know if you can rehydrate dry acrylic paint or not.

Reviving is impossible if it has molds that eliminate moisture left in the paint.

To avoid this mishap, follow the tips to prevent your acrylic paint from drying out.