What You’ll Need

To get started with the process of removing acrylic paint from a canvas surface, you need to have the necessary products on hand:

The right solvent, to act as the cleaning solution
A soft cloth, to remove paint in smaller areas
A putty or palette knife, to scrape off any remaining paint
A container of varying size, to soak the canvas in
Dish soap, to complete the cleaning process
A soft brush, to rub any solution over the canvas
Acrylic gesso, to prime the canvas before applying any paint

Before You Clean, You Need To Understand What Acrylic Paint Actually Is & Isn't

First, acrylic paint isn't like watercolors, oils, craft paint, or even your standard latex paint (often confused with artist acrylic paint as it contains a similar chemical compound called acrylic resin).

Instead, acrylic paint is pigment suspended in an acrylic polymer emulsion.

This completely unique mixture gives it properties that you simply don't see in many other mediums.

Why is this important?

As you likely already know, when working with wet acrylics, it can easily dissolve in water (like when you go to rinse out your paint brush between color selection).

But as soon as you let the acrylic paint dry, small acrylic polymer spheres get tightly close to one another. Those few spaces left between them create capillary forces, with the water being pulled from the paint film.

What does this all mean?

Well the acrylic paint tightens and creates a cohesive film in a process called 'coalescence' where the acrylic paint literally pulls itself together.

Due to how cohesive this film is, water is not enough to remove any undesired paint. As such, you need something much stronger to make any changes to the painted area.

Enter solvents:

Safety While Using Solvents

Solvents work best to remove paint from a canvas but should be used with some caution. Once you have decided on which type of solvent you want to use, follow the tips below to avoid encountering any major problems.

Read the labels and instructions thoroughly before using them
Never use a solvent near open flames or heating elements
Avoid inhaling the solvent. It would be best if you can work outdoor, otherwise avoid closed spaces and ensure there is enough ventilation
Always wear gloves and protective eyewear when you are handling solvents to decrease exposure
Avoid mixing the solvents together, use them separately

When it comes to the proper solvent to use, artists in popular forums such as WetCanvas, Quora, and countless others have found a variety of solvents capable in getting the job done.

However, based on our research, we found the following to be among the most popular (and effective) ones you should consider for this project:

Turpentine
Denatured Alcohol (or Isopropyl Alcohol)
Odorless Mineral Spirits
Ammonia (in rare cases)

Now a word on caution when it comes to solvents.

Given that these are being used in an artist grade application - you will want to get solvents that were intended for such a case.

Trying to save a few bucks by going to your local hardware store and picking up their generic 'odorless mineral spirits' is not advised.

But why?

Well, these types of solvents found at hardware stores are usually full of nasty impurities and are designed to be used outdoors.

Not only can this cause adverse health problems (including severe headaches and respiratory issues), but when it comes to artist grade paints, they are often much too harsh.

So we advise you to go with a proper artist (either professional or student) grade solvent over the hardware store solvents.

For further reading on solvents, we invite you to check out our write-up where we compared how odorless mineral spirits and turpentine are starkly different.

How to Proceed

Start by inspecting the canvas and decide which painted area you want to remove.

Full Canvas Cleaning

For a cleaning process that involves the whole canvas, you'll need a big enough container that can fit all the surface. Once you have found one, make sure you take precautions by wearing rubber gloves and working in an area that is well ventilated.

In that container, you should pour a layer of either turpentine, mineral spirits, ammonia or rubbing alcohol (never mixing them together). It should be deep enough that it can adequately cover the entire surface.

Soak the painting in that solution for an hour.

Once the time is up, you can take it out of the container and grab a putty knife to easily scrape off any remaining paint. If it doesn't all come off, then repeat the process until the canvas is completely clean.

Spot Cleaning

If you only intend to remove paint in a specific spot, then use a soft cloth as your cleaning tool. Dip it into a solvent of your choice, then place it over the area where the paint has soaked.

Leave it there for as long as it dries and keep repeating that process until you see no more paint transferring to the cloth.

For greater precision when it comes to scraping the paint clean, use a smaller palette knife and chip away any acrylic paint that needs to be removed.

Final Cleaning

To complete the cleaning process, place the solvent aside and grab some dish soap. Drip a few drops of it over clean and warm water, then use a soft brush to rub it over the canvas.

Once you are done with the soap, thoroughly rinse it off with water until there are no more bubbles left. Leave the canvas to dry overnight before using it again.

Let's Be Honest, Staining Will Occur

Whether you laid down your initial coat(s) of paint in either a thick or thin layer, more often than not there will be some residual staining that occurs on the surface long after you are done cleaning the canvas.

Therefore, you will want to have acrylic gesso on hand (more on this in a minute) in order to hide any acrylic stain from seeping through when you place your initial wash for the next painting that you plan on doing with the surface.

Now if you are trying to get acrylic paint off of your clothes, then a stain removal stick will be a better pick as it won't break down the natural fibers as opposed to some of the other harsh solvents mentioned in this article.

Painting Preparation For The Fixed Canvas

Most canvases purchased online or from a store come pre-primed with gesso.

However, if you decided to submerge your entire surface in a solvent mixture, much of this initial primer has likely been stripped from the canvas threads.

Lucky for you, re-priming your surface is fairly easy when you follow these 3 simple steps:

Pick up a quality gesso
Get a large brush (quality here isn't that big of a deal - a standard house paint brush usually works)
Apply to the surface in crossing layers (i.e. vertical, horizontal, vertical, etc.). Make sure you let the gesso fully dry between layers.

The amount of layers you apply to the surface largely depends on personal preference.

However, we like to recommend going with at least 3 layers of gesso.

Why?

This provides ample tooth and texture for your paint brush to latch onto the surface effortlessly.

Should you find that the layers may be a bit too thick - then a simple fine grit sandpaper can thin down the surface to your desire.

Due to the importance of applying quality gesso to the canvas, even beginners should consider buying the type of gesso used by professionals.

Brands such as Liquitex, Grumbacher, Golden Acrylic Gesso, and Winsor & Newton are a few that come to mind.

Check out our full review of all the popular gessos here.

Other Ways To Clean Dry Acrylics Off Canvas

Using solvents is the most common way to remove acrylic paint off a canvas but it's not the only one. Artists have discovered a variety of different methods to do this task, which require different levels of expertise. Not all of them are guaranteed to successfully clear the canvas, so try them out at your discretion.

Acrylic / Artist Specific Products

Use Atelier Artists' Acrylic's products to clean the paint off. Most specifically, their Unlocking Formula. By spraying the section of the painting you want to edit with it, you will rehydrate the surface and can keep blending.
Instead of removing the paint from the canvas, you can try to lightly sand the surface and then prime it with gesso.
Clean the canvas with the Turpenoid Natural solvent, which is citrus-based and non-flammable.

Do-It-Yourself Solutions

Lay the canvas down and pour a generous amount of Purell hand sanitizer (without Aloe). Let it sit and once it softens, wipe it with a damp cloth.
Dissolve the paint by spritzing products such as Oxyclean or Mr. Muscle Oxy. Let it stand for about 60 seconds or more, then scrape it off. If any paint remains, repeat the process.
If you have a nail polish remover that doesn't contain additives, then you can also use it to remove paint.
For those stubborn areas of paint that won't go away, you can try using an electric eraser.
If you are looking to just get a canvas surface clean and don't mind if it gets a little roughed up, a sharp razor blade (the old school kind) or simply a flat razor is an effective way at scraping the paint clean - just be sure to have a steady hand!
Tough on stains, gentle on skin - that's the famed slogan of one laundry detergent company. You can put that to the test when trying to remove some lighter acrylic paint stains on a botched canvas. We recommend that you use this in tandem with a rough bristle brush (such as a toothbrush) for more effective and deeper results.
A bit more abrasive than your standard laundry detergent, a liquid dish soap is another great way to penetrate the acrylic and canvas at a much deeper level. Like the laundry detergent, make sure you use an old toothbrush (or similar abrasive brush) in order to get a much more focused and deeper clean in your work.

Know When To Cut Your Losses

Throwing out a canvas is always the last resort.

However, to avoid situations where mistakes may cost you an entire canvas, we recommend that if you are still in the beginning stages of your artistic career and you are still trying to find own style, then a traditional stretched canvas may not be the best surface for you.

Instead of paying a high price per surface, especially when it comes to stretched canvases, you should instead take a look at alternative surfaces such as either canvas panels or simply a canvas pad.

These alternatives are much cheaper while still giving you the same texture to practice on.

Conclusion

Overall, the fast drying time of acrylic paint won't stop you from being able to remove it from a canvas. There are different ways one can try to clean the surface, with solvents being the most common and effective.

Whichever method you plan to try, always remember to take precautions when handling cleaning solutions, and to do this process in a ventilated area.

Once you obtain all the products you need and prepare both the canvas and yourself to use them, it's only a matter of time before you will have a fairly clean surface to paint over.