If you are like me, there is nothing worse than making a beautiful acrylic pour, letting it dry overnight, and waking up to find that your masterpiece has been ruined by cracks.
Paint crazing is something that usually happens to beginner artists, however, even experienced artists can get cracks in their paintings. But that doesn't mean that there isn't anything you can do to try to prevent cracks from happening.
So let's take a look at some of the things you can do to minimize crazing or cracking and how to fix them in acrylic pours in case it happens to your favorite painting.
What is cracking and crazing in an acrylic pour?
First, let's talk about the difference between cracking and crazing in an acrylic pour.
Crazing is a term used in acrylic pouring to describe the cracks, crevices, or tears in the surface of the acrylic pour that usually happen as the painting is drying. When acrylic paint starts to dry, a thin film starts to form on the surface of the painting. As the acrylic film continues to dry, it starts to shrink and this creates tension on the surface. If the film is not stretchy enough (because the integrity of the paint was tampered with), the stress from the shrinking will cause the film to tear.
Take a look at the following video to see what crazing looks like.
Cracking can be defined as crisp breaks on a previously dried and smooth surface of an acrylic pour. These cracks happen when a dried, rigid paint layer is flexed more than it's bending capacity. These cracks also run more deeply in the paint rather than just being on the surface.
For example, these cracks can happen if you take the canvas off the frame and roll it up or sometimes just by pushing too hard on the canvas surface after the paint has dried. It technically happens when you bend the canvas surface too much after the paint has already dried with a smooth finish.
Both crazing and cracking are therefore caused by imposing some sort of stress on the painting surface, however, crazing is the most common issue in acrylic pouring.
Therefore, in this article, I will be talking about how to prevent crazing. Just be aware that I might use the word crazing and cracking interchangeably.
How Do You Keep Acrylic Paint from Crazing?
Now that you understand what crazing is and why it could happen, let's talk about how to prevent it! Take a look at the following suggestions.
1) Reduce the amount of water in your paint mix
Adding too much water to your acrylic paint can break down the binding agents in the paint and also increase the amount of shrinking that will occur in the drying process. Therefore the stress in the film will increase and cause it to break.
Most quality brands of paints can tolerate up to 30% water, however, you will have to use a lot less water for cheaper low quality paints. It is better to use a pouring medium rather than water if you need to make your acrylic paint more fluid which brings us to our next point.
2) Use a pouring medium
There are many pouring mediums that will help make your acrylic paints more fluid without tampering with the integrity of the paint. There are even some pouring mediums made specifically to help prevent crazing such as GAC 800.
Yes, the GAC 800 is kind of expensive to use on it's own, so a lot of acrylic pourers add just a little bit to their own pouring medium recipes. For example, I like to add 1 oz of GAC 800 to 15 oz of Floetrol. Some people mix 50% GAC 800 with 50% Floetrol. Others use pure GAC 800 as their pouring medium.
Since GAC 800 is thinner than Floetrol, it helps make the paint mixture more fluid without needing to add too much water.
So if your acrylic paint is crazing, then try adding some GAC 800 to your pouring mixture.
3) Work in a controlled environment
Temperature, humidity, and air draft fluctuations can also cause acrylic paint crazing.
So avoid working in a room that is too hot or too cold. According to Golden Artist, the best temperatures for paints to dry are between 65°F-75°F (18°C-24°C). If the temperature is above 75° F, then the surface of your painting will dry much faster than the layers underneath which will cause some crazing.
The room you are working in should also have a Relative Humidity above 50%. If the air in the room is too dry, the water from your paint will evaporate faster and speed up the drying process while causing some cracking. So you could try drying your paintings in a room with a humidifier or difuser to increase the humidity in the room. Just make sure you don't increase the humidity beyond ~75%.
Also, avoid putting your artwork close to any air drafts. Don't turn on any fans in the room and don't put your artwork close to any air conditioner vents. The air from the fan or air conditioner blowing directly onto your artwork can cause crazing as it makes the top layer dry faster than the bottom layers. Also, make sure to close any windows and doors to keep the air movement to a minimum.
If your painting is drying too fast, it will crack. So in addition to the tips above, you can also add a retarder to your pouring mixture. This additive will slow down the evaporation process and therefore slow down the drying time of your paint.
One last thing I recommend is to cover your painting with a box or plastic container. The box will not only reduce the airflow and retain the humidity as the paint dries, but it will also help any unwanted hairs or bugs from landing on the surface of your painting.
Watch this video from Caren Goodrich which shows some excellent hacks to cover your paintings.
4) Use High Quality Acrylic Paints... Specially for White Paint
Lower quality acrylic paints are more prone to not holding its pigments together when diluted with water or a pouring medium, specially white paint.
For some reason, the chemical composition of white paint makes it break more easily than other colors. So if you are using cheap quality acrylic paints, I suggest that you at least grab a higher quality white paint. Avoid using the Apple Barrel or Craftsmart white paints. They suck!!!
I highly recommend higher quality acrylic paints such as Daler Rowney System 3, MyArtscape, Liquitex Basics, Amsterdam Standard Series, and Winsor and Newton Galeria. These paints are more pigmented so more water or medium can be added to thin the paints down without breaking the binders or reducing the color intensity.
If you are looking for a more affordable acrylic paint, then check out the Artist's Loft Academic Level paint. It is not as highly pigmented, however, the binders hold up pretty well if you don't add too much water. The Artist's Loft Flow Acrylic white paint comes in a bigger jug so it is even more affordable and doesn't crack as easily as other cheap brands like Apple Barrel and Craftsmart.
Just keep in mind that the cheaper acrylic paints usually contain a lot of binder and less pigment so your painting might not be as vibrant.
5) Be Careful With Liquid Varnishes
When it comes to varnishing your paintings, I always recommend my beginner students to stick to spray varnishes like this one from Krylon since liquid varnishes can make your perfectly smooth paint crack.
Some artists recommend to let the artwork dry completely before adding a liquid varnish on top, however, I have waited up to 30 days and my paint still crazes once I put that liquid varnish on top!!!
However, let me tell you a SECRET!!!
You CAN use a liquid varnish as long as you put a coat of spray varnish first to seal your paint.
I have to admit that I really love the glossy wet-look that the liquid varnishes give my paintings so whenever I use the Minwax Polycrylic Protective Finish or the DryLok Wetlook Sealer, I first add a few coats of spray varnish to my paintings.
Now, there are other liquid varnishes (like the Liquitex High Gloss Varnish) that don't cause your paint to crack. Not sure why! Maybe it has to do with the fact that they were specifically made to be used with acrylic paints.
It is kind of expensive, but it will give your paintings a resin like look which I LOVE! Click here to see another article I did about resin alternatives if that high-gloss look is what you are going for.
6)Paint Consistency & Layer Thickness
If your paint is too thin (most likely because you added too much water to your mix), you will have trouble with your paint sticking to your painting surface and also encounter some crazing since the binders in the paint were diluted too much.
If your paint is too thick, not only will you have issues with your paint not flowing properly across your painting surface, but you will also get some cracks due to the fact that you will most likely leave a thick layer of paint on your canvas.
So making sure that you have the correct consistency is crucial as well as not leaving too thick of a coat on your painting surface. Pour off as much paint as possible without ruining your design.
You can watch the following video to get an idea of how a paint mixture that is too thin or too thick looks like.
7)Paint and Pouring Medium Compatibility
When it comes to paint crazing, checking the paint and pouring medium compatibility is something that I have never heard any other artist mention before.
You see, I started using Artist's Loft paints with Floetrol for my acrylic pours and had never had an issue with crazing. Then I started playing with the Bloom technique which requires a different pouring medium (usually made out of a base enamel and varnish) but still kept using my Artist's Loft paints.
To my surprise, my paintings started to crack!
Initially, I thought that the issue was my pouring medium mix, so I tweaked the formula a few times with no success!!!
Then I tried my Bloom pouring medium with some Liquitex paints, and Voilá... NO MORE CRACKS!!!
Now, I don't know exactly why I didn't get cracks with the Liquitex brand paints. Maybe it has to do with the fact that the Liquitex brand is a higher quality paint and therefore the pigments hold together better.
But after all of my testing, what I do know is that not all pouring mediums are compatible with every brand of acrylic paints. Artist's Loft paints work great with a Floetrol or Glue pouring medium, but not so great with a Bloom pouring medium.
So if you are still getting paint crazing, test your acrylic paints with a different pouring medium and test your pouring medium with a different higher quality paint.
One very important thing is to take plenty of notes!!!
Write down what pouring medium you used, what brand of paint, and what the results were. This will help you pinpoint the root cause of any issues you might encounter, including cracking or crazing.
How to Fix Cracks in Acrylic Pour?
Even though crazing can be minimized through careful control of the environment and appropriate use of materials, sometimes you will unavoidably get some cracking.
At that point, you might then be wondering how to fix crazing paint.
So let's take a look at how to fix cracks in acrylic painting.
Scraping and Re-Pouring
Scraping your painting and re-pouring is an option. You can always apply a coat of gesso over your dried painting and do another pour.
But if you prefer to salvage your painting, then let's talk about some things that you can do.
First, you can't really fix the cracks in the paint, but you can disguise them or embellish them so that your painting looks more pleasing to the eye.
Here are my suggestions!!!
Fill the Cracks with Paint or Mica Powder
An easy way to fix the cracks is to fill them with some paint or mica powder.
You can use a paintbrush or your finger to dab some paint or mica powder on top of the cracks. Then wipe the excess off with a damp rag.
Here is a video that shows the process!
Another option is to embellish it. You can use markers, gold or silver leaf, beads, crushed glass, metallic paint, etc.
Glue some gold or silver leaf on top of the cracks to cover them up. You can even cover up the cracks with some crushed glass, beads, etc.
Or use some markers to draw something beautiful.
Check out the following videos to see how these people fixed their cracked paintings.
I get it!
As artists, we want our paintings to be perfect. However, keep in mind that mistakes will happen. Just make the best out of it. If you get crazing even after careful planning, then turn it into something beautiful.
If you are encountering other acrylic pour problems like no cells, lumps, muted or muddied colors, pinholes, saggy canvas, shifted image, etc, then check out this other article I made to help you get a picture perfect painting!!!
If you want to learn how to create beautiful acrylic pours step-by step, then I invite you to take a look at my Acrylic Pouring Video Course for Beginners.
You will LOVE it!!!