Why Is My Air Dry Clay Cracking? 5 Mistakes To Avoid

Seeing your ideas come to life when using air dry clay is so rewarding but when cracks start to appear you get that sinking feeling in your gut.

Did I do something wrong?

Why is my air dry clay cracking? It is normal for air dry clay to start cracking during the drying process.  Small cracks will form when the moisture in the clay starts to evaporate which will cause your clay to shrink a little, other causes include too much water used during shaping, clay rolled too thin, etc.  There are a few steps you can take to prevent cracks from appearing on your air dry clay projects.

If you see cracks appearing on your clay projects don’t be dishearted, not only is this normal but there are a few steps we can take to prevent this from happening.

I have only been using air dry clay for a few years and in the beginning, this was one of the biggest problems I faced in most of my clay projects.

With lots of trial and error and research, I have come up with a list of 5 steps you can take to prevent cracks from forming.

Check out my article on 10 Mistakes To Avoid When Using Air Dry Clay.

1. Not Conditioning Your Air Dry Clay

Before you start shaping your clay into your design.  You need to do the conditioning process for the clay you that you plan to use.

What is air dry clay ‘conditioning’?
This process is when you knead the clay for a few minutes.  This process will help soften your clay which makes it easier to work with.  By conditioning your clay before using it, will also help reduce the number of cracks forming when the clay starts to dry.

Even though using air dry clay is easy and fun, if the clay is too stiff to work with, this will result in you taking more time to shape it.

Air dry clay will start to dry once it has contact with the air in the room, so, the second you take the clay out of the storage it will start to dry.

The quicker you shape it into the design you want the better the end result will be.

This is why conditioning is so important.  It softens air dry clay.  It makes the clay much easier to shape and mold into the design you want.

You should get into the habit of conditioning your clay every time you use it, you won’t regret it.

Since I have been conditioning my air dry clay, I have found not only does the end result have fewer cracks forming but it’s so much more fun to shape and work with.

How to condition air dry clay?

• From the main block of your clay, cut off the clay that you will be using and put the rest into storage straight away.
• On a non-stick surface knead the clay for around 3 minutes.
• You will know when it is done when the clay softens up.
• Once conditioned place it into a Ziploc bag and only take out a little bit at a time to prevent the conditioned clay from drying up.

2. Not Using The Correct Thickness Of Air Dry Clay

Rolling out the air dry clay is probably the most important step each time you start a project.  Getting this step wrong can result in a lot of cracks forming when the clay dries.

As a rule of thumb roll your clay to about ¼ inch thickness.  Rolling your air dry clay too thin is one of the most common causes of cracks forming.

When you are sculpturing this isn’t the case but if you are making jewelry, plates, candle holders, etc, then the thickness of your clay is key to prevent cracks from appearing on your final project.

This mistake is more common than you think and not just for beginners.

When I first started using air dry clay, this was something I didn’t know and overlooked for a long time.  Eventually, after trial and error, I realized this was one of the causes for my projects forming cracks.

From my early research, I came across someone who wrote the thickness of your clay shouldn’t be less than ¼ inch, since I have been following this rule I have definitely noticed a huge decrease of cracks appearing on my clay projects.

Another tip to remember, let’s say you were making a square box.  Each side needs to be the same thickness otherwise it will not all dry at the same time.  This can also increase the chance of the clay forming cracks because each side is drying and shrinking at different times.

To solve this issue, you can either make sure all the sides are the same thickness or you can cover your project with a paper or plastic bag which will help your project to dry at a similar time.  Doing this will result in fewer cracks appearing on your clay project.

Tips on rolling out the correct thickness of air dry clay.

• Use a rolling pin that has adjustment thickness rings, this works a treat.  This type of rolling pin is usually used for baking but works wonders for your clay projects.  Once you set the adjustment rings to ¼ inch thickness, you will not be able to roll your clay less than that unless you adjust the rings.
• Place a pencil on each side of your clay and roll, the pencils will not let you roll any lower than the height of them.
• You can also use a ruler to measure the thickness of your clay.

This said, the more you work with your clay, the more confidence you will build and eventually you will be able to get the correct thickness just by looking and using your judgment.

However, I would still recommend purchasing a rolling pin that has adjustment rings, every project requires you to roll out your clay, and having a rolling pin with adjustment rings is a huge bonus.

3. Not Using A Non-Stick Surface

When you have finished your project and the time has come for it to be set aside to dry, you must use a non-stick surface.

Air dry clay needs room to move as it dries.  When the clay starts to dry it will also shrink a little and if the clay is restrained from shrinking because it is stuck to the surface then you will see a lot of small cracks forming on your project.  This is why you should use a non-stick surface when you set your project aside to dry.

What non-stick surface can I use to dry my clay projects?

• One of the most popular items used to solve this issue is a silicone mat.  Silicone mats have a non-stick surface which is perfect to be used with air dry clay. This will prevent your project from sticking to the surface while it hardens and letting it shrink without forming cracks.

• Another item you can use is a tile.  You can easily find single tiles at your local DIY store.  The best thing about using a tile is that you can use it again and again. If you plan to sell your projects, then it’s likely you will need to take pictures for your customers, I find a tile makes a nice surface for your projects to sit on when you take pictures of them.

• Another item you can use is a sheet of parchment paper.  It’s highly likely you already have this in your kitchen, plus it will keep you going until you purchase a silicone mat. 

What I love about this type of clay is you don’t need many tools to get started.

4. Not Storing Your Air Dry Clay Properly

This is a simple step but you will be surprised how many people get this step wrong.  When it comes to your clay, it is vital that you store it properly, otherwise it will dry out.

When it comes to storing your air dry clay you have a few options.  The following are the most popular methods for storing clay:

• Wrap your clay with saran wrap.
• Place it into a Ziploc bag or an airtight storage container
• Store it at room temperature.

Whichever option you choose to go with, you should always store your clay at room temperature.   I find the best place to store your clay would be a closet of some sort.

If your clay is not stored properly then it is likely to dry out and get crumbly.  If this happens your clay will become hard to work with and it will form more cracks after you let your clay projects harden.

5. Weak Joints

After using air dry clay for a bit, you will notice that you will start to try more complex projects, and this usually involves joining 2 or more separate pieces of clay together.

Weak joints between separate pieces of clay will most likely cause cracks to appear on your clay projects.  So when you join multiple pieces of clay together always make sure that the joint is strong.  Scoring your clay before joining it will make a huge difference when it comes to cracks appearing on your projects. Using a lightly damp sponge or paintbrush will also help with making the joint stronger.

A lot of people new to air dry clay struggle with this in the beginning, I know for a fact that I did. 

After a bit of practice, joining multiples pieces of clay together will become second nature.

Air dry clay tools normally come in a set and you always find the scoring tool is one of them.  You can purchase a set for around $15 which is great value, but if you don’t have the funds in the beginning you can always use a wooden toothpick to score your clay, to give you a strong joint.

Final Thoughts

Some air dry clay projects take a long time to complete and a lot of hard work, so the last thing you want happening is for cracks to appear on your projects.

There are many reasons for using air dry clay and cracks appearing is part of the learning process.

In this article, we looked at the 5 most common causes for cracks to appear on your clay and what you can do to prevent them.  These included:

• Not Conditioning Your Air Dry Clay
• Not Using The Correct Thickness Of Air Dry Clay
• Not Using A Non-Stick Surface
• Not Storing Your Air Dry Clay Properly
• Weak Joints

I hope you have found this article helpful and have a better understanding of why cracks could be appearing on your air dry clay projects and what you can do to prevent them from appearing.

If you have any other tricks to prevent cracks from appearing on your clay projects then please share them down in the comments.

Let’s share and learn together.

Happy Crafting!