Air dry clay is probably the favorite type of clay of most hobby crafters because it is easy to use and it doesn´t require a kiln to cure instead it dries after a while. But how long does it take for air dry clay to properly dry?
As a whole, air dry clay usually takes between 24 and 72 hours to dry depending on the brand of the air dry clay, the humidity level in the room, the temperature, and the thickness of the clay. A higher surrounding temperature will speed up the drying process while a higher humidity level will slow it down.
Air dry clay is notorious for cracking when it dries too fast or unevenly so it is always best to let air dry clay dry slowly and far away from any heat source.
You can always check if the air dry clay is dry by pressing your nail in the clay in a location that won´t be visible later like the underside of your sculpture for example.
If the air dry clay gives in easily then it will probably take another day to be fully dry. If the clay gives in just a little bit then the clay is about halfway dry.
And if the clay is dry then it won´t give in at all.
What Factors Can Influence the Drying Time of Air Dry Clay
There are several factors that can influence the drying time of air dry clay. You should generally let air dry clay dry as slowly as possible to keep any cracks from forming.
Temperature
Temperature is the most important part when drying air dry clay.
You don´t want the temperature to be too high or the clay might crack or even break but you don´t want it to be too cold either or the clay will take forever to dry.
Air dry clay should be dried at room temperature and the clay should be kept away from any heat source like heaters for example.
But you should also keep the air dry clay away from the window or the fridge while it is drying because cold air can lead to the clay drying unevenly which will result in cracks forming.
Humidity
If you live in a very humid country then you will have a hard time getting your clay to dry properly.
Air dry clay cures when water evaporates from the clay. But if the humidity in the room is too high then the air will only slowly accept more water so the clay will dry very slowly.
The best thing that can be done when you are struggling to get your air dry clay to dry is to introduce some airflow to the room.
Try to keep the clay out of the direct path of the airflow or the clay will dry unevenly and cracks will form.
My recommendation would be to open the windows and keep the clay sculpture in a corner of the room. It will probably take around three to four days for the clay to dry in a humid environment.
Airflow
I already mentioned airflow before but it is very important so I will describe why airflow is so important in this separate section.
You should never have your clay sculpture dry near an open window or near the air conditioning or the clay will form cracks.
If there is too little airflow in too small of a room then the clay will dry very slowly. Don´t let the clay dry in a small room or inside a drawer or something similar.
Instead, put the clay in a big room and cover it with a loose piece of plastic. This will make it so that the clay dries evenly and is protected from any air hitting it directly.
Type of Clay
Finally, the type of clay will also influence the drying time of the clay. There are many brands and types of air dry clay and each has a slightly different drying time.
You can usually refer to the packaging where it usually tells you how long it takes for this specific clay to dry.
But most air dry clay will dry within 24 to 72 hours under normal conditions.
How to Speed Up the Drying Process of Air Dry Clay
For some people, 72 or even 24 hours might be too long to wait for air dry clay to dry. So is there a way to speed up the drying process of air dry clay?
Yes, the drying time of air dry clay can be sped up by carefully warming the wet clay evenly by either putting it in the oven at a very low temperature (25°C / 77°F or 30°C / 86°F). Some ovens even have a drying setting. A hairdryer can also be used but it has to be moved constantly and cracks will probably form.
I really don´t recommend speeding up the drying process of air dry clay in any way because it will almost always lead to cracks forming in the clay.
But if you are in a hurry then using an oven to speed up the drying time is probably the safest way as it will distribute the heat evenly. Use a very low temperature to ensure that the clay forms as few cracks as possible.
And if cracks form then don´t worry. You can fix most cracks rather easily.
What to Do When Cracks are Forming
If any cracks form when drying air dry clay then they can easily be fixed by using something called slip.
Slip is a mixture of water and air dry clay that can be applied to a crack effectively fixing the it.
When mixing slip I usually start by mixing the clay and the water in a 50/50 ratio. But I sometimes have to add a bit more water to get the right consistency.
The consistency should be that of yogurt.
How to Properly Dry Air Dry Clay Slowly and Controlled
Finally, here is the recommended way of drying air dry clay. If you follow this advice then you will easily dry your clay without many, if any, cracks forming.
1. Cover Thin Parts with a Damp Paper Towel
First, if some parts of your sculpture are thinner than others then you need to make sure that these parts don´t dry quicker than the rest of the sculpture.
To do this we need to cover thinner parts with a damp towel. Don´t make the towel too wet it’s just supposed to be damp.
2. Cover the Whole Sculpture With a Piece of Plastic
Next, cover the whole sculpture with a thin piece of plastic. Don´t wrap the plastic around the sculpture, instead place it loosely on top of the sculpture.
This will keep the whole sculpture from drying out too fast and thus keep the sculpture from cracking.
3. Place the Sculpture in a Corner of the Room Away From Any Heat Source
Finally, place the sculpture in a corner of the room away from any heat source or direct airflow and let the sculpture dry for at least 24 hours.
It is best to place the sculpture on a grill plate or something similar. This will ensure that air can reach every corner of the sculpture ensuring that it dries evenly.
Remove the damp towel after around 10 to 12 hours but don´t remove the piece of plastic.
It is best to leave the air dry clay to rest for longer than the recommended drying time to make sure that it dries properly and safely.
4. Sand the Sculpture if Needed
After the sculpture is dry you can sand the surface to make it smoother.
This isn´t necessary but it is helpful if you want a smooth and even finish on your sculpture.
Hi, I am a passionate maker and professional prop maker for the entertainment industry. I use my woodworking, programming, electronics, and illustration know-how to create interactive props and puzzles for Escape Games and marketing agencies. And I share my knowledge and my experience on this blog with you so that you can become a maker yourself.