Working with air dry clay is a lot of fun. The possibilities of things you can make are endless, from jewellery holders to beautiful sculptures. But after putting hours of work into your creation, you’d want it to last for as long as possible. So how do you do that? Read ahead and learn how to seal your air dry clay masterpiece so that it stands the test of time.
How to Seal Air Dry Clay
You don’t always have to seal your clay. Some people prefer to make their creations and keep them just so, however, if you want your clay designs to stick around for a while then you’ll need to seal them. This is because air dry clay, unlike polymer or clay that has to be fired in a kiln, isn’t waterproof.
When unsealed air dry clay gets wet, it absorbs all of the water, making it soft. This is great news if you’re unsure about a project and you want to play around with your clay for a bit before you commit to a design, but not for those who are looking for their creations to last.
It’s also important to note that most methods of sealing air dry clay, much like the clay itself, aren’t food-safe. If you’re looking to make mugs, plates, bowls and more, then you’ll need to work with an entirely different type of clay where the sealing process includes a kiln.
Preparing Your Clay
Before you even consider what sealant to use, you’ll need to ensure that your clay is ready. When your project is fully dry, then you have the go-ahead to get started. If you attempt to put anything on wet air dry clay then the creation will lose its shape or crack as it’s drying.
Most clay pieces will take roughly 1-3 days to fully dry. If you want your drying process to be smooth and easy sailing, keep your project somewhere at room temperature and don’t touch it until it’s rock hard.
If by some small accident, the clay becomes cracked then you can create a ‘slip’. You do this by mixing a bit of clay with water. Use a brush to liberally fill in these cracks then allow that to dry and then you’re well on your way!
You can now sand the clay down to smooth over any rough patches or imperfections, then paint your creation and wait for that to dry as well, or go straight in with the sealant.
Method One: PVA Glue/Mod Podge
There are a lot of pros and cons to using mod podge to seal your creation. The first is that it’s accessible and affordable. No matter where you are in the world, PVA glue is always just around the corner. It’s also non-toxic which is great for children.
All you’ll need for this method is the glue itself and a clean paintbrush. Apply three thin layers of glue onto your clay creation. Make sure you leave one to two hours in between each coat.
This ensures that the glue dries nicely without any strange bubbles, large blobs or discolored sections. Don’t worry about the colour of the glue once you apply it either. It should dry to be clear and leave a nice glossy finish on your clay.
This is the simplest method of sealing air dry clay, but it does come with some drawbacks too. The first is that, despite the several layers of glue, it won’t make your clay waterproof. It will, however, ensure that it lasts for a long time, and it will prevent water from doing as much damage as it would have without the glue coat.
You’ll also want to make sure that your clay creation avoids direct, and constant, sunlight too. The glue might change from a clear colour to a light yellow after time.
Method Two: Resin
There are two different types of resin you can use. One requires UV light and is better for small projects like clay charms and jewelry.
The other is epoxy resin which can be toxic and requires gloves and a room with ventilation. Whichever you choose to use, make sure that you thoroughly read the instructions and are well prepared before you get started.
Once your clay project is fully dry, you can start to prep it to be sealed. It’s near impossible to paint over resin, so if you’re thinking about adding some colour to your art, it’s best to do it before the sealing process.
The first step is to glaze it with a light coat of Mod Podge/ PVA. This will prevent any bubbles from popping up during the sealing process later on and it will keep the resin from yellowing your beautiful paint.
Once your glue glaze is fully dry, you can get started with your resin sealant. Resin is one of the more favored ways to seal air dry clay because it ensures that your clay is fully waterproof. It also protects it from yellowing in the sun, making it the perfect long-term project that you can keep forever.
Method Three: Polyurethane Varnish
Polyurethane is a synthetic resin, which means that it adds a transparent non-porous layer to your clay. It also has all the pros of using epoxy resin, plus more.
Polyurethane varnish comes with three different finishes: Glossy, silky, and matte, you just have to pick one, or you could be creative and use all three on your project!
Varnish can also either be sprayed or brushed on. This is great for big projects. You can quickly spray the whole project and then use a delicate brush to get into the crevices.
Of course, with varnish, your clay will be completely waterproof and fully protected from general wear and tear and bright UV sunlight.
How Do You Seal Air Dry Clay So It Doesn’t Crack?
While working with your clay make sure that it’s wet, not too dry, and that you knead it well. The clay shouldn’t be crumbling or breaking apart as you work with it.
If it seems to be doing this, have a small pot of water at your workstation to wet your hands and keep the clay moist.
When it comes to sealing air dry clay, no matter what method you use, your clay should be fully dry. There shouldn’t be even the slightest damp spot or cracking may occur in the sealing process.
Can You Seal Air Dry Clay For Outdoors?
So long as you use a method that ensures your clay is completely water-resistant, like using a polyurethane varnish or resin, you should be able to take your clay artwork outdoors.
Do You Need To Seal Air Dry Clay Before Painting?
You absolutely don’t have to, in fact, it’s much better, and easier if you don’t. Most methods make it a lot harder to paint on your clay after sealing it.