Top Secret Tips for Working with Polymer Clay

I’ve got a few polymer clay tutorials coming soon, and thought it’d be a great idea to round up my top tips and tricks in one place. So here we go!

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First, let’s talk about BRAND. Not all brands of polymer clay are equal!

You’ll see that I’m mainly using Sculpey Premo in my videos. Why? Because I did quite a bit of research about the various clays out there, and the experts tend to agree that Premo is both easy to work with and strong after baking.

Some clays, like Sculpey III, to name one, have a reputation for being a bit brittle after baking. (Which seems kinda silly since Premo is made by Sculpey!)

Anyway, the three clays most people seemed to recommend were Premo, Fimo Professional, and Fimo Soft. I went with Premo mostly because the big blocks of the white clay that I wanted were cheaper than the big blocks of Fimo Professional at the time I was buying them.

Now, let’s talk about TOOLS.

They sell variety packs of clay tools, but the truth is, you really don’t need anything fancy.

A toothpick, a drinking straw, an old butter knife. Use what you’ve got! However, if you use any kitchen implements with your clay, like a butter knife, please make it a designated clay tool and don’t continue using it to eat with!

There is one very important thing to consider when choosing tools and a workspace, and that is… porosity. You need to be careful when using porous materials like paper, cardboard, and wood when working with clay. Because porous materials will soak up the chemicals in the raw clay.

This is bad for a variety of reasons. One, it can make the clay crumbly, because you’re literally changing the chemical composition by removing some of that content from the clay. Two, those chemicals are going to get into the porous material and you won’t be able to get them out.

I use a silicone mat to protect my wood table and a piece of wax paper to protect my wooden rolling pin.

I mentioned using a toothpick as a tool, and that’s not a big deal since it won’t come into prolonged contact with the clay. But using a wooden rolling pin or working on a butcher block? Not a good choice. If you absolutely need to use wood for some reason, put a layer of plastic wrap or wax paper between it and the clay.

But aside from that, anything can be a great tool! Aluminun foil is a great way to add texture. So is an old toothbrush. Get wacky!

Here’s a tip you probably wouldn’t think much about… STORAGE.

Remember the chemicals in the clay we talked about earlier? Those same chemicals can react with some types of plastics over time, softening and sometimes even melting them. It won’t happen immediately, but pay attention to what you’re storing your clay in or on when it’s in its raw state. Once it’s baked, you don’t have to worry about this.

Plastic wrap is safe, so I like to wrap my clay in that and then I don’t have to worry about what type of container it’s being stored in after that.

Then I usually use a mason jar because its nice and air tight.

Now let’s address clay conditioning.

Right out of the package, clay can be kind of crumbly and not smooth. That’s pretty normal. It’s almost the consistency of cheddar cheese.

The first step to any clay project is to condition the clay, which really means to smush it around until it’s nice and pliable and smooth. The pros use a pasta machine for this, which is admittedly easier than doing it by hand.

But there is another way to make conditioning by hand easier, especially if you’re conditioning a large amount of clay. Get something warm — I like to use a microwaveable rice bag, but you could use a heating pad or a hot water bottle (something warm but not hot) — and set it on your chunk of clay for a few minutes. It should be much easier to work with once it’s a little bit warm.

Also, when rolling out clay into a slab… I mentioned using wax paper earlier to protect wooden implements, but I also like to use wax paper to keep the clay from sticking to my metal rolling pin which can be very annoying!

Now let’s talk armatures!

Clay isn’t the cheapest thing in the world. So sometimes instead of making one solid chonk of clay like this, it might be more efficient to make an armature — foil and wire work well — and then cover that with clay instead.

Solid clay ball

Here I’ve made a ball of aluminum foil and wrapped that with a thin layer of clay. This requires way less clay and will also need to bake less (baking time is based on clay thickness).

See? You can’t even tell the difference once they’re shaped.

Solid clay ball vs. clay-wrapped foil ball.

Generally, I try to limit clay thickness to about 3/8″. If I’m making anything thicker than that, I’ll usually use some sort of armature.

Connecting two pieces of clay can be tricky, too. Making a snowman might seem easy — just roll two balls and stick them together — but those two pieces of clay don’t really want to stick together. Even if you smush them together really well (which deforms the shapes, by the way), it doesn’t make a very strong bond.

Two pieces of clay pressed together like this will very often come apart after baking.

Wire to the rescue! This is just some plain old 20 gauge wire. (Anything from about 14-26 gauge should work for these purposes.) I’ll snip two pieces about 1/4″ long and embed them where the two pieces of clay connect. Push them into the first piece about half way. And then attach the top piece and boom! No more roly poly balls.

Now if you really want to strengthen that bond, add a dab of liquid clay between the pieces in addition to the wires. The liquid clay will act like glue once this is baked and you’ll have a really good bond!

You can also glue two pieces together after baking, which you might do intentionally or you might do as a repair. A flexible superglue like Loctite Gel works best for gluing two pieces of baked clay together.

One of the most important tips I have is for when it comes time to bake.

This is probably where most people go wrong with polymer clay. Polymer clay is cooked at a somewhat unusually low temperature, though it varies depending on your clay.

Premo, for example is 275 F. Fimo is 230 F. You’re probably used to baking and roasting at more like 375. It’s really important to bake at the correct temperature for your brand of clay. Higher temps WILL burn your clay.

The first time I ever tried to bake polymer clay by myself as a kid, I set the oven temperature wrong. I’d made all of these cool rainbow swirls, but every single one of them burned, and I ended up with a whole cookie sheet of what looked like poop swirls. Boo.

So again, read the temperature on the label for your clay and follow it.

As for time, this where things get interesting. Baking LONGER than the package says actually yields a stronger final product. And this isn’t such a bad thing since it can be hard to determine the correct time. The time is often given in increments like “thirty minutes per quarter inch.” And you might not have a perfectly uniform piece you’re baking.

So it makes sense to bake for extra time. I try to figure the absolute thickest point of my project and then add 15-30 minutes to that. I always err on the side of overbaking versus underbaking.

I made a whole batch of these button pattern weights, but I underbaked them. They looked great for the first few weeks, and then every single one started to crack. And when I peeled some of the clay off, I found the clay underneath was still kind of pliable. I will never underbake again!

Another tip for evenly baking your polymer clay is to get a large ceramic tile to bake on top of. This is an absolutely optional step, and I bake clay all the time without it, but if you’re looking for a way to improve our clay baking game, it’s something to consider.

Next, if you’ve ever baked on a piece of aluminum foil and noticed the back of your clay came out with weird shiny spots, that’s because the bottom if the piece will take on whatever texture is underneath it.

I don’t particular like the shininess from foil, and I’m usually baking on these old crusty pans, so how do I get a nice matte texture? Bake on a piece of paper.

So now you’re probably saying, I thought you said we shouldn’t put the clay in contact with porous material like paper!

And that’s true. If you have parchment paper on hand, use that. The coating on the paper will prevent leaching. But if not, you can use a regular old piece of printer paper. Just don’t put the clay on the paper until it’s ready to go into the oven. As long as the raw clay isn’t sitting on the paper for hours and hours, it’ll be fine.

Another baking tip is to cover your project with an aluminum tin while baking. Polymer clay tends to be a touch stinky when it bakes. It’s not the worst smell in the world, but it doesn’t smell great either.

Covering while baking seems to almost totally eliminate any odor, which is a bonus. Covering the clay while baking will also prevent potential discoloration if you have any uneven heating going on inside your oven.

Once you bake and cool your clay, it’s time to finish!

You can paint. Acrylic paints are a great choice. Or you can dust with mica powders. Add a crackle finish. Decoupage. Glitter! Or you can leave it as is.

So then the question becomes: to seal or not to seal?

If you haven’t painted or added any kind of finish, you do not have to seal your clay project. However, most paints and finishes need to be sealed, or they will scratch or wear off over time.

Sealers are another thing I did a whole boatloat of research on. I was all prepared to use my can of spray gloss I had on hand on my creations, but apparently there are very few spray topcoats that work on polymer clay. In fact, a LOT of clear sealers — even the ones you brush on — appear to work at first, but within a few weeks, they will get tacky and sticky once they start reacting with the clay. Not good for business!

So please don’t go slopping whatever glossy top coat you have on hand onto your creations without doing some internet research as to how it interacts with your particular brand of polymer clay.

There is one sealer that has a reputation for working on pretty much all polymer clay brands. It’s called Varathane water based polyurethane. So that is what I use and recommend. The cool thing is, it comes it small cans, and they have all the various finishes you might want: gloss, semi-gloss, satin, and matte!

Polymer clay pattern weights painted with acrylic paints, crackle finish, and finished with Varathane gloss polyurethane

My very last tip is to check out This is like the holy grail of polymer clay research! If you have a question about polymer clay, she’s probably answered it, in great detail, with tests and photos and the whole enchilada! So when in doubt, check thebluebottletree.

If you have a tip of your own, leave it in the comments below.

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