Conditioning Polymer Clay: How to Soften and Harden it.

Table of Contents

Affiliate Disclaimer: is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to also participates in affiliate programs with CJ, ShareASale, and other sites. is compensated for referring traffic and business to these companies.

Polymer Clay is an awesome clay for beginners and professionals alike but one problem, that everyone runs into, in the beginning when using polymer clay, is how to condition it. Polymer clay is not like traditional clay and therefore most of the traditional techniques for conditioning won´t work for polymer clay. But don´t worry, after reading this article, you will know exactly how to soften and harden polymer clay. Furthermore, I will show you multiple ways to do so with special tools and with everyday house items.

How to Soften Polymer Clay?

Some Polymer clay is soft right out of the package while some polymer clay can barely be moved by hand once you unpack it. So how do you soften polymer clay?

As a whole, there are several ways to Soften Polymer Clay. It can be softened by running it through a pasta machine, beating it with a mallet, kneading it with your hands, adding softer clay, or by using Sculpey clay softener.

There are a lot of different ways to Soften Polymer Clay.

The most widely known way is probably by using a pasta machine. A pasta machine is a machine that manually forces clay through a roller to flatten it. Running the stiff clay through a roller a couple of times will soften the clay up.

Good Pasta machines are quite expensive though, so I would not recommend getting one unless you plan to work a lot with polymer clay.

The next method may sound a little crude but it works surprisingly well and it is a lot of fun too. We can soften Polymer clay by hitting it with a mallet.

As I said, it may sound a little brutal to do this but this method is surprisingly effective. Simply put your polymer clay in a protective zip bag or wrap it up in some plastic foil. Then take a rubber mallet and hit the clay repeatedly until it gets soft enough to work with.

It is usually soft enough after about 1 to 2 minutes of hitting it.

The next method of getting Polymer clay soft may sound a little obvious but you have to use the right method of kneading the clay with your hand so that you don´t hurt yourself.

Don’t use your fingers to knead hard clay, this will only put a strain on your hand and muscles which will hurt eventually. Instead, lay the clay on a surface and use your hand palm to knead the clay. If you use your own weight to knead the clay then you will need a lot less strength to soften the clay.

A much easier way to soften your polymer clay is by adding soft clay or Sculpey clay softener to your stiff clay.

If you have softer polymer clay at hand, then use some of the softer clay to mix it with the stiff clay and the clay will be workable quite fast.

You could also use Sculpey Clay Softener (Amazon Link). This is a product by Sculpey, that softens clay quite fast. Only a few drops are enough and your clay will become workable. Don´t use too much of this stuff though, or your clay may become too soft!

How to Soften Sculpey Firm?

Sculpey Firm is, as the name already suggests, a lot firmer than regular Polymer Clay. This is great because you can add a lot of very fine detail to it but it is also quite hard to get this clay soft and workable.

So how to soften Sculpey Firm? In short, Sculpey Firm can be softened by running it through a pasta machine repeatedly, hitting it with a mallet, or by mixing it with mineral oils or Sculpey Clay Softener.

The methods of getting Sculpey Firm to a workable state are pretty much the same as with other clays. But Sculpey clay is actually quite a lot harder than your usual Polymer clay so you can add a lot of fine detail to it.

So you will have to run it quite a lot more through a pasta machine, than regular polymer clay and you have to beat it for longer than usual clay.

I personally would recommend using clay softener from Sculpey to make it workable.

Instead, you could also use Mineral Oil or Baby Oil.

Be very careful to not add too much though, you can easily overdo it and it will be more difficult to get it stiffer again than to make it softer.

Can I use Olive Oil to Soften Polymer Clay?

The short answer is, yes but only with caution. Olive Oil can be used to soften Polymer Clay but only if the clay is oil-based and it should be done very carefully. Only add one or two drops at a time until the clay is as soft as you want it to be.

So you can use Olive Oil to soften Polymer clay but I would be very careful when using it. Mainly because the oil will soften the clay up very fast and quite a lot.

So you don´t want to overdo it with the oil.

To use oil for softening clay use either a plastic bag or a plastic zip bag. Put the clay inside and then add one or two drops of oil to it (depending on the size of your clay piece).

Then carefully start kneading the clay until all of the oil is gone. If the clay is still not soft enough add another drop to the clay and knead it again.

Repeat these steps until the clay is soft enough to work with.

Olive oil can also be used to make the surface of your clay smoother. You can use a brush to thinly apply the oil to the surface of the clay. The oil will make the surface smooth and it will get rid of any fingerprints on the clay.

How to Stiffen Polymer Clay?

Polymer Clay can sometimes become very soft and sometimes even get sticky. This happens especially when you worked with the clay for a long time without neds or when it is quite warm, where you live. So to get it back to a workable state you will have to stiffen the clay.

To make polymer clay stiff again you can cool the clay or leave it out in the air. Soft Polymer Clay can also be mixed with stiffer clay to make it workable again. You can also place your clay between two pieces of paper and apply some pressure to it, after a few hours it will be stiff again.

As mentioned above, there are several ways to stiffen Polymer clay.

I have a complete beginner’s guide on how to work with polymer clay where I also explain how to choose the right type of polymer clay for your project. You can read it right here.

The most common reason for very soft polymer clay is heat. When your Polymer clay was exposed to a very warm environment for too long it will become very soft and sometimes even sticky (Polymer Clay can not really dry out though). If that happened to you, then simply cool your clay down again to make it stiff.

You can either put your Polymer Clay in a Fridge for a few minutes or you can also try to make the space where you work a little colder to avoid soft polymer clay.

If you kneaded your clay for a very long time, then your clay may have become very soft as well. To get your clay back to a workable state you can simply use clay of the same kind, that you didn´t work with yet, and mix it with the soft clay. This will make the clay a little harder again.

The last option is leaching your clay. This is only recommended to do if none of the other methods worked, because it may end up making your clay brittle. If you overuse this method your clay may also not harden properly after you baked it. So only use it as a last resort!

To Leach Polymer Clay simply place your clay between two sheets of regular printing paper. Then put something heavy on top of the clay and the paper to apply some pressure to it. Leave it like that for an hour or two.

After that, your clay should be stiff again.

You can also read about these methods on the official Sculpey Website, where they explain these methods as well.

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.

Leave a Comment