Hard and crumbly polymer clay could be older, partially cured, or the plasticizer has evaporated or leached out. Some clays tend to be more crumbly by nature if older than a year or so old, e.g., Cernit Doll clay. The question is, can it be successfully , softened, conditioned and then used?
Bottom Line or Pro — Unless the clay had been cured, most hard, crumbly clay can be softened.
Pro: Not all methods of softening difficult-to-condition polymer clay require adding products (see Methods 1 through 3, below).
Possible Con: Adding products changes the way clay feels and behaves so some techniques will require new, fresh clay instead. If in doubt, test.
Work it or Buy Fresh Clay? That’s a decision that you’ll make based on a variety of criteria. Personally, with the price of larger “bricks” of different doll clays, which is mostly what I have, I’m going to choose “work it” more often than not. I’ve worked really old clay (10 to 15 years old) for 30 to 40 minutes, conditioned it, and used it with satisfactory to excellent results. Often, it doesn’t take nearly that much effort. If it literally hurts, you might want to consider using a mallet or NeverKnead (a machine).
Goal: The Goal of Methods 1, 2, and 3 are to make it possible to clump your clay together and run through the pasta machine repeatedly and/or work it with your hands in order to condition your polymer clay.
Method 1: Put it (in a zip lock baggie) in your pocket, otherwise against your skin, or in a microwave pillow for a bit to warm it up.
Now try to condition it.
Method 2: It’s not too stiff and crumbly but still needs a little more help?
Soften it with a combination of conditioning and adding new materials to make it supple and workable. Here are your options. Some of you will want to try the physical methods first, especially caners.
- Whack It — Whack the clay with a rubber mallet to “get things moving.” A few good whacks can “jumpstart” conditioning — the more you whack it, the better it behaves, generally.
- NeverKnead (Tool)– NeverKnead is a modified arbor press that smashes polymer clay. It allows you to condition it without hurting your hands, and while it’s not a substitute for a pasta machine, it lessens hand fatigue. This can be a boon to those with arthritis and so on.
- Use Clay Softener (Diluent) or Translucent Clay – Work some softener or translucent clay into it.
- Translucent clays – Translucent are often a bit softer than opaque clays.
- Fimo MixQuick — Fimo MixQuick helps soften hard polymer clay.
- Sculpey Mold Maker – Sculpey Mold Maker can also help soften hard polymer clay.
Now try to condition it.
Method 3: If it’s really hard, crumbly, and unresponsive
- Chop — Chop up the clay in tiny bit using a blade or dedicated food processor.
- Add — Add Sculpey Clay Softener, mineral/baby oil, liquid polymer clay, or Fimo MixQuick to your polymer clay, if you didn’t already, or maybe again if it needs it, and mix.
- “Simmer” in a Ziplock Bag — Place in a zip lock sandwich bag let sit for a few days in a cool, dry, dark place so that the liquid or plasticizers in Fimo MixQuick seep into the hard clay and soften your clay.
- Repeat — Repeat the process with more liquid or Fimo MixQuick if necessary.
- NeverKnead/Mallet — Whack the clay with a rubber mallet to “get things moving” and/or use the NeverKnead.
Now Try to condition it. Again, the goal of the above 3 methods is to make it possible to clump your clay together and then condition it in the pasta machine and/or with your hands.
If even method 3 doesn’t work, your clay was probably cured. It can be used as clay crumbles in faux rock or other uses, perhaps, or it can be thrown out.
Avoid ordering your clays in the hotter summer months, buy clay only just before you need it, and/or consider your storage conditions. Your clay is supposed to be stored in a cool, dry, dark place. Many people try to order the clay just before use. Others found a bargain and store it until later.
I have clays that are 10 years and older that I’ve conditioned and used. We have central air. I store my clays out of the sunlight in a cool, dry, dark place.
Polymer clay can start partially curing at 90 degrees F. So while it’s okay to warm polymer clay against your body before conditioning for short periods of time, never leave your polymer clay in a hot car while shopping or on a warm windowsill. Store it in a cool, dry, dark place…about 74 degrees or lower, ideally. If you don’t have a house or other storage in which you can keep it 74 degrees or lower, your clay may not fare well if stored for longer periods of time.