Clay Frequently Asked Questions
This is a compilation of questions about polymer clay that I've seen asked in polymer clay forums. Do you have a question that's not addressed here? Ask me at hello@polyclayemporium.com!!
Do I have to keep my raw polymer clay in air-tight containers?
No, polymer clay doesn't dry out in the air. You can store any way that is convenient. There are a few types of plastic that don't behave well with polymer clay Avoid these, and your clay collection will be safe and happy ꩜ .ᐟ
What is the difference between polymer clay and air dry clay?
So, picture this: you've got these two clays, right? They're like polar opposites in how they get from squishy to solid.
Take air dry clay, for instance. It's like magic! Just leave it out in the open air for a day or two, and boom! Hardened! No fancy equipment needed.
Now, let's talk about polymer clay. This stuff marches to the beat of its own drum. It stays all soft and moldable in the air, teasing you with possibilities. But here's the twist—it only decides to get serious and harden up when you pop it in the oven. Just follow the brand's instructions for time and temperature, and voila! You've got yourself a masterpiece in the making.
Does polymer clay shrink when baked?
Google this question, and you'll find crafters who say that it definitely does. And other who state, just as definitely, that it doesn't. Clay Guru Phyllis Cahill provides us with actual data. She performed the experiment with different clay brands. She cut 5" strips of clay, baked them, and remeasured them. She tested 5 different brands: Cernit, Fimo, Kato, Premo and Souffle. Her findings? Premo and Kato shrank about 1/16", Fimo, 1/32", and Cernit and Souffle, not at all. So now we know! Thank you, Phyllis! You can read her original study here.
Can I cure polymer clay by boiling it?
Nope, it's all about the heat!
Polymer clay is made from tiny PVC particles (like those in plastic pipes) mixed with plasticizer to make it moldable. When curing, you heat the clay so the plasticizer softens, letting the particles move easily. As the temperature rises, the particles polymerize, forming long chains that solidify the clay.
Recommended Baking Temperatures:
- Sculpey: 275°F
- Fimo: 230°F
- Pardo: 266°F
- Kato: 300°F
- Cernit: 265-275°F
Water boils at 212°F at sea level, and even lower at higher altitudes.
See the issue? Boiling water just can't get hot enough to soften the plasticizer and trigger polymerization. So, your polymer clay won't cure properly.
My earlobes get itchy and red with almost all earrings. Will polymer clay earrings be OK for me?
Part 1 of answer: The polymer clay. Your skin is unlikely to react to contact with polymer clay. Even if the earring has a resin coating, your skin will probably be fine. The medical literature has scattered case reports of contact resin allergies, but these have occurred primarily in ship-yard workers who are frequently around large amount of polymer.
Part 2 of answer: The findings used on the earrings are usually metal. Whether you'll be OK wearing them depends on which metals your body has become sensitized to. 'Hypoallergenic' has become meaningless at telling you what metals are in the findings. Some earring-wearers look for the phrase 'surgical stainless steel'- but there is in fact no formal definition of surgical steel, which can contain chromium, nickel, and molybdenum.
You might be find with sterling silver- which contains 92.5% silver and 7.5% other metals, usually copper. This is added because Fine Silver (99.9% pure silver) is too soft for most jewelry purposes.
Argentium silver is more recently developed. It is a tarnish-resistant alloy with 93.5 to 96% silver, usually combined with copper and germanium. Niobium is an entirely different metal (41 on the Periodic Table of Elements) so skin reactions to this are very uncommon.
A final option is plastic findings. The ones I've seen so far are neither attractive nor durable- but some inventor/designer may be cooking up a great plastic and design as you read this.
Bottom line, Part 2: You've got to be your own Sherlock in figuring out what metals bother your earlobes- and then avoid them!