Baking Kato over Premo

Hi! I make purses (over molds). Interior is Premo gold and 35-40% ultra light. On a second bake I put on a thin skin ( #7 Dream machine). With the difficulty of finding clay just now, I bought Kato for the outer layer. Will curing a Kato layer on top of cured Premo and ultra light burn the the already cured layer? Elizabeth from Louisville, KY

Hi Elizabeth,

I understand your concern. The recommended curing temperature for Premo and UltraLight is 275°F/135°C and Kato’s is 300°F/150°C. It is best, of course, to stick with what the manufacturers have recommended. But as with your situation, this isn’t always possible. What to do?

Have a look at the article here that talks a bit about mixing clay brands. It gives a bit of insight and what to do in other mixed-brand scenarios.

But in your specific situation, I see no problem with baking the project at 300°F/150°C. Polymer clay does not burn at this temperature. It might turn a wee bit darker or amber colored, especially when baked for a long time. But in your project, the Premo clay is already gold colored. It’s also not on the surface. It’s well-protected on the inside of the project and therefore wouldn’t have direct exposure to the heating element.

In addition, a purse will need to be very durable. The Kato is a good choice, as it’s a very hard clay after baking. For its full durability, it should be baked as hot as your project can tolerate. In this case, I think 300°F/150°C will be fine.

Please make sure your baking setup is reliable and you’re using an oven thermometer, of course. 🙂 I also always recommend that you cover your project for additional protection from the radiant heat of the oven’s element.

Happy purse-making! 

Email is the best way
to get updates

You will LOVE getting this email, which is packed full of polymer clay goodness. About once a week.

Scroll to Top

Almost There

1

Check your email/spam

2

Click to confirm

3

Watch for welcome

Check your spam folder. Email programs are very aggressive and you’ll likely find lots of missing emails in there!

Sign Up Here

There's more by Email.

Keep in the loop about new articles and tutorials. Get tips and info. Bi-weekly emails, or thereabouts. This is the newsletter that everyone talks about.