Can anyone tell me what causes bubbles in my glaze?

Portland, OR

I am a ceramics newbie and my first glaze left lots of bubbles on some of the pieces.
I fired 25 identical (for the most part) pieces and the pieces varied from zero bubbles to one piece with a dozen or so.
Could it be that I didn't fire the bisque hot enough? Or is the temperature for the glaze all wrong. The bottle said to fire the glaze to cone 06 but all I had was 07 cones. I also fired the bisque to 07 (but I do have 03 cones for that)
Using a kiln sitter so the cones are sitter cones.
I don't have any witness cones.

P.S. This was my very first time with clay and glaze so I'm not too surprised that I am having problems.

Also, is there a more active ceramics forum out there somewhere?

Thanks

This thread has 39 replies. This forum is accessible only to subscribing members of Dave's Garden. There are many free features here, and about half of our forums are completely open to all members. Take a tour of our site and learn more about Dave's Garden, and explore the benefits of becoming a subscribing member.

Want to join? Register here. Already signed up? Click here to login!

BACK TO TOP