Do you have a kiln & do ceramics?

monica2001November 18, 2002

Hi, I have a small kiln and have only had it about two years. I need advice from someone who has had a hobby ceramics kiln for years. Is anyone out there that I can ask questions? My first question: At the Senior Center I used to attend in TN, we would fire a small amount of greenware mixed in with the glaze. The firing cone would be for glaze. The greenware would not be anything that food would be kept in. I was recently told that "that cannot be done - it will explode!" What do you think? Monica in TX

Thank you for reporting this comment. Undo

Hi Monica! depends on the glazes and the clay bodies you are using. If you are using low fire glazes, like a cone 4-6 I don't see why it would be a problem to do greenware at the same time since there are plenty that fire cone 4-6. Just make sure your greenware & glazes are compatible.
I have not mixed items in a kiln myself, so there may be some other reason I'm unaware of.


    Bookmark   November 19, 2002 at 9:05AM
Thank you for reporting this comment. Undo

If I was mixing I'd probably load the glazed pieces first, then greenware on top. That way if there was any fumes or moisture from the greenware it would rise and not effect the glaze.


    Bookmark   November 19, 2002 at 9:11AM
Thank you for reporting this comment. Undo

Thanks Karen for your remarks. What surprised me was when I was told it might explode! I could understand that greenware should be fired to a higher cone to be used for food. I understand that the fumes could affect color, but explode? I once fired gold accidently on a non-overglaze compatible glaze. It sure looked funny, but never exploded. It is my understanding that if something is poured wrong and has an air bubble inside it will explode, but never glaze and greenware. By the way, your idea of having the glaze on the bottom because of fumes is excellent. My kiln is so small (11 x 14") that loading is a challenge. Thanks, MonicaTX

    Bookmark   November 19, 2002 at 2:47PM
Thank you for reporting this comment. Undo

I always thought exploding was due to excess miosture in the clay. That an excessively high temp for the greenware could "solidify" the outside too soon while trapping moisture inside the piece- especially if it is thick. Heat would cause the moisture to turn to steam and the force would "explode" the piece. I have had this happen with some pieces my students did in art class. It can break other pieces in the kiln, too.
Your kiln is petite!...sounds like a jewelry kiln size. I'd like to get one that size for silver Artclay and glass fusing.


    Bookmark   November 19, 2002 at 8:05PM
Thank you for reporting this comment. Undo

What they mean is that if the greenware has air bubbles or moisture in it, it can explode. If a piece of greenware does explode, sometimes pieces of it can stick to the glazed pieces. Also, sometimes the fumes from the greenware can effect the color of the glazes, especially reds and oranges.

Cones 4-6 are high fire. Cones 06-04 etc., are low fire. Probably just an oversite.


    Bookmark   November 20, 2002 at 7:10PM
Thank you for reporting this comment. Undo

Thanks Cindy!...I should have had the 0's.

    Bookmark   November 21, 2002 at 11:42AM
Thank you for reporting this comment. Undo

Another reason not to mix greenware and glazed items is that a glost firing can be stepped up much faster than a bisque firing. When firing such a mixed batch, the needs of the greenware will have to be the prime concern as there are many important changes taking place.
Also, as others have said, be VERY sure that there is no residual moisture in the greenware (and I am using the word greenware in the sense of "raw unfired clay").

    Bookmark   November 23, 2002 at 1:00AM
Sign Up to comment
More Discussions
repairing crack in Terra Cotta pot
Hi, We have a large terra cotta pot that we (foolishly)...
Does anyone make memory beads with oven clay?
I am wanting to learn how to make memory beads by incorporating...
Ceramic Wall
What is the best way to clean Ceramic Wall tiles?
Bisque BArrel Firing
Is it possible to bisque fire in a barrel? I tried...
Slip casting smoker/ grill
Hello all Please forgive me I am a metal guy. Also...
Sponsored Products
Pogo Satin Nickel LED Mini Pendant with Dome Canopy and Silver and Inner Silver
$432.00 | Bellacor
Cutlery Tray
CliqStudios Cabinets
Herman Miller | AeronĀ® Posturefit Polished Aluminum - Quick Ship
International Caravan Set of Three 'Madrid' Resin Wicker Outdoor Bistro Group
Hammock: Tropical Palm Stripe Soft Comfort Hanging Hammock Chair
$83.99 | Hayneedle
Oxford Armchair - Adjustable Height by Fritz Hansen
$2,414.00 | Lumens
© 2015 Houzz Inc. Houzz® The new way to design your home™