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View Full Version : Glaze bisque matching?



Oldmacman
29-01-2011, 01:37 AM
I like to throw cone 6 clay that is a stoneware, but sometimes I use cone 06 glazes for the vibrant colours that are available in our local shop. I went in the other day and purchased my usual clay and a mix of 6 and 06 glazes. The shopkeeper looked at me as if I had two heads and cautioned me on my purchase. I indicated that I bisque fire to 6 and then glaze fire according to the glaze number. She indicated that the durability of the 06 glaze on a 6 pot would craze over time. Does anyone have any knowledge of this? I have only being throwing for a couple months and I am still learning.

Daesul
29-01-2011, 02:16 PM
Cone 06 glazes do better on an earthenware body. I bisque fire my white earthenware to cone 04 and then glaze fire to either 05 or 06, depending on which glaze I'm using. The instructions on the glaze bottles do say that the glazes should be used on clay that has been fired to cone 04.

Oldmacman
29-01-2011, 03:45 PM
Cone 06 glazes do better on an earthenware body. I bisque fire my white earthenware to cone 04 and then glaze fire to either 05 or 06, depending on which glaze I'm using. The instructions on the glaze bottles do say that the glazes should be used on clay that has been fired to cone 04.

Thanks for the info. What are the downsides to having an 06 glaze on a 6 pot? I haven't seen any crazing yet, and just don't know what to expect over time with the finish.

Daesul
29-01-2011, 09:58 PM
I've never tried it personally. But I think the problem may be that over time the clay body and the glaze will react at different rates to room temperatures, and will cause crazing. Just a guess really.

toppotter
29-01-2011, 10:20 PM
Basically the recieved wisdom is: don't put an earthenware glaze on a stoneware body because it will craze and this may be unhygienic for tableware (however this is the desired effect in Raku). Don't put a stoneware glaze on a earthenware body as either the earthenware body will dunt/melt at stoneware temp or the glaze will shiver (peel off the body).

On the other hand I have put earthenware glazes on stoneware clay (decorative pieces only) with no visible ill effects. So as ever all i can say is test before doing a big batch and wasting alot of glaze and causing yourself a lot of heartache.

Hope this helps
Robin

Oldmacman
29-01-2011, 10:39 PM
Basically the recieved wisdom is: don't put an earthenware glaze on a stoneware body because it will craze and this may be unhygienic for tableware (however this is the desired effect in Raku). Don't put a stoneware glaze on a earthenware body as either the earthenware body will dunt/melt at stoneware temp or the glaze will shiver (peel off the body).

On the other hand I have put earthenware glazes on stoneware clay (decorative pieces only) with no visible ill effects. So as ever all i can say is test before doing a big batch and wasting alot of glaze and causing yourself a lot of heartache.

Hope this helps
Robin

Thanks for the info, it is very helpful. I have been searching online today and found an interesting article. I'll post a link after I reach 25 posts.