MotownPaul

I just had a successful cone 04 bisque fire with porcelain clay. I have cone 9/10 glaze that I will use in the next steps. Question: what benefit do I get by glazing and firing to cone 10 as opposed to just using low fire glazes and firing this porcelain bisque to cone 06? Do I get a better product at a higher temp?

I believe I need to fire to cone 10, because the clay is labeled cone 9/10 and the pre-mixed glaze I have from Spectrum is labeled 9/10. Do you know if I should be concerned about the clay sticking to the shelves during the cone 04 bisque firing with porcelain? I will be sure to have a fresh coat of kiln wash on the shelves. Do I need to take further measures?

Thanks for the quick response, Bill. My biggest concern now has to do with the pieces sticking to the shelves, especially during the glaze firing, as I understand I can’t use stilts with wire prongs at cone 10. I guess I will need to be very careful not to get the glaze too close to the bottom of the pieces. If you feel a medium or fast mode on glaze firing with all peep holes closed is OK I will go that route.

I am a hobbyist with some training in high school and college and have, so far, only worked with low-fire clays. I’ve decided to try a box (one kiln-load) of porcelain. So far I’ve thrown / built enough to fill my kiln. I’ve received conflicting instructions from my pottery supply house, glaze manufacturer and kiln manufacturer so I am coming here now to verify what I think is the correct approach to bisque fire and glaze fire. First, I plan to bisque my cone 9/10 clay to cone 04 on my Skutt electric kiln at slow speed with top peep hole open. Then I will glaze with cone 10 glaze and slow-fire to cone 10 with top peep hole open. I will not use stilts but rather keep glaze from bottom of pieces and be sure to have fresh kiln wash on the shelves. Is this the correct approach? Thanks in advance for your help.