Hi Simon, thanks for sharing your expertise on raw glazing. I have a question. I know that after you raw glaze the inside of the pot first, you spray water on the outside of the pot to equalize the expansion. My question is related to the second stage where, once it's dry again, you glaze the outside of the pot. Do you spray water on the inside (even though it's already glazed) after dipping the outside in order to counteract the expansion again? Thank you!
Any comment about single firing black clays (made with a whole lotta iron and manganese)? I have to do an extra long, super oxygenated bisque for my black clay in order to use it at the recommended glazing temp of cone 5, so I do even longer super oxygenated bisques in order to glaze fire it at cone 6 with my other clays and not have it bloat, but I have to absolutely make sure I don’t overfire. I’m concerned that the regular single fire schedules for clay will definitely not be enough to fire out all the carbon and fumes and that I would have to either change my single firing schedule to add on quite a few more hours and super oxygenate it wasting fuel and time with a bunch of clays that don’t really need that.
Im crushed. I decided to do ceramics for Christmas gifts and did some rather fine work. Then spent $30 of propane firing for 16hr and failed to make temp with my DIY kiln. Weather + disrepair was a devastating combo. Then, I destroyed the other half of my work with Mayco white crackle raku glaze *not working* . The only thing that worked was the raw glazed pieces, despite the instructions calling for bisque before glazing; which yielded a particularly crappy white gloss glaze that didn't crackle at all.
Simon YES YOU CAN FIRE ASH AT CONE 6 IN ELECTRIC!!! The Potter’s Dictionary by the Hamers states that the lower limit for ash melting is about 1100-1150C so well below cone 6. It does melt better and create more of the rivulets that we tend to want at cone 6 if you use it in a glaze with some additional fluxes. I think it is Washington Street Pottery Studio (ua-cam.com/video/LMjNeGO_wcs/v-deo.html ) that has a FANTASTIC youtube webinar on ash firing/glazing at all cones and everything you would want to know about different ashes, the differences in how you make up glazes with it at different cones-I literally learned more from that about 45 minute long webinar than I did reading both Tichane and Roger’s books- which were very informative but focuses solely on cone 10-14 ashes and they left out quite a bit of information by flatly stating their biases (to my amusement) and saying they were really mostly only going to write about what interested them, and not concentrate on everything, lol. Still highly recommended to anyone who wants to get into using ash though, most libraries have them but if you do really want to do ash glazes well worth buying, at the very least Phil Roger’s book. He has an excellent section going through all the math in such a way that even a math phobic like he said he was can totally follow the steps for taking an analysis of an ash you like but maybe don’t have the ability to get enough of, and making that into a recipe for the *ash* and then going further to sub that in for the ash content in a variety of ash glazes. Will help you know how to take an analysis off an MSDS or technical analysis from a commercial glaze and reverse engineer it into the same glaze that you can make at home for a fraction of the price as a neat side benefit.
Wood ash @ ^6, nope… glad I began not doing bisque … Sure there’s the agony of defeat when the pot cracks in my hands if not sprayed fast enough.( teaching me not to be “so precious about my pots”) Even with the destruction… There’s more victory than defeat! I use commercial brush on glazes, on occasion pouring & dipping these glazes. I have a box of chemicals… Now, must find the guts to mix it up and prepare myself for … the unknown 😂
You absolutely can use ash glazes at cone 6. You are sometimes not going to melt just 100% dry ash at that temperature but it also depends how long you fire it for and very much what kind of ash you are using. If you make a glaze out of the ash, you can have a ton of ash in the glaze and still do great at cone 6 as long as you balance other fluxes in addition to the clay or silica that you may add. Washington Street Pottery has a fantastic UA-cam lecture on ash glazes that covers everything you need to know about firing different kinds of ashes at different temperatures and more! Search for it, it is the best resource I have found on ash glazes and I’ve read Phil Rogers and Tichane’s books on it, as well as woodfiring books, but those pretty much focus entirely on cone 10-14 ash glazes. If you look in the Dictionary of Pottery Materials and Processes by the Hamers they say that the lowest limit for firing wood ashes is about 1150C, which is about cone 4, so cone 6 or what Simon is doing at cone 10 raw ash for sure can melt well.
Any way to estimate how much moisture to add to the raw piece? I just tried raw glazing a pot and that sucker cracked. I use a coarser high grog clay, would that be a factor?
So what is it that deters people from one step firing ? Is there anything in the firing process that might happen that is not desirable in one step firing ?
I don't know if Simon will answer, but at the beginning of the firing, the temperature needs to stay below the boiling point (212°F or 100°C) until all the water is gone. You check for steam escaping the kiln with a mirror or glass bottle. Then do a slow ramp up and normal glaze firing schedule. So, the hold at 200°F could be many hours. Also, glazing greenware can be tricky. Some ppl glaze leatherhard and let the piece/glaze dry together. The clay and glaze need to be a good match. Benefits are throwing/trimming on Monday, glazing on Tuesday, and firing on Wednesday. Obviously a long candle time, but still more economical than firing twice. I belong to a singlefire group on fb where firing schedules are posted, but it all comes down to candling until there's no more steam.
I once fire with brush on glaze cone 6 in electric kiln for several years now. Simon gave me the courage to try it from his videos. I preheat for 1 to 3 hours depending on when glaze was applied. But I also live in a dry climate . Never have had a problem. Cheers
@@coopart1 Same here. Dry climate combined with electric firing makes the initial candling short and easy. Chief challenge was fitting the glaze to the clay. The field glaze I use has a high clay content so the greenware has to be leather hard, not bone dry, when the glaze is applied. That way they shrink together as they finish drying.
Not only are you a master potter but you are a natural teacher. Great tips on glazing!
Hi Simon, thanks for sharing your expertise on raw glazing. I have a question. I know that after you raw glaze the inside of the pot first, you spray water on the outside of the pot to equalize the expansion. My question is related to the second stage where, once it's dry again, you glaze the outside of the pot. Do you spray water on the inside (even though it's already glazed) after dipping the outside in order to counteract the expansion again? Thank you!
Any comment about single firing black clays (made with a whole lotta iron and manganese)? I have to do an extra long, super oxygenated bisque for my black clay in order to use it at the recommended glazing temp of cone 5, so I do even longer super oxygenated bisques in order to glaze fire it at cone 6 with my other clays and not have it bloat, but I have to absolutely make sure I don’t overfire. I’m concerned that the regular single fire schedules for clay will definitely not be enough to fire out all the carbon and fumes and that I would have to either change my single firing schedule to add on quite a few more hours and super oxygenate it wasting fuel and time with a bunch of clays that don’t really need that.
Im crushed. I decided to do ceramics for Christmas gifts and did some rather fine work. Then spent $30 of propane firing for 16hr and failed to make temp with my DIY kiln. Weather + disrepair was a devastating combo. Then, I destroyed the other half of my work with Mayco white crackle raku glaze *not working* . The only thing that worked was the raw glazed pieces, despite the instructions calling for bisque before glazing; which yielded a particularly crappy white gloss glaze that didn't crackle at all.
Simon YES YOU CAN FIRE ASH AT CONE 6 IN ELECTRIC!!! The Potter’s Dictionary by the Hamers states that the lower limit for ash melting is about 1100-1150C so well below cone 6. It does melt better and create more of the rivulets that we tend to want at cone 6 if you use it in a glaze with some additional fluxes. I think it is Washington Street Pottery Studio (ua-cam.com/video/LMjNeGO_wcs/v-deo.html ) that has a FANTASTIC youtube webinar on ash firing/glazing at all cones and everything you would want to know about different ashes, the differences in how you make up glazes with it at different cones-I literally learned more from that about 45 minute long webinar than I did reading both Tichane and Roger’s books- which were very informative but focuses solely on cone 10-14 ashes and they left out quite a bit of information by flatly stating their biases (to my amusement) and saying they were really mostly only going to write about what interested them, and not concentrate on everything, lol. Still highly recommended to anyone who wants to get into using ash though, most libraries have them but if you do really want to do ash glazes well worth buying, at the very least Phil Roger’s book. He has an excellent section going through all the math in such a way that even a math phobic like he said he was can totally follow the steps for taking an analysis of an ash you like but maybe don’t have the ability to get enough of, and making that into a recipe for the *ash* and then going further to sub that in for the ash content in a variety of ash glazes. Will help you know how to take an analysis off an MSDS or technical analysis from a commercial glaze and reverse engineer it into the same glaze that you can make at home for a fraction of the price as a neat side benefit.
Wood ash @ ^6, nope… glad I began not doing bisque … Sure there’s the agony of defeat when the pot cracks in my hands if not sprayed fast enough.( teaching me not to be “so precious about my pots”) Even with the destruction… There’s more victory than defeat!
I use commercial brush on glazes, on occasion pouring & dipping these glazes. I have a box of chemicals… Now, must find the guts to mix it up and prepare myself for … the unknown 😂
You absolutely can use ash glazes at cone 6. You are sometimes not going to melt just 100% dry ash at that temperature but it also depends how long you fire it for and very much what kind of ash you are using. If you make a glaze out of the ash, you can have a ton of ash in the glaze and still do great at cone 6 as long as you balance other fluxes in addition to the clay or silica that you may add. Washington Street Pottery has a fantastic UA-cam lecture on ash glazes that covers everything you need to know about firing different kinds of ashes at different temperatures and more! Search for it, it is the best resource I have found on ash glazes and I’ve read Phil Rogers and Tichane’s books on it, as well as woodfiring books, but those pretty much focus entirely on cone 10-14 ash glazes. If you look in the Dictionary of Pottery Materials and Processes by the Hamers they say that the lowest limit for firing wood ashes is about 1150C, which is about cone 4, so cone 6 or what Simon is doing at cone 10 raw ash for sure can melt well.
Any way to estimate how much moisture to add to the raw piece? I just tried raw glazing a pot and that sucker cracked. I use a coarser high grog clay, would that be a factor?
So what is it that deters people from one step firing ? Is there anything in the firing process that might happen that is not desirable in one step firing ?
I don't know if Simon will answer, but at the beginning of the firing, the temperature needs to stay below the boiling point (212°F or 100°C) until all the water is gone. You check for steam escaping the kiln with a mirror or glass bottle. Then do a slow ramp up and normal glaze firing schedule.
So, the hold at 200°F could be many hours.
Also, glazing greenware can be tricky. Some ppl glaze leatherhard and let the piece/glaze dry together. The clay and glaze need to be a good match.
Benefits are throwing/trimming on Monday, glazing on Tuesday, and firing on Wednesday. Obviously a long candle time, but still more economical than firing twice.
I belong to a singlefire group on fb where firing schedules are posted, but it all comes down to candling until there's no more steam.
@@Lavonne9870 thanks for your reply.
I once fire with brush on glaze cone 6 in electric kiln for several years now. Simon gave me the courage to try it from his videos. I preheat for 1 to 3 hours depending on when glaze was applied. But I also live in a dry climate . Never have had a problem. Cheers
@@coopart1 Same here. Dry climate combined with electric firing makes the initial candling short and easy. Chief challenge was fitting the glaze to the clay. The field glaze I use has a high clay content so the greenware has to be leather hard, not bone dry, when the glaze is applied. That way they shrink together as they finish drying.
your first link doesnt work sir