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Nancy Talanian

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  1. Bingo! Although the glaze on the pot was thin, at least it was blue. Second photo shows the same pot bisqued to 05. So, slow cooling due to 3" bricks not only muddied the glaze but may have accentuated the 3% RIO and 6% light rutile, obliterating the 1% cobalt carb and 0.75% copper carb. To counteract this tendency in my next glaze firing, I'm planning a slow rise toward the end, shutting off the kiln when cone 6 drops. But Min's right that I should try only one change at a time. If the slow rise isn't enough, then my next move will be to cool the kiln shed with a fan and perhaps even pull one or more peeps out after 2 hours. Hmm. Maybe the reverse order. So many variables, yikes!
  2. Dick, thank you! That was exactly what I was thinking, and you've confirmed it. When I had the same kiln, I manually read the one pyrometer, and I have no written record of a temperature above 2150. The thermocouple was in the top third of the kiln. The rises may have sometimes been even slower, because although we're supposed to have 240, sometimes we had only 220 or even 215. Based on your experience, for my next glaze firing, at around 1800 or 1900F, I will slow down to 100F/hr. and just shut off the kiln when cone 6 is down throughout. Sound good? I really appreciate your input!
  3. Thank you, Mark. I will take your advice and put at least a few unadulterated cone packs in the kiln.
  4. Thank you again, Bill. I had always used light rutile, and my supply lasted for a long time. Since that batch ran out, I've tested both light and dark in 500 gm batches but unfortunately I saw no visible difference. The recipe also has a lot of RIO as well. I do appreciate your thoughts, but for now, I've decided to focus on varying the glaze firing, i.e., a slower rise, since my very old Econo-kiln with small elements wasn't capable of rising as easily as my modern one.
  5. Thank you for your insights, Bill. Although Neil called the glaze a "floating blue," it is Glossy Base 1 from Hesselberth & Roy's Mastering Cone 6 Glazes with "variegated blue" colorants. http://www.masteringglazes.com/mastering-cone-6-glazes/glaze-reformulations/chapter-6-glaze-reformulati/glossy-base-1-with-g200hp.html I still have the mug, which is as glossy as any pot I've ever seen, so the photographer must have suppressed the sheen to highlight the variegation. At the bottom and top of the mug are evidence of thin glaze. Min thought the glaze on the ugly, newer pot might be too thin, but actually the variegation shows best with thinner glaze. The change in kilns and subsequent loss of variegated appearance happened within the same bucket of glaze. Thanks also for sharing your laser technique. I've just painted a set of cone packs using different patterns (thick line, dotted, thin line) to differentiate the temperatures, and I'm firing in oxidation, not reduction, but if the underglaze markings don't suffice, I will look into your laser method.
  6. Min, you are brilliant! Thank you for the suggestion of the lines on the cones. I'm about to load a bisque, then a glaze firing within the next 7 days. Will report back afterward. I really appreciate your help.
  7. Thanks Liam and Min. Min, I really like both of your suggestions. I'll try what you've suggested in my next bisque. In the glaze firing, a 10-minute hold/soak could raise the temperature about 1/2 cone, so do you have a suggestion for the target temperature before the hold? Perhaps 2185? I could of course watch the cones like in my former, manual-kiln-watching life, but I've not had much success looking through the 3"-deep peepholes in this kiln, so getting the target close would be really helpful.
  8. Hi Min. The change in kilns came within the same batch of glaze, and I was using the same batch of (light) rutile long after that. Since then I've tried both light and dark rutile but have seen no change. You are right that the thickness of this glaze makes a difference, but not as much difference as these photos show. I didn't change the temperature to which I bisque when I changed kilns, but I have been using the Easy-Fire's fast bisque program, which takes a little longer than when I used to turn knobs on my manual kiln. Thank you, Jeff, Neal, Liam and Min for your help. This is my first time posting, and it really is wonderful not to be struggling solo in the dark!
  9. Thank you Jeff and Neil. Glazes have stayed glossy regardless of the heating and cooling ramps. Thanks for the suggestion, Jeff, but I've tried both slow cool and uncontrolled cool, and as Neil said, the 3" bricks alone have slowed the cooling from what I was able to do with the Econo-kiln. If there are any other suggestions from anyone, I'm all ears, but if not, I'll test the 120 ramp to 2199, or maybe a little slower than that, with a loose pack, and see what happens. Will report back if I get good results.
  10. Thank you again, Neil. When I made the transition I was using the same bucket of glaze. I've since mixed several glaze batches, and I've tried different suppliers for the cobalt and copper, and I've also tried both light and dark rutile, so I'm fairly certain it's the firing, not the glaze. The built-in Slow Glaze program's final ramp is 120/hr. to 2199*, so I guess I've tried it already. Since you didn't mention it, I assume you don't think my theory about slowing down even more and holding a bit is a solution.
  11. Hi Neil. Thanks for responding. Yes, both kilns are the same size, 23"; old kiln had 2.5" bricks, and new has 3". I use cone packs on every level. I've used the suggested program in Mastering Cone 6, the preprogrammed slow glaze to 6, then slow bisque to 6, and probably fast glaze too. After that I created my own programs with ramps that are a bit wacky in attempting to match what was happening in the Econo-kiln. For example, after 650, 200/hr to 1200, 350 to 1600, 225 to 1800, 150 to 1900, 200 to 2211 w. 10-minute hold. I've tested various cooling rates, but that doesn't seem to help, and in the old kiln I never did more than turn all the knobs to medium for 2-3 hrs.
  12. My rutile blue glaze (Mastering Cone 6, Glossy Base 1, Variegated Blue) hasn't been variegated since I made the switch from an ancient Econo-kiln to an Easy-Fire. Using records from old firings to program and reprogram the new kiln, I've clearly failed at matching the heat work I achieved with the old Low, Medium, and High settings on my old kiln. Glaze appears grayish and even instead of bright and variegated. I assume the difference is that my old kiln with its small elements was relying more on time than on temperature to get cone 6 down. I'd appreciate any advice for testing that theory without over-firing. I'm guessing that the second-to-last ramp before cooldown would get the kiln to somewhere between 2000F and 2150 at 100 or so per hour. Does that sound reasonable? Can anyone offer an educated guess for the final ramp (speed, target temp., and hold time, if any) to try next?
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