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Everything posted by glazenerd

  1. "Get the excess clay out before you raise..." expound please.. Apparently I am missing this info.
  2. Ian Currie Test Tiles Forums?

    Joseph: those who interested will respond, those who are not -won't. We "rabbit holers" like being down here. Every once in awhile the queen of hearts speaks.
  3. Okay Prez- now for a question. the biggest problem I am having is leaving too much clay in the base. I never seem to be able to pull all the clay up the cylinder. My wall thickness is getting very close, but I would "guess-a-mate" that I am leaving a third of my clay in the base.
  4. My bullet blender, I mix glazes as I use them. I dry sieve and then mix.
  5. NCECA

    Ron: think I better give you a heads up before you go. 1. When talking with potters at NCECA; when their eyes start glazing over when talking pottery: move away slowly. You are about to hear either very detailed explanation of their last firing or favorite glaze recipe. 2. Potters with white name tags only mean they have been cooking clay for over 30 years. 3. Leave your bill fold and credit cards at home: you could easily spend more than you make. 4. The old pottery guys who have been firing for decades all have beards...right Fred? 5. Those with no sense of humor should not read this post.
  6. Ian Currie Test Tiles Forums?

    Pieter: i have noticed when firing crystalline glazes that high percentages of cobalt would make the glaze boil. Although, the 25% zinc addition has to be considered as well. However, high copper additions always retained a smooth finish. Relative??? Just an observation. I have played with SiC in cone six red recipes. It seems to favor calcium and potash in a melt. i have had better success with SiC when I chemically reduce it beforehand: which I will not discuss here. Mr. baymore made a very logical point in another thread recently about the forum audience.
  7. NCECA

    Ron: i enjoyed attending NCECA in KC back in 2016. Lots to look at and take in. I did notice a mass gathering at the bar in the evening, with lots of pottery talk. I went specifically to meet with Ron Roy, but also had the pleasure of talking with Marcia Selsor and a few others. Spent several hours talking with an old wood firer from Maine: who was every bit as obsessed with wood firing as I am with clay. I had to bug out early because of business meetings; but wish I could have gotten in another day. If you can go, do it!!!!
  8. 23167777_10155274396471374_650733566033278672_n.jpg

    Nice piece. Like the softer hue and details. Local flowers?
  9. IMG_1211.JPG

    Can spot your work a mile away...a good thing.
  10. Thrown large

    From the album Stoneware Clay Study

    Maybe, just maybe I have succeeded in throwing a large piece. Do some trimming, and attach some handles. Wait! I do not know how to make handles yet.

    © TJA 2017

  11. Detail "Emerging"

    Lee: think you are finding that " voice" that you have been looking for.
  12. Highwater clay users

    Lady: weigh out EXACTLY 100 grams of wet clay on your scale. Then allow it to dry thoroughly. Throw it in the oven at 140 if you want to speed up the process. Then weigh the bone dry clay: if it weighs less than 75-78 grams, then way too much water was added when mixed. Have my doubts this is the problem, but it will eliminate one variable. Tom
  13. Blister- carbon/sulfur

    From the album USB Images

    File image for carbon/sulfur study.

    © TJA2017

  14. USB Images

    Taken with 20x to 800S usb microscope
  15. Thrown large

    Babs: rims are what I struggle with the most. Can never seem to get them straight. Maybe another few dozen or few hundred tries- will get it.
  16. Desert night to day

    Interesting departure from your previous works. Then again there has always been an artsy flair to your thrown pieces. Interesting the level of gold nuggets in the piece.
  17. Thrown large

    1515: trimmed it down this morning: I would put the accuracy at about 90% Guess I will try handles tomorrow if I get time. Deciding rather I want to Temmoku the whole thing, or what?
  18. I will be studying/testing stoneware clay body limits shortly: next month or so. Input from stoneware users would be most appreciated. I not only need formula limits, links to recipes, or you can PM them: but also properties you find beneficial or undesirable. From the research I have done so far on c10 bodies; the general range I am seeing ( in molar) Alkali 2.5 to 2.75% Total Flux 3.6 to 4.0 Alumina 19-20 SiO2 70-75 (would assume c6 is 10% higher in flux) I did not list iron (Fe) or magnesium (MgO) ; which can vary widely pending on the clay used in formulation. Stoneware can be groged or not: what % do you find most beneficial? Light. med. or heavy. Do you think mullite grog works better than sand? How important is color? iron red, deep orange, tan to brown range...etc? Is light speckling more attractive than heavy speckling? Nerd
  19. Stoneware Limit Study

    Mea: if you look at my post before John replied.. I specifically stated: " my theory at this point is." Min, I sit corrected, I would stand but I am too tired.
  20. Stoneware Limit Study

    Mea: brick recipes and stoneware are nearly identical in molar %. My study of bloating and coring centers more on formula limits when formulating high iron clay bodies to prevent each. However, the daily relevance to potters is how to deal with these issues when they do occur. I have not drawn any conclusions yet, just looking at this point. I do however suspect the answer does not lie solely in burning out carbons. There were studies done in Germany, Switzerland, and others in the U.K. Specifically on clay bodies with nearly the same results. The more curious part of I have found was the extensive studies done on clay from 1930-1970's, and then they dropped off except those done for industrial ceramics. Which tells me when clay switched from the studio potter to mass production: the interest changed from clay to glaze.i will make a prediction however: over the next few years clay issues will out pace glaze issues. Potters will discover that many of the pin- hole, grazing, and other defects were not caused by the glaze, but rather the clay.
  21. Stoneware Clay Study

    Analyzing limits for stoneware clay
  22. Stoneware Limit Study

    Tyler: What you call being " a pain", I call passion. Passion keeps you making pots for 50 years. Passion lands your work in the Smithsonian. Passion keeps you working on perfecting a glaze, even after a year of failures. Passion keeps you throwing, even though you cannot keep it centered. Passion takes you to japan, to study under the Masters. Passion gives you the patience to spend 3 hours detailing a single cup. Problems with passion only arise when our passions are interjected into the arena that others are passionate about. I just happen to be passionate about clay chemistry: which is foreign to most. When I crossed the 60 mark I stopped measuring success in terms of achievement, and started measuring it in contentment.
  23. Stoneware Limit Study

    Once again: ammonium chloride is a white crystalline powder that is used in cough medicines, facial masks, and cosmetics. When it is heated, it produces ammonium and hydrogen chloride. The suggested amounts were along the lines of barium carbonate to prevent scumming: 1/4 to 1/2%. How that got translated into industrial levels mystifies me. I would be far more concerned about the interaction of the sulfur content interacting with other salts which produce sulfuric acid. Which by the way occurs every time you fire a high iron, high sulfur dark or red body stoneware. Your pitted and corroded stainless steel jacket is evidence of that reaction. this reminds me of the calcium borate thread I started in dec. 2015 when I arrived. There was a great alarm over my use of Imsil A-25 silica. Imsil has exposesure limits under 0.025 mg./8hr.: which is the same as any 325 mesh silica. Somehow my assertion of it being an agglomerate material was over looked. here is a recipe for standard red brick (cone 04) 50% silica , 25% Hawthorne Bond, 25% a Red Art and here is a recipe for (cone 04) red body 50% Red Art, 15% Hawthorne Bond, 25% OM4, 5% silica! and 10% talc. ( from Alfred U) Red Art, Gold Art, Hawthorne Bond, Greenstripe, Banta, Newman Red, and many ball clays were/ and are used to make brick, long before they were used in stoneware. What we call fireclay is actually brick clay. Pottery consumes less than 3% of mined clay! it is not mined for us specifically: we just adapted it for our use. Stoneware is just a modified brick recipe with different particle size distribution and slightly higher flux levels. Most brick have between 2.25 to 2.50 molar flux levels, while stoneware runs from 2.75 to 3.10. So yes, Mr. Brownell studies are most relative to our use. Or, if you prefer to look up the two studies done in Germany, another in Switzerland, a few others specifically done on clay with the same basic conclusions: be my guest. However, sounding the alarm on possible reactions is not necessarily a bad thing either. Personally, I would rate it on the order of manganese fuming. Yet, everyone has to exercise their own sense of caution.
  24. Stoneware Limit Study

    LT: Brownell proposed the use of ammonium chloride in his "Retention of sulfates by Fired Clay, 1960. The references to the link is provided above. nerd