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Bryan Johnson

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About Bryan Johnson

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  1. Are you sure that the vacuum is getting to the clay?
  2. The critique of neph sy is that it breaks down the oxide layer(reduction?) and also the aluminum (oxidation?). Years ago Ivor Lewis, on clay art said that the oxide layer is amphoteric, so I suppose it could also be oxidation . Then to counteract the problem we add epsom salts, a mild acid, which seems like should be more likely to break down an oxide layer.
  3. I think that what I am trying to figure out is why the nepheline, the component that is missing a silica would react with the oxide layer or the metallic aluminum to form pits and a hard deposit. Nepheline should react with silica to form feldspar, not with alumina.
  4. I am mostly interested in what happens with Neph Sy in clay. The explanations that I have read seem incomplete. Neph Sy is often said to have soluble sodium- where is that from and what form does it take?
  5. I am looking for some more details on aluminum pitting and the hard material that forms in proximity to the aluminum. The soluble sodium must be reacting to something, but what is formed when it dissolves? Does that play a role/or is the main contributor?
  6. https://www.jakecorboy.com/colored-porcelain?fbclid=IwAR05iEqnek_lJF0NhiWP2nyLGpL3q6BeOKMW4fVe1BiDWFqrGOJ1hiz4dLs worth looking at for color ideas.
  7. Try running a magnet through the beach sand. If you get little black particles they will work.
  8. Show us the cones. (Oops, that reminds me, I forgot cones in the bisque I just loaded)
  9. wet-wetx%shrinkage= fired or wet X shrinkage=fired or wet X(100-shinkage)=fired and fired/(100-shrinkage)=wet for 12% for 12% 1"/.88=1.13636363" .75"/.88=0.852272727" for 10% 1"/.90=1.11111111" .75/.9=0.824175824"
  10. To test for and compensate for soluble sodium with epsom salts use 1/2 of 1% of dry weight. or a few drops of saturated solution on a ball of clay that you wedging. If it works you'll notice a change in consistency. Put a couple table spoons in a jar, cover with hot water and optionally microwave 'til dissolved.
  11. Does wedging in some saturated solution of epsom salts help the recycled clay?
  12. I've been using my own mug for the last few years.
  13. Can I play too? I'd like a cone 6 translucent body with 12% shrinkage. So far NZ kaolin, silica, neph sy, and vee gum t are the whitest/most translucent, but about 18% shrinkage. Using POE, instead 0f Vee Gum T reduced shrinkage, and cost. Adding about to a fifty fifty mix of the above two a third of a body based on EPK, #6, Champion Ball Clay, neph sy, silica, and bentolite L yields a much lower shrinkage, and better feel.
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