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  2. You can't use the same percentage with every stain and expect success. Every color has the potential to behave completely differently than others. Some may be good at 5%, others at 20%. Your best bet to achieve positive, repeatable results is to weigh out both the stain and dry clay in specific amounts, testing the stain in increasing 3% increments. You can do little 100 gram tests and find the perfect percentage in one firing.
  3. I don't know if that glaze contains zinc (although they do market a zinc-free version?) I also don't know if the glaze would also mess up the color of the clay, I just know that when people have an issue with a green stain or underglaze it's usually because of zinc. There is a stain compatibility chart that Mason puts out for every color so maybe reference that chart. It has very very specific slot requirements for each color. http://www.masoncolor.com/reference-guide This says you can use with or without zinc and fires to 2300 so I'm unsure. Maybe that is the color of it? It's not a chrome green, so I am gonna guess that's the fired color or maybe you were sent the wrong stuff?
  4. Forgive me im a little confused, I only glazed one side of this, so does that mean if I used a glaze that contains zinc, even the underside(unglazed) clay body would turn this color?
  5. You'll need to use a zinc-free glaze over green underglaze (usually). Zinc turns chrome greens brown
  6. I’m lost. I used Bermuda green mason stain in my porcelain clay body and it turned dark grey. I fired to cone 6. When I mixed it I used about half pound of stain to 7 pounds of a thick slip once wedged I get about 6 pounds of clay. I mix it with a mixer and then wedge it very well. I’ve never had issues before with any other colors. I used amaco clear glaze on top. I don’t believe it’s the glaze(maybe I’m wrong) because even sections I didn’t glaze are dark grey. Someone please shed some light on this and help me achieve the right color before I lose my mind
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  8. Yep, but it would take a lot longer than if you used prepolish and polish. With my rockhounding stuff I polish smooth rocks sometimes and just skip the rough and fine abrasives.
  9. The balls in the ball mill at school were all hand rolled out of porcelain, and had a very smooth, river rock-like feel. If your items are round and roughly the same size would they be self-polishing?
  10. Thank you Neil. I actually thought of that and put an ad on Nextdoor.com to see if any one had a kiln or where I could have it done. No one answered. I know the cone - 4 to be refired. The price of replacement pieces for my pattern ( so many service pieces that are fine) dictate that it would be economically feasible to refire them. Maybe I should buy a kiln!!! I tried one patterned piece years ago. just to try. Awful, it ran and faded not usable. I will seek a place to refire one piece. (Sarasota FL) Thanks
  11. You could, in theory, refire the pieces to get the scratches to melt out, however you'd have to know the firing temp the used when making it, and it would probably change the look of the pieces. Unfortunately, dishes wear out over time.
  12. I think if you look very carefully in good light you may be able to see a difference. The porcelain won't necessarily be smoother, but it may be whiter. The problem is that if you're wrong, the earthenware will melt in the porcelain firing. The only safe way to go is to fire everything at earthenware temps. You may have problems with glaze fit, though, if you use low fire glaze on porcelain.
  13. Try applying the underglaze to bisque and then applying the clear glaze without firing on the underglaze first. It may work fine. There are enough binders in the underglaze that you should be able to brush on a clear glaze without messing it up. If it does mess up the underglaze, or you're dipping the clear glaze, then you'll want to burn out the binders before glazing. It would be nice if you didn't have to fire 3 times, though, so try applying the underglaze when your pieces are leather hard or bone dry. If you're used to working on bisque, then bone dry is probably the way to go because it will be more porous like bisque.
  14. Oh goodness don't feel stupid! Perhaps it's because you also work with earthenware and sometimes the bisque is hotter than the glaze firing with that. It's a never ending learning curve with ceramics, we've all done the occasional blunder. Yes. I agree with Roberta, try brushing some of the glaze over dry but unfired underglaze and see if it smears. (test piece) Would save a step if you can glaze over dry underglaze. Even though your supplier said your glaze will work on the porcelain I would still check with some scrap clay how the glaze fits before committing a load of your adorable creatures to it. Try different thicknesses of glaze to see how it looks over the underglazes on test pieces too. Sometimes the underglaze colour shifts when glazed, depends on the chemistry of both the underglaze and the glaze.
  15. The new belts solved the problem and cured the belt squeak with some spray belt dressing.
  16. Can you tell by feeling each piece? Porcelain has a smoother feel and is usually lighter in weight?
  17. @SweetheartSister I have used underglazes in a variety of ways. I agree with what you said about not applying the underglaze in the greenware state if your piece is small and fragile. I learned that the hard way. Perhaps I have been doing it wrong but I do not do your step #2 . I put the clear glaze on top of the underglaze ( make sure your underglaze is dry) and fire to cone 6. Done. Recently I have been doing some newsprint slip transfer work and I have been applying that to greenware pieces. Larger pieces like cups/planter/bowls, things that are not as fragile as delicate animals, jewelry or buttons (I use a lot of porcelain too!) And I have also started using underglaze on some larger pieces in the greenware state and doing some carving. Then bisque, then apply clear glaze and fire to cone 6. I like underglaze for it's ability to be used in a number of ways. I have applied underglaze for years to bisqueware. Nary a problem. But....I am trying to do more of the underglaze work on leatherhard/greenware simply because it speeds up the final glazing process. Your animals are beautiful! Wonderful detail! Roberta
  18. Hi Connie how did that work out for you?  Having a similar issue myself.  Your rheostat for your CI wheel

  19. I am fond of my good china (Lenox) and every day (Sonoma, Oatmeal) and have lots of service pieces. Over the years it has some cuts and scratches as well as the Sonoma has crazing in the glaze. Is there any remedy I can do at home? I read about cold glaze, baking in the oven. But have not found specific directions if it will work on my dishware. ?
  20. Thank you for this very detailed explanation, Min. I honestly appreciate it so much. I feel a bit stupid, firing the underglaze to vitrification temperature - I know that glazes don't take well on vitrified clay so I'm not sure why that completely went over my head. With regards to these pendants, they actually look really nice as they are without an overglaze, so for this batch I will leave them as is: 20190923_074045 by Rachel Brown, on Flickr If I wanted to repeat this process to accomodate a transparent overglaze in the future, do you think the following would work: 1. Bisque fire casts to Cone 05 2. Paint on underglaze and fire to cone 015 to burn off impurities 3. Paint on overglaze and fire to cone 7 (will mature at 6) to create final, vitrified piece. I don't think I could do liambesaw's suggestion of painting onto greenware, as the pieces are so fragile before bisque firing - it is very easy for example to chip off an ear on a pendant once dried. With regards to crazing, the supplier has recommended this exact overglaze to pair with the slip I am using from the same supplier. It is designed specifically for porcelain. So hopefully it will be okay, so long as I fire to the correct temperatures.
  21. My Last fire last week both cone 11 and cone 10 went down exactly togther in unison in same cone pack -this has happened many times-both cones show end points in same cone pack .Its not defective cones just normal wierd stuff with temps and reflected heat and downdraft flow.
  22. Bone ash, I didn't even think about that! Every so often, I have students ask, if you could get rid of a body, in the kiln. With a deadpan expression, I say "Yep"... Then walk away.
  23. I don't use cones in my regular electric firings, but I do in wood firings. My higher temp cones (9-12) bend backwards at the tip first then drop forward. Provides a nice early warning.
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