{"id":24380,"date":"2025-01-04T13:15:00","date_gmt":"2025-01-04T13:15:00","guid":{"rendered":"https:\/\/cursist-courses.com\/bisque-firing-in-ceramics-what-is-it\/"},"modified":"2025-02-06T15:00:02","modified_gmt":"2025-02-06T15:00:02","slug":"bisque-firing-in-ceramics-what-is-it","status":"publish","type":"post","link":"https:\/\/cursist-courses.com\/en\/bisque-firing-in-ceramics-what-is-it\/","title":{"rendered":"‘Bisque firing’ in ceramics, what is it?"},"content":{"rendered":"\t\t
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The first firing step is the so-called bisque fire: your piece has already been fired in the kiln once, but it is still porous and in most cases not quite finished. What are actually the differences between a bisque fired piece, and a piece that hasn’t been fired yet? And what exactly happens during the bisque firing? <\/p>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t

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Properties of bisque fired pieces<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t
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You can still dissolve an unfired piece in water, no matter how dry it is. The clay in a biscuit-fired piece, on the other hand, has become too hard for that. It has undergone a chemical transformation during firing: it has become ceramics. <\/p>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t

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A biscuit-fired piece is permanent, but it is not yet waterproof in most cases. (Exception: porcelain is already waterproof after the bisque firing). <\/p>\n

This is not a problem if you are making a planter, for example, but for sorts of work it is not ideal. So time for a coat of glaze. <\/p>\n

After the bisque fire, your piece is in an ideal state to be glazed. This is because it will absorb the water from the liquid glaze, causing the glaze powder to stick to the clay. <\/p>\n

Your work is then ready for a second round in the kiln, which will ensure that your work is waterproof.<\/p>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t

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What happens during the bisque fire?<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t
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Your piece undergoes several stages in the kiln.<\/p>\n

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  1. As the kiln heats up, excess moisture evaporates from the clay.<\/li>\n
  2. From a certain temperature, organic material (if present) in the clay begins to fire away. In addition, water chemically bound to the clay particles also begins to disappear. <\/li>\n
  3. At higher temperatures, the chemical and mineral components in the clay also fire away. The heat causes your piece to expand slightly. <\/li>\n
  4. The surfaces of the clay particles are chemically activated and bind together, shrinking your piece. This phase is called ‘sintering’. <\/li>\n
  5. Finally, ‘vitrification’ occurs. Chemical components in the clay melt and form a liquid glass, to which the clay particles bind. If all the spaces between the clay particles are filled with glass, the end result is waterproof. But with a bisque fire, this is usually not the case: the glass formation is only halfway through and the end result is therefore still porous. <\/li>\n<\/ol>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t
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    \n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\"bisque\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t
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    Want to know more about the clay stages?<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t
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    Download your free overview here.<\/p>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t

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