Darvan/dispersant & slip ..is that the need 4 non-Newtonian thixotropic character reversel in wheelwork. - Electric Mid&Hi Fired Ceramics2024-03-29T10:25:10Zhttps://cone6pots.ning.com/forum/topics/darvan-dispersant-slip-is-that-the-need-4-non-newtonian?xg_source=activity&feed=yes&xn_auth=noDarvan traps calcium and magn…tag:cone6pots.ning.com,2019-08-14:2103784:Comment:1543442019-08-14T04:55:04.968ZNorm Stuarthttps://cone6pots.ning.com/profile/NormStuart
<p>Darvan traps calcium and magnesium ions in clay and releases sodium ions in exchange, just like a "water softener".</p>
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<p>To reverse this, you need to add calcium and or magnesium ions to exceed the Darvan level and flocculate the clay again.</p>
<p>I use calcium chloride, used to melt ice. Many use magnesium sulfate (Epsom Salts).</p>
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<p>As the calcium or magnesium flocculates the clay it will quickly "become drier", so test a small batch first to see if you need to add…</p>
<p>Darvan traps calcium and magnesium ions in clay and releases sodium ions in exchange, just like a "water softener".</p>
<p></p>
<p>To reverse this, you need to add calcium and or magnesium ions to exceed the Darvan level and flocculate the clay again.</p>
<p>I use calcium chloride, used to melt ice. Many use magnesium sulfate (Epsom Salts).</p>
<p></p>
<p>As the calcium or magnesium flocculates the clay it will quickly "become drier", so test a small batch first to see if you need to add water before adding the calcium. Pour-able slip is actually quite dry.</p>