August 30, 2011

Bone China Slip Trials

Bone China Slip Trials: Ten Kilos

Here in the rcboisjoli studio, we've been weighing, measuring, recording and mix mix mixing. We've completed our first batch of Bone China Slip. We did a larger ten Kilo batch as we found small batches were just too hard to get just right. Most recipes call for 100 pounds of clay to start with. 
We definitely have come along way with our slip knowledge. We've experimented with Soda Ash, Sodium Silicate and Darvan #7 to get the batch just right. Ultimately we added a tad too much water, (our Specific Gravity is about 16.8) and we had to increase the deflocculants by about 30% from normal clay body guidelines. We'll be preparing a technical document for anyone interested in making your own slip soon, once we're sure it's working just fine.

 All those scribbles are important! Each addition was carefully recorded and noted. We stared at that bucket for way too long. rcboisjoli is looking to invest in a real mixer, one on a stand.


  1. Have you worked it out yet?

  2. We got a pretty good bone china going here:

    But we’ve also just got a fine English Kaolin to do a another round of tests. We’re hoping to get a finer, whiter, bone-china-er slip soon.