Candling temperature / Drying greenware in kiln

[Magnolia Mud Research]

my additional four thoughts:

1.  Agree with @Pres.  Perhaps the automationers will add moisture meters as part of the automated part of the kilns.  I'm not holding my breath. 

2.  Keep in mind that the water trapped inside of the ware is most likely not pure water but a water solution of various materials; according high school chem textbooks the boiling point of solutions are above the boiling point of pure water and as the water is evaporated the boiling point increaces.  The point is that holding at 212 F is probably a very slow drying unless there is a large air flow through the kiln. (large is a undefined variable depending on the kiln size and the ware load) 

3.  The thickness and the coarseness of the clay body components have a strong say about when things are dry enough to start getting HOT, HOTer, and HOTest.  Raku clay bodes with coarse grog dries faster than fine porcelain clay bodies of the same thickness.  Teaching studios generally have all sorts of clay bodies, etc.   

4.   Best route is to get the ware dry prior to placed in the kiln; also design the ware to dry easy and uniformly. 

LT

[neilestrick]

On 10/1/2022 at 12:28 PM, Magnolia Mud Research said:

Raku clay bodes with coarse grog dries faster than fine porcelain clay bodies of the same thickness.

Grolleg porcelain (no ball clay) dries quickly, because it is not very tight in raw form. Porcelain bodies are only about 50% clay, so they don't hold as much water as stoneware bodies, and give up the water quickly. Fine grained white stoneware and other bodies that are high in ball clay dry quite slowly because ball clay is very fine grained and makes for a very dense body.

[Min]

1 hour ago, neilestrick said:

Fine grained white stoneware and other bodies that are high in ball clay dry quite slowly because ball clay is very fine grained and makes for a very dense body.

This. 

That's why I made a point of saying the clay I used in my test contained ball clay.