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3D Print a Test of the Beer Bottle Neck
3D Printing a Clay Cookie Cutter-Stamper
A 3-minute Mug with Plainsman Polar Ice
A Broken Glaze Meets Insight-Live and a Magic Material
Accessing Recipes from "Mid-Fire Glazes" book in Insight-Live
Adjusting the Thixotropy of an Engobe for Pottery
Analysing a Crazing, Cutlery-marking Glaze Using Insight-Live
Compare the Chemistry of Recipes Using Insight-Live
Connecting an External Image to Insight-Live Pictures
Convert a Cone 10 Glaze to Cone 6 Using Desktop Insight
Create a Synthetic Feldspar in Insight-Live
Creating a Cone 6 Oil-Spot Overglaze Effect
Creating Rules for Calcium Carbonate - Wollastonite Substitution
Design a Triangular Pottery Plate Block Mold in Fusion 360
Desktop Insight - Difficult Formula to Batch Calcuations
Desktop Insight 1A - Compare Theoretical and Real-World Feldspars
Desktop Insight 1B - Turn a Feldspar Into a Glaze
Desktop Insight 1C - Substitute Wollastonite for Whiting in Glazes
Desktop Insight 2 - Creating a Matte Glaze
Desktop Insight 3 - Dealing With Crazing
Desktop Insight 4 - Add a Native Material to MDT, Build a Glaze
Desktop Insight 5A - Glaze Formula to Batch Calculations
Desktop Insight MDT: Adding a Material
Desktop Insight: Maintain an MDT as a CSV File in Excel
Digitalfire Desktop INSIGHT Overview Part 1
Digitalfire Desktop INSIGHT Overview Part 2
Enter a Recipe Into Insight-live
Entering Shrinkage/Porosity Data Into Insight-Live
Getting Frustrated With a 55% Gerstley Borate Glaze
How I Fixed a Settling Glaze Slurry Using Desktop Insight
How I Formulated a Cone 6 Silky Matte Glaze Using Insight-Live
How to Add Materials to the Desktop Insight MDT
How to Apply a White Slip to Terra Cotta Ware
How to Paste a Recipe Into Insight-live
Importing Data into Insight-live
Importing Desktop Insight Recipes to Insight-live
Importing Generic CSV Recipe Data into Insight-Live
Insight-Live Meets a Silica Deprived Glaze Recipe
Insight-Live Quick Overview
Liner Glazing a Stoneware Mug
Make a precision plaster mold for slip casting using Fusion 360 and 3D Printing
Make test bars to measure pottery clay physical properties
Making ceramic glaze flow test balls
Manually program your kiln or suffer glaze defects!
Mica and Feldspar Mine of MGK Minerals
Predicting Glaze Durability by Chemistry in Insight-Live
Preparing Pictures for Insight-live
Remove Gerstley Borate and Improve a Popular Cone 6 Clear Glaze
Replace Lithium Carbonate With Lithium Frit Using Insight-Live
Replacing 10% Gerstley Borate in a clear glaze
Signing Up at Insight-live.com
Signing-In at Insight-live.com
Slip cast a stoneware beer bottle
Subsitute Gerstley Borate in Floating Blue Using Desktop Insight
Substitute Ferro Frit 3134 For Another Frit
Substituting Custer Feldspar for Another in a Cone 10R Glaze Recipe
Substituting Materials by Weight: Why it does not work!
Substituting Nepheline Syenite for Soda Feldspar
Thixotropy and How to Gel a Ceramic Glaze
Use Insight-live to substitute materials in a recipe
Using Recipe Libraries With Desktop Insight

Substituting Materials by Weight: Why it does not work!

Wollastonite is 50:50 CaO:SiO2. So why not just substitute 40 wollastonite for 20 calcium carbonate and 20 silica? The answer will help you see reason why we make such a big deal of glaze chemistry.

D. Desktop Insight


Click here to watch this at youtube.com or click here to go to our Youtube channel

Let's consider a puzzling question using desktop Insight. Transcription of this video follows.

Double-click wollastonite. Has 1:1 CaO:SiO2
Show recipe window with recipe 1 as 20 whiting, 20 silica, 40 feldspar, 20 kaolin; recipe 2 as 40 feldspar, 20 kaolin, 40 wollastonite.
I have it in Insight in place of Calcium Carbonate and Silica. But CaO goes up, while the SiO2 goes down. Why?

We are dealing with a viewpoint issue: we weigh material powders, but formulas compare molecule numbers.

Oxide dialog demonstrates a key point:
We know what each oxide does in a fired glaze.
But we relate the degree of influence to their #s
So 10 grams of Li2O is going to do alot more fluxing than 10 grams of BaO!
SiO2 and CaO are about the same: But these are oxides, not materials.
K2O/Na2O same effect in glazes, but by #s only
BaO/SrO: Similar fluxing power by molecules, not weight.

Another dynamic: LOI (compare Wolly:Whiting carbonates in MDT dialog) Even if I could deem the powders to contribute equal amounts of CaO, this messes up that assumption.

Yet another dynamic: These formulas recalculate to flux unity. Changing the amount of any oxide changes everything. It is like percentage in recipe.

To level the playing field when substituting materials we use no-unity.
Change a material supplying one oxide: only 1 changes

With noUnity lets compare the recipes
(CaO is way up, SiO2 up a little, expected)

So, lets do this right and substitute 20 calcium carbonate for wollastonite.

Notice that to replace 20 whiting I need 23.4 wolly and to reduce the silica by 12.
Need to retotoal.

Have you seen the other tutorial videos on this at http://digitalfire.com/university/index.html?

Links

Media Desktop Insight 1C - Substitute Wollastonite for Whiting in Glazes
Compare calcium carbonate (whiting) with other sources of CaO (dolomite, wollastonite, frit), learn to understand the chemistry differences between materials and then substitute wollastonite for whiting in a specific recipe.
Media Creating Rules for Calcium Carbonate - Wollastonite Substitution
How to use Digitalfire Insight software to determine how much wollastonite to add and silica to remove to substitute for calcium carbonate in the glaze. Create substitution rules.
Glossary Material Substitution
Material substitutions in ceramic glaze and body recipes must consider their chemistry, mineralogy and physical properties
Glossary Oxide Formula
In ceramics, the chemistry of fired glazes is expressed as an oxide formula. There are direct links between the oxide chemistry and the fired physical properties.
Glossary Formula Weight
Glossary Chemical Analysis
In ceramics, raw material chemistry is expressed a chemical analyses. This is in contrast to fired glaze chemistries which are expressed as oxide formulas.
Glossary Glaze Chemistry
Glaze chemistry is the study of how the oxide chemistry of glazes relate to the way they fire. It accounts for color, surface, hardness, texture, melting temperature, thermal expansion, etc.
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