Tony Hansen's Thousand-Post TimeLineI am the creator of Digitalfire Insight, the Digitalfire Reference Database and Insight-live.com. ... more 
Example of a logo done using a polymer plate
Polymer plates are used in letter press and can still be purchased online (e.g. boxcarpress.com). Just create the artwork in a vector graphic drawing program and upload it to their website. Press it into a thin slab (using some sort of oil as a parting agent) and then attach that using slip to the
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Context: Iron Oxide Red, G1947U - Cone 10 Glossy Transparent Base Glaze, 77E06B - Plainsman Celadon Cone 10R, Polymer plates. Great for stamping into clay., Celadon Glaze Thursday 17th August 2017 
Polymer plates. Great for stamping into clay.
These are samples made by Boxcar Press. They make different depths, you need the 0.047 relief depth. While the others will press a crisp design into the clay, the shallow depth will make it difficult to avoid rubbing out the color from the recesses when you a sponging it off the top. Traditionally
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Context: Example of a logo done using a polymer plate Thursday 17th August 2017 
Measure glaze specific gravity with these? Forget it!
Glazes need to be gelled, have thixotropy. That means these things won't bob up and down to find the right place. The one on the right is completely useless, the scale is too wide. Most glazes need to be between 1.4 and 1.5 specific gravity (40-50 on this scale). That is like reading seconds on the
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Context: Specific gravity, Deflocculation Wednesday 16th August 2017 
How to make a ceramic time-bomb
This mug is pinging loudly and literally self-destructing in front of my eyes! Why? The glaze is under so much compression (the inside is pushing outward, the outside inward). Spiral cracks are developing all the way up the side. Small razor-sharp flakes are shivering off convex contours. Why? I
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Context: Shivering, Glaze fit, Glaze Shivering, Glaze Crazing Tuesday 15th August 2017 
Drip glazing and bare outsides: Deceptively difficult.
Why? Glaze fit. These are available on Aliexpress (as Drip Pottery) and they are made by a manufacturer that has a dilatometer to precisely match the thermal expansion of the glaze with the body. The inside glaze has to fit better than normal because of the absence of an outside glaze. Too low of a
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Context: Glaze at 1.7 specific gravity on green-ware. Way too thick!, Deflocculation, Glaze fit, Glaze Compression Monday 14th August 2017 
Glaze at 1.7 specific gravity on green-ware. Way too thick!
This is G2926B clear cone 6 glaze deflocculated with Darvan. Because the Darvan is thinning it, 2.5kg of powder is suspended in only 1100 grams of water (half the normal amount). While the slurry in the bucket flows well and appears like it should work, a one-second dip produces twice the desired
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Context: G2926B - Cone 6 Whiteware/Porcelain Transparent Base Glaze, Drip glazing and bare outsides: Deceptively difficult., Specific gravity Monday 14th August 2017 
Why you should not paint pure stain powders over glaze
On the left is a blue stain, right is a green. Obviously the blue is melting much better, even bleeding at its edges. On the other hand, the green just sits on the surface as a dry, unmelted layer. For this type of work, stains need to be mixed into a glaze-like recipe of compatible chemistry (a
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Context: An Overview of Ceramic Stains, Stain, Overglaze, Glaze Layering, Flux Saturday 12th August 2017 
Mug made from a cone 6 black-burning stoneware body
Black burning bodies are popular with many potters. They are normally manufactured by adding around 10% burnt or raw umber to an existing buff-burning cone 6 stoneware. Umbers are powerful colorants, they have high iron and also contain manganese (the latter being the primary source of the color).
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Context: Burnt Umber, Raw Umber, L3954B - White Cone 6 Engobe for Plainsman M390, M340, How to Liner-Glaze a Mug, Can you make a black-burning stoneware using black iron oxide?, Manganese Inorganic Compounds Toxicology Saturday 12th August 2017 
Can you make a black-burning stoneware using black iron oxide?
Iron oxide has been added to a buff burning stoneware clay and samples fired at cone 6. They contain black iron oxide (10%, 5% and 2.5%). Even at 2.5% the raw pugged body is very black and messy to work with. Did they fire black? Or even dark grey? No. We have also tried 20% (mix of black and yellow
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Context: Iron Oxide Black, Mug made from a cone 6 black-burning stoneware body Saturday 12th August 2017 
This is how New Zealand kaolin powder agglomerates
These balls are easily broken down by the propeller in a slurry mixer. But they do not break down easily in a dry mixer, even when in a mix with other materials (like silica and feldspar). They just bounce around on a vibrating screen. That means that without some sort of finishing device in the dry
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Context: New Zealand Halloysite, Agglomeration Wednesday 9th August 2017 |
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Still available for Mac, PC, Linux Interactive glaze chemistry calculations. How to reach usFrom within your account at Insight-Live.com or
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