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Tony Hansen's Thousand-Post TimeLine

I am the creator of Digitalfire Insight, the Digitalfire Reference Database and Insight-live.com. ... more

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Is this your record keeping system?

Is this your record keeping system?

Keeping your valuable notes like this? Recipes? Test results? Are your pictures lost in a cellphone with no keywords or connections to anything? If you test and develop you need to organize in a way that a book cannot do. Like link recipes to each other and other things like pictures and firing ... more

Monday 14th January 2019

Trafficked online recipes waiting for a victim to try them!

Trafficked online recipes waiting for a victim to try them!

Last week a customer came to buy materials to mix these recipes she found online. Then we had a closer look. Many have 50+% feldspar/Cornwall/nepheline with little dolomite or talc to counteract their high thermal expansion, these are guaranteed to craze. Many are high in Gerstley Borate, it will ... more

Monday 14th January 2019

Two G2571A Bamboo color versions at cone 10R

Two G2571A Bamboo color versions at cone 10R

These mugs are Plainsman H450. Both have a black engobe (L3954N) applied to the insides and half way down the outside during leather hard stage (the insides are glazed with Ravenscrag silky matte and G1947U over the black engobe). The bamboo glazes can thus be seen over the black (upper half) and ... more

Monday 7th January 2019

G1947U Clear and Ravenscrag Silky Matte glazes on L3954N black engobe

G1947U Clear and Ravenscrag Silky Matte glazes on L3954N black engobe

Fired at cone 10R. Clay is Plainsman H450. The black engobe was applied at leather hard stage. The clear glossy glaze over it on the inside produces a deep and vibrant hue. The black engobe extends downward on the outside and it greatly darkens the glaze applied over it. On the edges of contours, where the matte glaze is the thinnest, the engobe turns the color almost black.

Monday 7th January 2019

A vitreous sculpture clay. Vitreous enough for functional ware!

A vitreous sculpture clay. Vitreous enough for functional ware!

The chocolate brown burning super-plastic base clay (to which 20% coarse grog is added) matures at cone 6. Yet this is a cone 10R body. The grog stabilizes the fired matrix enough that it stands up in the kiln. And it fires to a dense product that can withstand any weather. Any porosity that can be ... more

Monday 7th January 2019

A cure for long-time Gerstley Borate sufferers

A cure for long-time Gerstley Borate sufferers

These are various different terra cotta clays fired to cone 04 with a recipe I developed that sources the same chemistry as the popular Worthington clear (50:30:20 GB:Kaolin:Silica) but from a different set of materials. They key change was that instead of getting the B2O3 from Gerstley Borate I ... more

Friday 21st December 2018

We fight the dragon that others do not even see

We fight the dragon that others do not even see

There are thousands of ceramic glaze recipes floating around the internet. People dream of finding that perfect one, but they often only think about the visual appearance, not of the usability, function, safety, cost or materials. That resistance to understanding your materials and glazes and ... more

Friday 21st December 2018

How much feldspar to using in a Grolleg porcelain

How much feldspar to using in a Grolleg porcelain

These are porcelains are made using Grolleg kaolin. P700 (Plainsman) has 19% G200 Feldspar and Coleman (popular among potters in the US) has 31% (P700 switches the 12% to kaolin). Although the Coleman porcelain is more vitreous (top right) it is not more translucent. But it is a lot more problematic ... more

Thursday 20th December 2018

The specific gravities on two commercial underglazes might shock you

The specific gravities on two commercial underglazes might shock you

AMACO and Crysanthos. 1.26 (67.5% water) and 1.22 (68% water)! The former is well below their recommended specific gravity of 1.4 (it still paints well but needs more coats, and more time to dry and apply them). Strangely, the Crysanthos, although having a lower specific gravity is more viscous and ... more

Wednesday 19th December 2018

Here's how we used to record test results before we got insight-live.com

Here's how we used to record test results before we got insight-live.com

A potter is testing glazes on a new clay body. But this generates a lot of data, how is a person to keep track of it all? This is how we used to do it. An account at Insight-live.com is the new place to organize this. There is room for thousands, even millions of recipes, pictures, notes, firing ... more

Wednesday 19th December 2018

Contact Us:

Use the contact pages within or outside your account at Insight-Live.com


Test, Document, Learn, Repeat in your account at insight-live.com

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Chemistry plus physics. The on-line successor to desktop Insight. Get an account for as little as $15. It does so much more.

Conquer the Glaze Dragon With Digitalfire Reference info and software

Still available for Mac, PC, Linux

Interactive glaze chemistry calculations (legacy, no longer supported)


What people have said about digitalfire

• All your info on glaze chemistry and material characteristics are very informative and great catalysts for pushing me to take things a bit further. Most appreciated.

• Your site is one of the most unusual sites I have encountered since I began exploring ceramics on the web. I am a student in a 2 year pottery program, and would like nothing better than to understand glazing from the very beginning of my career as a potter...It is pretty overwhelming. To tell you the truth, you almost come off as a Southern Baptist Revival Preacher the way you rant and rave against the "Dragon." It is what got my attention, however, and I appreciate the quality of your work, but it is very overwhelming.

• I have found the glaze information on your site really helpful for quite some time now. I like the way that there is an emphasis on problem solving and understanding how things work, rather than just offering recipes that might work.

• I love the site. I use it all the time at the Clay Business, and I feel like I have not even touched the surface.

• I normally do not comment on articles I find, but this is amazing. Thank you so much for providing this information! I am a ceramics student in my BFA year, and this is the most comprehensive and helpful information I have found on creating a porcelain casting slip.

• I want to comment. This is the most complete site about ceramics that I have ever seen.

• omg i just discovered your page this is like breaking bad for ceramics, learning how to cook. this is a great page thanks !


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What people have said about Insight-Live

• I love your software and I really appreciate you being there when I need help. Keep on being amazing. I am still enjoying insight every day. You were right - having it in the cloud is a huge advantage.

• I keep telling people that I just found the best ceramic website on the internet. Paid for an account on insight live.

• First i'd love to thank you for all the info you provide on digitalfire. it is an absolutely amazing resource and the way that you explain glaze chemistry/reactions has really helped expand my practice...I crave understanding and wisdom.

• I simply want to let you know that the digitalfire reference library is a treasure. Every time I look it up I learn something new, and I have a hard time to tear myself away. I have a number of books on my shelf, but if I had to choose just one reference source, it would be digitalfire. There is an enormous amount of work behind all the entries in the library. For me, it has enriched my practice and helped me advance in a way that cannot be measured.

• Your site is amazing and your videos too. Such an inspiration.

• I spent most of yesterday playing with the “new” (to me) version of insight on line. I love it, it is faster and eventually easier to use. And by the way, thank you for creating and maintaining the enormous data base of ceramic materials and making it available for anyone to use. What a wonderful gift to all of us interested in ceramics.

• I should mention beforehand that you, as well as Insight, have become the “go to” reference for all technical aspects of my work and those of other potters I know. It has become an invaluable resource. Congratulations on your academic approach to everything ceramic.


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