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Tony Hansen's Thousand-Post TimeLine

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

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Over deflocculated vs. under deflocculated ceramic slurry

The slip on the right has way too much Darvan deflocculant. Because the new recipe substitutes a large-particle kaolin for the original fine-particled material, it only requires about half the amount of Darvan. Underestimating that fact, I put in three-quarters of the amount. The over-deflocculated ... more

Wednesday 23rd October 2019

Kiln Firing Curve Recorder - In Development

So many glazes appear as they do because of the firing schedule (especially the cooling curve). Imagine getting an awesome result out of a kiln and not knowing (or being able to replicate) the exact firing schedule that produced it. This device reads and records the temperature once per minute. It ... more

Wednesday 23rd October 2019

Low fire glaze with the Al2O3 and SiO2 of a cone 6 glaze

Look at how fluid G3879 is at cone 06 even though it has the Al2O3 and SiO2 of a cone 6 (or even cone 10 glaze)! It have found that glazes with lots of boron can tolerate amazingly high levels of Al2O3 and SiO2 and still melt very well. And they create many options to lower thermal expansion that ... more

Wednesday 23rd October 2019

By the magic of delflocculation, this powder will mix into that water and still fit in the container

This is 1100cc of water and 3000 grams of M370-2 casting. Amazingly, it is possible to get all that powder into that little bit of water. And still fit in the container (2250cc) and still produce a very fluid slurry for casting. How is this possible? That water has 11 grams of Darvan 7 deflocculant ... more

Wednesday 23rd October 2019

RedArt Slip vs. Albany Slip vs. Alberta Slip melt flow, coverage comparison

These three melt flows and mugs were fired at cone 6 (using the C6DHSC firing schedule). The recipe is GA6-B (80% slip, 20% Ferro Frit 3195). The center flow and mug (M340) employ original Albany Slip in the recipe. The one on the far left uses an Albany Slip substitute that was developed by ... more

Wednesday 23rd October 2019

Sedimentary clays are a whos-who of the periodic table

These are the results of an elemental composition study of a sedimentary clay. The first column of numbers is ppm (parts per million), divide them by 10,000 to get percent (the Fe, for example, is 50,868 or 5.1%). The second column is +/- error. Notice that this test does not sense boron or lithium, they require a different method.

Wednesday 23rd October 2019

The glorious colors of G2934Y glaze

These are made from Plainsman M370 casting and fired to cone 6 using the PLC6DS firing schedule. There is a caution with thin cast ware: If walls are not thick enough to provide the porosity to be able to absorb all the water from the glaze, then the slow-drying glaze could crack and produce crawling during firing. Thinner pieces (not shown) did crawl in this firing.

Wednesday 23rd October 2019

Pottery made from cremation ash, increasingly popular!

As you can see from the search, this is becoming "a thing". The ash is being incorporated into both clay bodies and glazes. The ash of pets and humans. If you are a potter wondering about doing this here are a few tips. Do testing, better to use up some of the ash for that than have to throw away ... more

Wednesday 23rd October 2019

Why throw on a plaster bat when making larger pieces?

Even drying, that's why. As soon as was practical I covered the piece with a cloth and then put it inside a garbage bag. While that put the upper section a little ahead in drying, over night the base caught up as the plaster sucked the water out. In the mourning I lifted it off without having to cut ... more

Tuesday 22nd October 2019

Alberta Slip as-a-glaze at cone 10R

This is 100% Alberta Slip (outside) on a buff stoneware (left) and iron stoneware (right) fired to cone 10R. The glaze is made using a blend of roast and raw (as instructed at the product page). Alberta Slip was originally formulated during the 1980s (using Insight software) as a ... more

Monday 21st October 2019

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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)

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What people have said about Insight-Live

• First off, I want to thank you for building Digitalfire. It is an incredibly valuable ceramic resource.

• I love all the tips and insight live is a lot of fun as well as being an amazing tool. Thanks

• I just wanted to express my appreciation for digital fire. It's an invaluable resource that I've been using since I was 18 years old (more than a decade). Keep up the amazing work.

• I am a production potter and I have been using your website for information, and I have made many improvements from articles posted on this site.

• BTW, thanks for creating such a great site.

• Love Insight-live. Have been using it a few months and now that I know my way around a bit, I have come to rely on it. Love having a web based program, since I bounce between Windows on several machines and also a Chromebook.

• I have longed admired your website, and everything you've contributed to better understanding ceramic technology.

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