How the slip casting calculator works
The arithmetic behind a plaster batch, a casting slip at the right gravity and the time a cast spends in the mould: volume-additive plaster, Brongniart's formula and the square-root casting law.
Clay body Read →
Blog
Pottery notes
Posts on pottery: materials, technique, kilns, glazes, and the physics behind the craft. Written to help potters get better work out of the studio.
The studio looks clean, and the air is not
Burns heal. Silicosis does not. What respirable silica is, where it comes from in an ordinary studio, why cleaning wet beats a thorough weekly sweep, and how to find out whether the respirator you already own is sealing.
Studio Read →
The controller reads 1222 °C, and the cone disagrees
Temperature is instantaneous, heat work is cumulative, and only one of them decides whether your glaze melted. What a pyrometric cone measures, how heating rate moves the target, and how to catch a thermocouple that has started to lie to you.
Kilns Read →
Digging your own clay, and writing the data sheet yourself
Where clay hides, the five field tests that take a jar of water and a bottle of vinegar, and the one firing that decides everything else. Prospecting is the testing discipline you already owe your materials, applied to one that arrives unlabelled.
Raw materials Read →
What makes clay plastic, and why it shrinks
Plastic clay bends without cracking and keeps the shape you give it. Flat platelets slide on films of water, and the same films explain why clay shrinks as it dries.
Clay body Read →
Why glazes craze, and why a perfect fit is the wrong goal
Crazing, shivering, and the quiet compression a good glaze lives under: what the cracks are telling you, and why a perfect fit is the wrong goal.
Glaze Read →
Designing a kiln brick by brick
How to use the kiln builder, and the masonry it models: running bond, sprung arches, catenaries, and round walls, with the counting that traces every brick back to the saw.
Kilns Read →
How the element calculator works
From Ohm's law to the Kanthal design procedure: wire diameter, hot resistance, coil geometry, and the surface load that decides how long a heating element lasts.
Kilns Read →
How the kiln energy calculator works
Inside the energy calculator: a coupled steady-state heat-loss solver, temperature-dependent conductivity, two ways to count a thick wall, and how loss becomes the power and fuel your kiln needs.
Kilns Read →
What 60 electric kilns tell you about power
A survey of 60 production electric kilns, the physics behind the kiln builder, and where Olsen's quick formulas land relative to what is on shop floors today.
Kilns Read →