Clay Lecture

Introduction

  • Notes are for common knowledge throughout the year.

  • Vocabulary will be tested in first semester final.

What is Clay?

  • Decomposed rock, particularly granite.

  • Formed through glacial movement and decomposition of vegetation.

  • Found everywhere, such as hiking paths and backyards.

  • Exhibits crazy cracks after rain.

  • Particles are flat and adhere like a deck of cards.

  • Particles slide when wet, aiding support in both wet and dry states.

  • Key characteristic: Plasticity - shape retention after deformation.

Stages of Clay

1. Greenware

  • Very workable, still in clay form.

2. Bisqueware

  • Fired to 1,800°F.

  • Has pores, ready for glaze.

  • Permanent, transformed to ceramic.

  • Cannot revert back to clay.

3. Glazewear

  • Fired to 2,400°F.

  • Features glaze; can hold water (vitreous).

Conditions of Greenware

1. Plastic

  • Wet and flexible; ideal for joining.

2. Leather Hard

  • Stiff and retains shape; can alter and join pieces.

3. Bone Dry

  • No moisture; lightweight and fragile; can be recycled with water.

Joining Clay Together

  • Score: Create surface scratches on both pieces to increase adhesion.

  • Slip: Apply adhesive slip like glue for joining or decorating.

  • Wiggle: Move pieces together to attach edges.

  • Weld: Smooth the edges together for a firm bond.

Glazing Process

High Fire Glazing

  • Wax: Apply wax to the bottom of the pot to close pores.

  • Mix: Stir glaze thoroughly before use.

  • Dip: Immerse pot into glaze.

  • Wipe/Clean: Remove excess glaze from the pot's bottom.

Tools for Clay Work

  • Fettling Knife: For clean cuts.

  • Pin Tool: Sharp tool for scoring clay.

  • Wood Tool: Used for welding and sculpting.

  • Wire: For cutting clay.

  • Rib: Metal or wooden tool for smoothing.

  • Rasp: Grader for a smooth surface.

  • Bat: Tray for working with clay.

  • Banding Wheel: Spinning wheel for clay work.

  • Rolling Pin: For rolling out clay slabs.

Equipment Used

  • Kilns: Ovens that fire clay, run by a computer program.

  • Potters Wheel: Machine for throwing clay.

  • Slab Roller: Ensures even clay slabs.

  • Extruder: Shapes coils of clay.

  • Pug Mill: Reconstitutes/recycles clay.

Anatomy of a Pot

  • Key parts include: Lip, Neck, Handle, Shoulder, Body, Foot.