GlazeGlaze

What you need to know before What you need to know before you applyyou apply

What is Glaze?

• Glaze:– a vitreous coating to a

ceramic material whose primary purposes are decoration or protection

– consists of ground glass and color pigments that when heated to extreme temperatures in a kiln create a non-porous surface.

What is in glaze?

Silica: Finely ground glass, has a high melting point

Flux: Lowers melting point of silica. I.e. Lead

Alumina: Gives glaze stability and adhesion.

Coloring oxide additives: Tin: White Iron: Brown Cobalt: Blue Copper: Green Vanadium:

Yellow

Glaze Preparation

• Dry ingredients and water are mixed together to form a smooth, even consistency. Similar in appearance to a very thick cream.

Proper glaze mixing

• Stir the glaze thoroughly with a whisk or your hand in the bucket before applying. Check the bottom of the bucket to check to feel if the glaze is thoroughly mixed from top to bottom.

• The mixed glaze should be the consistency of thick cream.

If Lumpy, continue to mix or strain

If thin, ask for my assistance

Before glazing… Wax Resist!

• Creates a barrier that resists glaze adhesion to the bisque ware. – Why is this important?

• Rules:– Wax bottom 1/4” of

piece– After glazing, wipe

excess glaze from waxed area with sponge

Technique 1 Dipping• Immersing piece

directly into glaze– Wax foot– Dip and hold for 3

seconds (Single color dipping only requires one dip)

– Let drain, fill finger (tong) marks when dry

– Wipe excess glaze off of foot

Window dipping

Double window dipping okay

Be careful with triple window

dipping!

Technique 2 BrushingTechnique 2 Brushing

•Best technique for hand-built work

•Nice for piece with multiple areas of

different colors

•3 medium coats as a rule

•Some glazes may require up to 6 coats

•We will use mostly this method of applying glaze

Technique 3 Pouring

Best for large bowls, platters, and plates

Must use a container to collect excess glaze

This is an advanced technique and we will generally have no need for it in C/S/3D I

Technique 4 SprayingSprayed on glaze with

specialized equipment in spray booth

After applied, do not touch!

Nice for fading colors together

We used to have a spray booth!

Special Techniques Sponge PatterningSpecial Techniques Sponge Patterning

• A sponge can be cut to give a raised pattern look

• Pattern the piece with a contrasting glaze

Special Techniques Wax Resist DesignSpecial Techniques Wax Resist Design

• Brush design on bisque ware with wax

• Dip, paint, pour, or sponge on the color over the wax design

Special Techniques UnderglazeSpecial Techniques Underglaze

• Brush multi color design on bisque ware with sumi brush and cover with clear or semi-opaque glaze

Special Techniques Sumi OverglazeSpecial Techniques Sumi Overglaze

• Brush single color design on glazed piece with sumi brush

• Use banding wheel to paint straight lines

Special Techniques Oxide decorationSpecial Techniques Oxide decoration

• Red or Black iron oxide wash can enhance the texture of the piece.

• Not a glaze, and is not glossy

• Apply, and then wash off of highlights

Special Techniques LustersSpecial Techniques Lusters

• Very low fire metallic

• Applied over previously glazed work

• Expensive!