What temperature is raku fired at?

Raku is typically fired to 1800-1900°F (cone 06 to cone 04). This is much lower than stoneware (2200-2400°F). The key isn't hitting an exact temperature — it's watching the glazes. When they look glossy and molten through the peephole, the pieces are ready to pull.

Is raku pottery food-safe?

No. Raku pottery is not food-safe and should not hold liquids for drinking or eating. The low firing temperature leaves the clay porous, and the reduction process creates a surface that can harbor bacteria. Raku is strictly decorative. Use it for art pieces, vases with a liner, and display.

What makes raku glazes different?

Raku glazes are formulated to mature at low temperatures and create dramatic effects during reduction. Copper-based glazes produce metallic lusters and iridescent colors. Crackle glazes develop a network of fine cracks that absorb carbon smoke, creating a dark web pattern on a light surface. These effects are impossible with standard high-fire glazes.

Is raku firing dangerous?

Raku involves open flames, red-hot ceramics, and combustible materials — it requires serious safety precautions. Wear heat-resistant gloves, safety glasses, natural-fiber clothing (synthetics melt), and closed-toe shoes. Work outdoors only. Have a fire extinguisher and water bucket nearby. Never do raku alone — always have a partner.

Can you raku fire regular clay?

Regular stoneware or earthenware will likely crack during raku. The rapid temperature changes (pulling from 1800°F kiln, reduction, then water quench) create extreme thermal shock. Raku clay contains high grog content specifically to withstand this. Always use clay labeled for raku.

Raku Pottery Firing — Process, Glazes & Safety Guide

What Makes Raku Special

Most pottery is fired slowly, cooled slowly, and opened days later. Raku throws all of that out. You fire fast, pull pieces from a glowing kiln with tongs, drop them into combustible materials, and watch fire do the decorating. Every piece is a one-time event — no two raku firings produce identical results.

Stephen Jepson's raku work spans decades. His video lessons cover the full process — from choosing the right clay body to pulling pieces safely, to understanding why certain glazes produce copper flashes, crackle patterns, or matte black surfaces.

The Raku Firing Process

Step 1

Bisque Fire First

Fire raku clay pieces to cone 06 (1828°F) in a regular kiln. This hardens the clay enough to handle and accept glazes while keeping it porous. Use clay with high grog content — it must survive extreme thermal shock later.

Step 2

Apply Raku Glazes

Brush or dip raku-specific glazes onto bisqueware. Copper glazes produce metallic lusters. Crackle glazes create fine web patterns. Apply evenly and generously — raku glazes are thick and bold by design.

Step 3

Fire to 1800-1900°F

Heat the raku kiln (propane-fired, top-loading) for 45-90 minutes. Watch through the peephole — when glazes turn glossy and molten, pieces are ready. Don't rely on temperature alone; visual cues matter most.

Step 4

Pull from the Kiln

Using long metal tongs and heat-resistant gloves, extract each glowing piece. Move quickly and deliberately. The window between kiln and reduction chamber is seconds — hesitation means the piece cools too much for proper reduction.

Step 5

Reduction Chamber

Drop the red-hot piece into a metal trash can filled with newspaper, sawdust, or leaves. The material ignites instantly. Seal the lid to cut off oxygen. This starved-oxygen environment (reduction) is what creates raku's metallic and smoky effects.

Step 6

Quench and Clean

After 15-20 minutes, remove the piece with tongs and plunge into water. The thermal shock locks in the crackle pattern as carbon fills the cracks. Scrub off carbon residue to reveal the final surface. Each piece is a surprise.

Raku Safety — Non-Negotiable

Work outdoors only — Open flames, smoke, and fumes require open air. Never raku indoors or in a garage.
Heat-resistant gloves — Welding gloves rated to 1,000°F minimum. Regular oven mitts will not protect you.
Natural-fiber clothing — Cotton or leather. Synthetic fabrics melt onto skin near high heat. Long sleeves, closed shoes.
Safety glasses — Sparks, ash, and radiant heat. Protect your eyes at all times near the kiln.
Fire extinguisher — Within arm's reach. Combustible materials and open flame demand it.
Never work alone — Always have a partner. If something goes wrong, you need someone who can help immediately.

Popular Raku Glaze Effects

Copper matte — Produces rich copper, bronze, and iridescent surfaces. The most iconic raku finish.
Crackle (crazing) — A clear or white glaze that develops a network of fine cracks filled with carbon smoke. Elegant and dramatic.
Horsehair raku — No glaze. Lay horsehair or feathers on the hot piece. They burn instantly, leaving dark organic line patterns.
Naked raku — A resist slip under the glaze. The glaze peels off after reduction, leaving a smoky, matte surface with crackle patterns in the bare clay.

Raku Pottery Firing