Glazing - A Beginner's Guide!

A practical guide from choosing glaze to the final firing

Once the item has been thrown or formed, dried, and bisque-fired, it is time to glaze. This is where the surface, color, and how the item functions in practice are determined.

1. Bisque firing

Before you can glaze, your item must be bisque-fired. This means the clay is fired for the first time, usually to approximately 900–1,000 °C, depending on the clay type.

After the bisque firing, the ware is hard but still porous, which allows it to absorb the glaze in the correct way.

2. Glaze firing

All clays and glazes have a recommended firing range. It is important that these match.

• Always check the temperature at which your clay can be fired.
• Check the glaze's recommended temperature range.
  
• Lervis glaze tests for stoneware glazes shown on the website are fired at 1240 degrees.
• Never fire outside the manufacturer's specified range.

If the temperature is too low or the soaking time is shorter than 15 minutes, the glaze will not melt properly.

If the temperature is too high, the glaze may run, become dull, or ruin the shape.

Accuracy and testing here will save you both time and labor.

3. What is glaze and why is it used?

Glaze is a glass-forming coating that melts in the kiln and gives the ceramics a durable, waterproof surface.

It can be:

• glossy/satin/matt
• transparent/opaque
• Food safe ( tested and approved for contact with food and drink)
• Not food safe/not tested (should not be used on ceramics that come into contact with food and drink)

The right glaze makes the item practical and useful in everyday life.

4. Different types of glaze

Brush-on glaze

Ready-mixed glaze that is brushed directly onto the bisque-fired ware. A good choice for beginners who want to work in a controlled manner without any hassle.

How to do it: brush on three thin, even layers (let dry between layers).

→ Stoneware brush-on glaze

Powder glaze

Glaze in powder form that is mixed with water and possibly a suspending agent. Provides great flexibility and is well-suited for dipping or pouring.

Important: dip quickly. The longer you dip, the thicker the glaze layer will be. We recommend that you test different dipping times to find the result you are looking for.

→ Stoneware powder glaze

Underglaze

Used for decoration and color, often under a transparent glaze.

→ Watercolors for ceramics

→ Underglaze pencils

→ Underglaze ink pad

Safety during glazing

Glazes often contain substances that can be harmful before they have been fired. With simple routines, you work safely and securely:

• Always use a respirator when handling glaze in powder form (avoid inhaling dust).
• Use gloves when glazing. Wash your skin thoroughly if you get glaze on you.
• Do not eat or drink while glazing.
• Wipe up spills with a damp cloth.
• Try to minimize glaze waste in the drain.
• Always read the product's technical information and safety instructions.

5. How to glaze step-by-step

1) Clean the ware

The bisque-fired ware must be clean and free of dust. Wipe with a slightly damp sponge if necessary.

2) Apply the glaze

Brush, dip, or pour depending on the glaze type.

3) Keep the bottom clean

No glaze should end up on the bottom against the kiln shelf. Wipe it off, or use wax where the item stands against the kiln shelf, and leave a small margin.

4) Let it dry

The glaze must be completely dry before glaze firing.

5) Glaze fire according to recommendations

Follow the temperature instructions carefully. The color always changes in the kiln. Test and experiment to find the look you desire and learn how the glaze behaves.

 

6. Common mistakes to avoid

• Too thick a layer of glaze (the glaze runs or clumps together)
• Wrong firing temperature
• Dusty ware
  
• Glaze on the underside of your piece
• Starting with things that are too difficult, e.g., double glazing, mixing different glazes, using runny or effect-enhancing agents that require careful testing and knowledge

7. Final advice

Ceramics is a craft that rewards patience. The result does not come in the first attempt but through repetition and getting to know different glaze and clay combinations. Start simple, test your way forward, and follow the recommendations.

Once you have understood the interplay between clay, glaze, and temperature, the possibilities open up and you can start experimenting more.