FAQDrying and Firing using electric oven Login

Drying BronzClay

You will need to dry your BRONZclay™ piece thoroughly before firing to prevent moisture in the clay from expanding and creating defects during firing.
To dry the piece, gently place it on a warming surface such as a coffee mug warmer. When dry, the clay will be leather-hard, making it flexible and amenable to finishing touches such as filing, drilling, sanding and carving.
After firing, this work is more time-consuming, so take advantage of this pre-fired stage to do as much of your detailed finishing work as possible.

Firing BRONZclay™ is a two-step process that uses low heat to prepare the kiln's atmosphere, then high heat to sinter the alloy. BRONZclay must be fired in a kiln. During firing, the non-toxic binder vaporizes, leaving a solid, pure bronze object.
Note: Make sure your piece is completely dry before firing; it's not a problem for the piece to dry for weeks before firing, but firing a piece while it's still damp can cause the moisture to expand, creating blisters.

To reduce oxidation, the BRONZclay™ piece(s) must be surrounded by activated carbon during firing. The coconut shell–based carbon produces a light patina color; the coal-based, acid-washed carbon produces a colorful, more intense range of patinas.

How to fire BRONZclay™:

  1. Spread 2.5cm of activated carbon granules on the bottom of a stainless steel firing pan.
  2. Place the piece on top of the layer; if firing two or more pieces, leave at least 1,5cm between pieces; leave more if the pieces are larger.
    Note: Most kilns are cooler in the front near the door, so the front of your firing pan will be cooler than the back and sides. Compensate for this by placing pieces closer to the sides and back of the firing container. If you're using a top-loading kiln, there's no need to adjust.
  3. Pour more activated carbon granules on top of the piece until the container is full, making sure there is at least a 1.5cm layer of granules on top of the piece. If you are firing several pieces in layers, make sure there is at least 1.5cm of space between the vertical layers as well.
  4. Cover the firing pan with its lid and place it in the kiln on stilts to allow good heat circulation

BRONZclay™ FIRING SCHEDULE

  1. For pieces 3mm (6 cards) thick or less: Ramp at 500°F/hour to 1550°F and hold for 2 hours (total firing time, including ramp-time, will be between 4 and 5 hours).
  2. For pieces thicker than 3mm (6 cards): Ramp at 250°F/hour to 1550°F and hold for 3 hours (total firing time, including ramp-time, will be about 9 hours). The firing schedule for thicker pieces will work fine for thin pieces should you have both thicknesses in your firing pan. WARNING: The firing pan will be extremely hot; do not touch! Allow the pan to cool completely before removing the lid. We recommend wearing heat-resistant gloves while removing the firing pan.
  3. The firing pan should be allowed to cool completely before removing it from the kiln; however, if you need to use your kiln again right away, you can move the pan to a heat-resistant surface (e.g.: a soldering pad or ceramic tile) and allow it to cool there.
  4. Once the firing pan and carbon have cooled, remove the BRONZclay™ pieces from the carbon bed and place them on a heat-resistant surface to finish cooling. You can re-use the activated carbon until you notice it starting to break down (broken grains and a sooty appearance). Note: If there are no stones embedded in the piece, it can be quenched in water.
The stainless steel lifting fork is ideal for removing a hot firing pan from your kiln. Gently slide the fork around the bottom half of the firing pan and lift the fork until the tines engage the lip at the top of the pan. Carefully lift the pan from the kiln and set it on a heat-resistant surface to cool.
Note: The fork will only fit around the narrow side of the firing pan.