How to Make Venetian Glass
- 1). Melt silica in a furnace to create the liquid glass, per your furnace manufacturer's instructions. Depending on the additives you include in the silica (to adjust melting temperature, color and opaqueness), the final temperature will vary; however, glass for glass blowing generally needs to be around 2,300 degrees Fahrenheit. Once the glass reaches that temperature, gather it up on the end of the blowing pipe, rotating the pipe as you gather, to create a cylindrical-shaped blob on the end.
- 2). Place the glass blob still on the blowing pipe into the cup of the glass block and roll the pipe to create a perfectly round ball of liquid glass on the end. Return to the furnace and add more molten glass. Repeat the process until you have enough glass on the end of the blowing pipe to complete your project.
- 3). Blow into the end of the blowing pipe. Cover the mouth hole of the blowing pipe with your thumb, to trap the air inside. The heat from the pipe and the glass will cause the air to expand and expand the molten glass on the end. Continually rotate the pipe to ensure the piece remains uniform. If the piece has not expanded enough, reheat the glass in the glory hole of the furnace and blow again.
- 4). Create the final shape of the piece. The steps needed to complete the final shape of your piece vary greatly depending on what you are making. However, the process will include shaping the hot glass with glass-working tools, such as tongs, paddles or folded, wet newspapers, while rotating the pipe. As the glass cools quickly, it's important to reheat it as necessary in the glory hole.
- 5). Transfer the piece to the punti and finish the edge of your piece. Use a blow torch to apply heat to only a small area of the piece. Gently tap the piece off the punti and place it into the annealer, which allows the piece to be slowly cooled, to prevent cracking.
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