How to Make Sheet Glass

Sheet glass is any type of glass that's distributed as a flat plane, as opposed to glass that forms a container. Sheet glass typically consists of silica sand, soda and limestone and is usually made with the float glass process, but there are other processes such as rolling, fusion overflow, broad sheet, and crown glass.

Things You'll Need

• Blowpipe
• Glassmaker furnace
• Iron ladles
• Iron plate
• Iron shears
• Limestone
• Molten glass
• Molten tin
• Pontil
• Rolling table
• Silica Sand
• Soda
• Tapered trough

Instructions

1. Make the molten glass. There are many recipes for glass but a typical composition is 63 percent silica sand, 22 percent soda and 15 percent limestone. Mix these ingredients thoroughly and heat to about 1,200 degrees Celsius until they melt to form molten glass.

2. Use the float process to make sheet glass. Cover a long, flat bed of molten tin with molten glass. The glass is slowly cooled until it can be lifted out of the tin bath and cooled down to room temperature. This method produces glass with extremely flat, even surfaces.

3. Make sheet glass by rolling it. Use iron ladles to pour the molten glass from large iron ladles onto a cast-iron rolling table. An iron roller then rolls the sheet flat until it attains the desired thickness. This method is similar to that used for making plate glass.

4. Produce glass with pristine surfaces using the fusion overflow process. Pour the molten glass down a tapered trough until it fuses to form a single sheet. This method is commonly used to make flat screen displays.

5. Blow glass into flat sheets. This technique uses a blowpipe to blow the glass into an elongated shape. Cut the ends off and split the resulting cylinder with shears. Place the sheet onto an iron plate and flatten it into the shape and thickness desired.

6. Make crown glass. Blow the glass into a hollow globe and transfer it to a pontil. Reheat the glass and spin it into a flat disk (bullion) about 6 feet in diameter. Cut the bullion into the desired shape and thickness.

References

• Chemistry Explained