Glass tempering is the process that enables you to create custom-designed glassware and decorative pieces with exceptional strength and durability. This is particularly important for applications that are subject to heavy use and abuse, such as entrance doors, railings, display cases, office partitions and dividers.
Tempered glass is 3-5 times stronger than ordinary, or annealed, glass. This makes it safer, especially for high-traffic environments where human safety is an issue.
Its strength comes from a combination of heating and cooling processes called tempering. The first step involves heating the glass beyond its softening point, which is typically 650°C. Then, the glass is quickly cooled (called quenching) in an air-quench system that blasts the surface of the glass with a high-pressure stream of nozzles.
Once the glass has been tempered, it is ready to be used in your project. However, before you begin to work with tempered glass, there are a few things you should know about it.
1. When you’re working with tempered glass, always use a sharp, flat tool that is not made from metal, so it won’t damage the glass.
2. It’s also a good idea to wear a mask that protects your mouth and nose, as well as to avoid breathing in any glass dust or debris.
3. When you’re heating your glass, don’t heat it too quickly and try to keep the temperature even. This will help prevent hotspots that can cause stress and weaken the glass.
4. When you’re cutting or drilling the glass, don’t cut into the corners.
These edges will need to be polished after you’re done, so they can’t be damaged while the glass is tempered.
5. If you’re working with large-format glass, you should try to heat it slowly and uniformly, rather than focusing all of your attention on the edge.
6. It’s also a good idea to use a wire gauze with a ceramic centre to diffuse the flame when you’re using a Bunsen burner, as this will help spread the heat evenly across the glass.
7. It’s important to test the glass after it’s been tempered, so you can see how it breaks. This will tell you if it was properly tempered and that it has the required break pattern.
8. It’s a good idea to follow a strict temperature and hold time schedule during the tempering process, so you can get the right results for your project.
9. Tempering glass is a bit like cooking – it’s not all about the ingredients and equipment, it’s about understanding the process and knowing how to control the temperatures you’re dealing with.
10. Unlike annealed glass, which can shatter into jagged shards of broken glass, tempered glass separates into small, relatively harmless pieces. This reduces the risk of injury and accidents during and after your project is completed.
If you’re not sure how to make tempered glass, consult a specialist. They can tell you what size, thickness and type of glass you’ll need for your project. They can also help you plan your design and ensure that your glass will break as safely as possible when it’s installed in your home or business.