The cutting of glass
Glass cutting
Glass is a special material that can also be referred to as a supercooled liquid. Although it is hard and rigid, it is disordered at the molecular level and not crystalline. This means that there are no defined directions or axes within the glass. A crack can start anywhere and propagate in the direction dictated by local stress. This property allows for glass "cutting".
The essence of glass cutting is to create a crack on the surface of the glass and then break the glass along this crack. The tool required for glass cutting is a small cutting wheel made from hardened tool steel. This cutting wheel can be used in both manual glass cutters and mechanized glass cutting tables. The process is simple but requires precise tools.
The small cutting wheel seemingly just scratches the surface of the glass, but it actually creates deep micro-cracks within the glass. These micro-cracks are aligned with the pressure force of the wheel, and if tensile stress is applied, the glass will break exactly along this line. The cracks caused by the cutting wheel are so effective that sometimes the glass will break on its own along the scratch due to temperature changes. This method allows for extremely effective and precise glass cutting.
In mechanized glass cutting, the cutting head drips glass cutting fluid onto the cut, which helps to break down the silicon-oxygen bonds and makes it easier to break the glass. This fluid facilitates easier breaking of the glass along the crack. A similar principle is applied in manual glass cutting, where old glass cutters often moisten the groove before breaking.
Quality of glass cutting
An uneven cut can significantly reduce the lifespan of a window (it may crack more easily), cause difficulties in later processing, affect the aesthetic appearance of the final product, or even cause injury. The hallmark of quality glass cutting is that it takes into account the glass thickness, type, any coatings or protective films on the glass surface, etc., and accordingly adjusts the pressure applied by the cutting wheel and the cutting speed, as well as any necessary additional operations.
For insulating glass, it is necessary to remove coatings from the future edge sealing area, while for laminated glass, precise cutting and proper equipment on cutting tables are crucial for separating the foil.
At CE Glass, we use the most advanced automatic cutting tables for glass cutting, allowing for precise creation of square, round, elliptical, curved, and wavy shapes. Special shapes can also be made using glass milling techniques.
Our goal is to extract useful glass pieces from our stock with minimal cutting losses.