Nonconventional cutting of plate glass using hot air jet: experimental studies

Glass is an important engineering material used in several applications because of its attractive look, chemical stability towards environment, nonporosity, and transparent nature. Its application is widely found in optomechatronic systems, windows of buildings, art work, etc. Glass cutting is the first step in the fabrication for any of its applications. Conventionally, plate glass (soda lime glass) is cut by a diamond point tool or a diamond wheel. The cut surfaces by this method are rough and wavy. Microcracks, which affect the life and quality of glass, may develop during cutting. It is difficult to cut nonstraight profiles by the conventional method and glass wastage is more. Curved profiles cannot be cut in a single step. Recently, glass cutting using laser and abrasive waterjet have been developed. Laser cutting is very costly, unsafe and leaves a heated-affected zone. Researchers have used laser cutting on glasses of thicknesses lesser than 1 mm. Abrasive waterjet requires de-ionized very high pressure water with entrained garnet abrasive. This method produces rough cut surfaces and causes wear of diamond nozzles. A novel method is developed which uses a low cost, simple, hot air jet to cut any complex profile with ease. Experimental studies are conducted to determine the variation of the cutting speed for various values of the stand-off distance, glass thickness, air temperature, and air flow rates. Glasses in the thickness range of 2–20 mm are used for the experiments. The roughness of the cut surfaces using the hot air jet and the diamond point tool is compared. The new method has produced cut surfaces of relatively higher surface finish.