First, use a glass knife or wind file to form a file mark at the cutting place of the glass bottle, then use cotton thread around the file mark a few times, then drip the alcohol, ignite the cotton thread about a minute, drop a few drops of water at the file mark, the bottle can disconnect along the file mark. Cut the waste newspaper into a 5mm-7mm wide strip, then soak the paper in clear water and remove it. The wet paper clings to the bottle wall around 1-4 circles along the glass bottle cutting line. Be sure to be neat at the edges of the newspaper. Ignite the wine lamp, align the bottle cutting line with the flame of the wine lamp, rotate the bottle continuously. After the bottle is hot, put it in cold water to disconnect.
Fill the glass bottle with cooking oil into the cutting line (and set aside the iron bar allowance), then insert the iron rod around the red into the oil, the glass bottle will be disconnected along the oil surface. We can also use self-made resistance wire cutter to cut glass bottles, glass tubes, light bulbs and so on. Notice when cutting: first, the resistance wire around a circle junction to leave the 1mm-2mm space to avoid short-circuiting. Second, after the glass bottle drops water, the electricity should be cut off quickly.