Cutting of fine glass tubes and rods. When cutting the thin glass tube and rod with a diameter of 5mm-10mm or less, it must first be placed flat on the edge of the table, and the edge of the triangular file, grinding wheel blade (or the newly broken porcelain bowl piece) is pressed vertically at the place where the glass tube is to be cut off, pushed forward forcefully, so that the file mark reaches 1/3 or 1/4 of the circumference of the tube, pick up the glass tube (rod), and the thumbs of the hands are against the back of the file mark. The other refers to holding down the glass tube (rod), and the two hands are slightly forced to pull back at the same time.
Cutting of coarse glass tubes. The first will be cut off with a file to file a circle of fine marks, with resistance wire around the fine marks, resistance wire cross with heat-resistant insulation material separated (or leave 1mm-2mm small gap), resistance wire can be taken from 150W electric furnace wire one of the sections, heating straightening. The resistance wire can be adjusted to a very low voltage power supply by a voltage regulator or a low voltage power supply. Wait until the resistance wire is red hot for about one minute. Put a drop of cold water on the trace, and power off at the same time, and the glass tube will break along the trace.
The opening of the glass tube after disconnection is very sharp and easy to scratch the surface, so the glass should be treated after disconnection. The first method is that it can be put on the alcohol lamp to burn smooth; Second, it can be smoothed on a fine abrasive cloth or a grinding stone.