HOW TO CUT GLASS PROPERLY.

Wanganui Chronicle, Volume LXXIV, Issue 17640, 15 August 1919, Page 2

HOW TO CUT GLASS PROPERLY.

There is much loss in the course of * year through the breakage of glass. It is one of the serious " leaks" in the hardware business.

Sheet glass should always be cut on the hollow on- concave side. One can easily tell the concave side by holdiug the glass up and then glancing down the edge. Tlais slightly hollow 6r concave nature of Jjie glass is caused through the process of manufacture. In the manufacture of sheet glass it is first blown into cylindrical form that re. Kembles a huge bottle. This great bot-tle-like structure of glass, -which is from Id' to 20 feet in length and about 3 feot in diameter, is cut into section^ approximating 5 feet in length. These sections are split open at one point by drawing a hot iron across. They are then laid on a mould and flattened by means of heat from,a coke'furnace. It is never possible to make them exactly flat. The sheets aro slightly concave. There is greater resistance on the convex sido than on the concave side. This accounts for the cut "running out," and invariably a spoiled sheet if the cut is made along the convex side. But it is also very necessary that the cutting tool be kept in good condition. Care should bo taken that it does not get dull, or that the bearing in which it runs does not become worn. If the cutter becomes dull it will skip in places. Tlvjse little skips are danger places that often cause the cut to run out. If a wßoal cutter is used the little wheel should be kept oiled. When not in use if it be kept covered in coal oil it "will ulways be in good shape. As soon as it begins to show signs of dulness it should be discarded or the wheel should be replaced. Where a diamond is used it is always advisable for only one person to use the diamond. It is seldom that two people hold a glass-cutter in the same manner. Every clerk who is allowed to cut glass should have a cutter or diamond for his own personal use. And he should take good care of it. The breakage of two or three large lights of glass will cause a loss in actual money, equal to the cost of a good many glass-cutters. -- "Hardware and Metal.""