Glass is a brittle and fragile material. With the right tool, however, machining does not cause any problems.
Cutting to size and replacing a damaged window pane is hardly a job for a silk maker these days. Because most windows today are provided with insulating glass, Replacements can only be made for them by a specialist. Inserting is easy, because most of these panes are only held in the frame by clamping profiles. However, glass is increasingly being used in furniture construction or for glazing pictures. And that's what cropping is for, Trimming or drilling is easy to do yourself with the right tools.
For smooth cuts
All flat glasses (with the exception of safety glass) can be processed with a glass cutter. These have tiny cutting wheels made of hard metal, which should only scratch the glass surface. You always need a stop for cutting, on which the tailor is guided. In the case of straight cuts, this can be a rail or a ruler with a non-slip underside, a stop with the corresponding radius for round cuts. Structured glasses are always scratched on their smooth side, Mirror on the uncoated front.
Tools for glass processing must be equipped with particularly hard cutting edges. Cutting here- and drilling tools. The glass cutter is guided vertically over the surface with medium pressure on the stop. For lubrication, immerse the cutter in water or turpentine beforehand. The recesses in the glass cutter are for breaking off narrow strips after scratching. Before doing this, tap the cut with the cutter from below. Broader strips are broken over a sharp edge. Also knock against the cut from below and then break abruptly with even pressure. Professional glass cutters are filled with cutting oil. The axis of the highly stressed cutting wheel is constantly supplied with the necessary lubricant via a wick. With a damp sanding sponge or a corundum stone (Tool whetstone) you can defuse the extremely dangerous edges of the cut surfaces.