Drilling Holes in Glass – Drilling a hole in glass sounds most difficult but it can be easily accomplished with a little care and patience.
Use either a hand drill, a bit and brace or a three-cornered file, similar to the type used for sharpening saws. Study the diagram and the process will be simple. Make a dam of putty round the place where the hole is to be drilled, about I in. in diameter and perhaps a ¼ in. deep as shown.
Fill this with turpentine. Place your drill over the hole to be cut and start drilling at an even speed, without much pressure on the glass. You will soon hear a grinding noise and know that all is well.
When the drill has penetrated through the glass, use the drill as a reamer, feeding it gently to enlarge the hole to the required size. Use plenty of turpentine so that the section is smooth and gentle.
Your glass will then be drilled quite cleanly and without any chips or cracks in the surface.