Making Holes in Glass

A visit to the local hardware store with chandelier light bulbs purchased at Dollar Tree and a hourglass plan raised some eyebrows among the staff. Eventually, after some brainstorming a purchase was made.  The plan was to rub the tip of the light bulb against a series of progressively very fine sandpapers: 220, 320, and 400 grit. Initially, double stick tape was put on a board and the pieces of the sandpapers were stuck onto it for stability.

The double-stick tape is put on the board, then pieces of
3 types of sandpaper stuck to it for a stable surface
to grind the light bulbs against.

The light bulb tip is rubbed on the
220 grit sandpaper in circular movements.

Eureka!  A simple way to make a hole in the tip that can be matched with a second one to make the hole for particles to pass through the center of hourglass.