Drilling Glass, 3

Drilling with a Flushing Head

A flushing head with a re-circulating pump will deliver water to the drill site through the core of the drill. These are supplied complete or as a fitting for an existing drill press. This is suitable for holes of 4mm and larger. Smaller core drills are impractical both because the glass is easily trapped in the drill and the wall thickness of the drill makes them almost solid anyway.

An additional requirement is to have a means to direct the water back to the reservoir.

Every diameter drill bit has an optimum drill speed. The smaller they are the faster the speed. Drill presses do tend to be on the slow side for glass drilling, but often have ways of altering the speed. So it takes a bit longer, but there are big advantages in other respects.

Don't push down any harder than you comfortably can with the tips of your fingers. Keep it steady. Listen for the sound of diamond grinding glass

If the core gets stuck in the bit, knock it out with some stiff wire or a nail. Be careful not to damage the edges of the drill bit. Always remove each core right after drilling. They are difficult to remove if there is more than one in the core of the bit.

For other tips on glass drilling see:


Keeping things wet
Using a drill press
Drilling with a Flushing Head
Avoiding chipping
Drilling holes with copper tube and grit
Drilling tools
Drilling glass without a drill press
Hole Placement
Drilling speeds for diamond bits in glass