There are a variety of tools that can be used to power glass drills.

Dremmel and Similar Craft Motors
These are light duty high-speed drills. The ones those with variable speed controls are especially useful.  They work best for small diameter holes. They must have the speed turned down for drilling.  [See Drilling Speeds for Diamond Drills]. These can be combined with a flexible drive shaft for lighter weight.

Drill Press
However, the most important thing to have when drilling glass is a drill press. Doing it by hand is very difficult and wears out diamond bits very fast.  Dremmel and others make drill presses for their tools.

Drilling Machines
Purpose made glass-drilling machines are important for larger holes and production work. Flushing head adapters are available from suppliers that will convert a standard drill press into a glass-drilling machine. These tend to be much slower than the Dremmel style motors, but are very steady. The important thing about these is that they use hollow core drill bits, allowing the water to be fed through the drill bit directly to the glass-drilling site.

Drill Bits
The other tool needed is drill bits. The recommended type depends on the size of hole to be drilled.

Small diameter holes, up to and including 3mm (3/16”) require solid bits. These can be spade (unusual) or solid diamond-tipped bits. A number of manufacturers make solid drill bits from 2-6mm (3/32-1/4”), and some (especially lapidary suppliers) make the very small diameter bits from less than 1mm to 2mm.

Larger diameter holes are best drilled with hollow core bits, as less glass needs to be removed to achieve the hole. These can be used with a flushing head or simply by directing water to the drill bit, with a dam to hold the water around the site.

The bits will last longer if you use a drill press. The press keeps the bit wobble to a minimum and maintains the vertical, both helping to reduce the wear on the bit.

Hollow Core Bits
Hollow core diamond bits are of two types:

One -where a heating process attaches the diamond - is called sintered in Europe and a number of other countries, but bonded in North America.

The second – where the diamond is bound to the metal with resins and other chemical attractions – is called bonded in Europe, but plated in North America.

Again the English language proves to be a dividing rather than a uniting force.

Bits of the first type are longer lasting and more expensive.  These can be dressed with an aluminium oxide dressing stick to maintain their effectiveness.

Bits of the second type wear quickly and should not be dressed.

In general a diamond core drill breaks out much less glass at the bottom of the hole than a solid drill bit.

Water Pump

A further tool that is useful to have is a re-circulating pump.  This can be a small fountain pump with a flexible spout to aim the water on the drilling site. A foot switch can control the water flow. A large tub is required to act as the catch basin for the water that comes off the drill and as the reservoir for the pump.

Of course, you can drill glass without purpose-made drill bits. 

See Drilling Glass With Copper Tube and Grit for the method.

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