A guide to specialty drilling:
the right bit makes the difference

A chipped tile or cracked piece of glass can turn a straightforward drilling job into a costly rework. The challenge is knowing what bit to use, how much pressure to apply and whether the job needs water for cooling.

The right setup gives you more control and helps protect the surface as you drill. It can also reduce heat, unnecessary bit wear and the risk of having to do the job all over again.

This guide explains which drill bits suit common speciality materials and the techniques that can help you achieve a cleaner result.

A guide to speciality drilling

Which Drill Bit for Which Material?

Use this quick guide as a starting point, then always check the product instructions before drilling.

Material or

application

Porcelain and hard tiles

Granite, marble, limestone, slate and travertine

Ceramic tiles and non-toughened glass

Dry drilling in compatible material

Larger diameter wet-cut holes

Recommended

Alpha bit

Alpha Diamond Max Core Drill Hex Shank

Alpha Spearpoint Drill Bit

Alpha Wax-Filled Diamond Core Bit

Alpha Spearpoint Drill Bit

Technique tip

Use the recommended speed, avoid excessive pressure and manage heat throughout the cut.

Let the diamond tip cut without applying excessive pressure.

Use low speed, light pressure and water for cooling.

Follow the dry drilling instructions and recommended speed on the packaging for the selected bit.

These specific larger bits are not wax-filled, so water is required during drilling. Follow the instructions for the selected size.

Drilling Porcelain, Ceramic and Stone

Hard materials such as porcelain, granite and marble can be demanding to drill. A standard drill bit may struggle to break through the surface, build up excessive heat or wear prematurely.

The Alpha Diamond Max Core Drill bits are designed for wet or dry drilling through materials including porcelain, ceramic, granite, marble, limestone, slate, terracotta, fibreglass, travertine and masonry.

They perform in heavy-duty commercial tiles and are more suited to harder materials, with the diamond segment tip helping to manage temperatures and provide a long working life.

The diamond segment tip is designed to help manage cutting temperatures. Its wide-slotted design also improves visibility while drilling and assists with plug removal.

FOR THE BEST RESULT

Avoid trying to force the bit through the material. Use steady pressure, keep the drill under control and follow the recommended cooling method. The diamond composite technology also allows the bit to be dressed in line with the product instructions, helping to maintain its cutting performance.

The Alpha Diamond Max Core Drill Bit

Drilling Glass and Tile

For jobs involving materials like subway tiles, laundry tiles, bathroom wall tiles or plate glass, a controlled drilling technique is important. These brittle materials can chip or crack if too much speed or pressure is applied. Always confirm that glass is suitable for drilling before starting, as toughened glass cannot be drilled after the toughening process. Alpha Spearpoint Drill Bits are designed specifically for these materials, with the tungsten carbide tip providing controlled and precise cutting.

FOR THE BEST RESULT

Use a slow speed, apply only light pressure, and keep the area cool with water whenever possible. Allow the drill bit to progress gradually through the surface; this helps control heat and minimises the chance of chips or cracks.

The Alpha Spearpoint Drill Bit

When wet drilling is not practical

Water helps cool and lubricate a drill bit when working with hard materials, but wet drilling is not always suitable for every job. Alpha Wax-Filled Diamond Core Bits are designed for dry drilling applications where an external water supply is not practical, with the internal wax assisting with cooling and lubrication during drilling.

A vacuum-brazed, diamond-coated tip helps manage cutting temperatures and is perfect for drilling porcelain, ceramic, granite, marble, limestone, slate, terracotta, fibreglass, travertine and masonry.

FOR THE BEST RESULT

Larger wet-cut sizes are also available in the Alpha Diamond Core Bit range. Unlike the wax-filled bits, these products require water during drilling, so always check the instructions for the selected bit before use.

The Alpha Wax-Filled Diamond Core Bit

5 tips for successful specialty drilling

1. Check your setup

Before you start, check exactly what you’re drilling, match the bit to the material, note the recommended drilling speed and confirm whether water is required. A few extra minutes on setup can protect the finish, extend the working life and keep your job on track.

2. Slow down and maintain control

Start slowly and follow the recommended speed for the bit and material. This gives the cutting edge time to work and helps you stay in control.

3. Let the bit do the cutting

Excessive pressure creates more heat and increases the risk of damaging the surface or wearing the bit prematurely. Apply steady, controlled pressure instead of forcing the drill, as this can lead to chips, cracks or unnecessary wear.

4. Manage heat throughout

Heat matters, especially when using diamond tooling. Where water is recommended, keep the bit adequately cooled throughout the cut.

If wet drilling is not practical, choose a bit specifically designed for dry use. Do not use a standard wet drilling bit without water unless the product instructions confirm that it is suitable.

5. Switch off hammer mode

Do not use hammer mode when drilling porcelain, tile or glass. The impact action can damage brittle surfaces and increase the risk of chipping or cracking.

Only use hammer mode when the selected drill bit, material and product instructions specifically call for it.

Match the Bit, Technique and Speed

Specialty drilling is not just about having the right tool. It is about matching the bit, technique and speed to the material you are working with.

Alpha’s specialty drilling range gives you options for hard stone, brittle tiles, plate glass, wet drilling and selected dry drilling applications. Match the product to the job, follow the recommended technique and keep heat under control.

That preparation can help deliver cleaner results, protect expensive surfaces and get the job done right the first time.

See our Specialty Drilling Range