How to Drill Granite & Stone: Best Drill Bits & Hole Saws for Countertops

Working with materials such as granite and stone has a few unique challenges. The density and brittle nature of these materials require the use of specialized tools and techniques. You are likely going to damage the materials if you try drilling using regular drill bits, causing a lot of frustration.

In this guide, we will look at the most professional way of drilling into granite tile countertops and other stone surfaces. Additionally, we’ll cover the best granite drill bits, diamond hole saws, and give you a step-by-step guide on how to prevent common mistakes when drilling.

What You Need to Drill Into Granite & Stone

Drilling into natural stone and granite starts by choosing the right power drill for the job. Drills are different, and choosing the wrong one can damage the stone surface or cause severe safety hazards. Here’s a breakdown of drill types and how they are suited for each job.

Choosing the Right Drill for Granite & Stone

Standard Drill (Not Recommended)

Most households have standard drills, but they are not powerful enough to drill into granite and natural stone. They are designed for softer surfaces such as wood and light metals. If you use a standard drill on granite, the drill bit will skate across without any progress. It may damage the material and the drill bit itself.

Hammer Drill (Use with Caution)

Hammer drills can handle tough materials like concrete, but should always be used with caution. They combine rotary motion with the hammering action for the best results. Yes, they can penetrate stone, but they are too rough on granite.

If not used carefully, they can crack stone or granite surfaces. When using this drill, make sure the hammering feature is disengaged and relies only on the rotary action. It’s a more controlled process to avoid frustrations.

Rotary Drill (Best Choice)

A rotary drill is the best choice if you want to get precise and clean holes in stone. It has consistent torque and variable speed control, allowing careful application of pressure. This design feature comes in handy when using specialized drill bits such as diamond core bits and diamond hole saws. These are necessary to cut into granite and other hard surfaces effectively. The most recommended product is the DeWalt DWE1622K Rotary Drill.

Angle Grinder with Diamond Bit

Angle grinders with diamond cutting discs are designed for cutting and shaping stone slabs. They can be used to create openings and modify edges, but they are not ideal for drilling holes. You may use an angle grinder for drilling holes, but you need to be highly skilled. The most popular and effective angle grinder when working with stone is the Makita 4.5-Inch Angle Grinder.

Choosing the Best Drill Bits for Granite & Stone

Carbide-Tipped Masonry Bit

Carbide-tipped masonry bits are designed for drilling into stone. However, they are more suitable for softer stone varieties such as sandstone and limestone. When it comes to granite, these bits don’t have the necessary cutting power. They are likely going to become dull or damaged, even worse, damage the material.

Diamond-Tipped Drill Bit

When creating small holes in granite, marble, or quartz, diamond-tipped drill bits are a good choice. The bits are embedded with industrial diamond particles to provide the toughness needed to drill through hard materials. They are useful when it comes to drilling pilot holes, creating mounting holes for bolts, or for small fixtures. The top recommended product is Bosch Diamond Tip Drill Bit.

Diamond Core Hole Saw

If you are drilling larger diameter holes in granite countertops, you must use a diamond core hole saw. It comes with a cylindrical design with a diamond-coated cutting edge. It can cut a circular hole and leave a proper solid core. The top recommended product is the Hilti 2-inch Diamond Core Bit.

Best Granite Drill Bits & Hole Saws

When handling various drilling tasks in granite, there are a few top-rated options to consider. For instance, the Bosch 3/8″ Diamond Drill Bit is perfect when creating small and precise holes. When cutting larger openings, the SHDIATOOL Diamond Hole Saw is the top recommended product.

On the other hand, for professional construction or more demanding countertops and other drilling projects, the Hilti DD-BI 4-Inch Diamond Core Bit guarantees top performance and durability.

How to Drill into Granite & Stone (Step-by-Step Guide)

You need to use a careful and methodical approach when drilling into granite and stone, unlike ceramic tile or porcelain tile. You must use the right tools and precise techniques to ensure clean and accurate holes. This is the best way to avoid chipping or cracking of the material. Let’s break down the essential steps below.

Step 1: Gather Your Tools and Safety Gear

Before you begin drilling in any room in your house, you must have the necessary tools and protective equipment. These include: a rotary drill, drill bits, a diamond-tipped small bit, a diamond core hole saw, a reliable water source, sturdy clamps, safety glasses, and dust masks.

Step 2: Mark the Drilling Spot & Secure the Countertop

Start by identifying the exact area where you want to drill the hole. Use painter’s tape on the stone surface to avoid chipping around the edges. Use a pencil or marker to mark the center of the desired hole on the painter’s tape.

Once you have marked the location, make sure the countertop or stone is fastened securely using the clamps. It’s the best way to avoid any movement during the drilling process, resulting in inaccurate drilling or damage to the material.

Step 3: Start Drilling at Low Speed

Make sure your drill is fitted with the right drill bit, then position it over the marked area. It should be at a perfect 90-degree angle to the stone surface. You can begin drilling at a slow rate and apply light pressure initially. At this stage, your goal is to create a small indentation to guide the drill bit and avoid wandering. Apply water continuously or coolant to reduce heat and remove the debris.

Note that when drilling a larger hole, especially when using a diamond hole saw, start with a smaller pilot hole. This will improve overall accuracy and prevent the larger drill bit from wobbling and wandering.

Step 4: Use a Diamond Hole Saw for Large Holes

If your project needs a larger hole, you must attach the diamond hole saw to the drill. Hold the drill steady and perpendicular to the stone surface. Drill at a slow speed and ensure stability to prevent the hole from wobbling and causing cracks. You can increase the speed gradually as you add water to the cutting area. The water is a coolant and lubricant, thereby reducing friction and overheating.

When using a diamond hole saw, you must take breaks every 20 to 30 seconds to allow the drill bit to cool down. It’s the best way to prolong the life of the bit and prevent heat-related damage to the material.

Step 5: Finish the Hole & Smooth the Edges

When the granite or stone is already drilled through, pull the drill bit out of the hole slowly. The newly drilled opening might have a little bit of a rough wall. In order to attain a perfect finish of the hole, you can either use a polishing pad that is the right size for the stone or a sanding disc with the finest grade available. Remove any sharp or raised edges delicately.

Common Problems & How to Avoid Them

Even with the right tools and techniques, you may encounter some common problems. Let’s look at them and how to solve them effortlessly.

1. Why is my granite cracking while drilling?

Your material will crack when drilling if you are using excessive pressure, if there is no support to prevent vibration, or if there is heat buildup. To prevent this, you must apply light and consistent pressure. The granite must be firmly clamped to prevent movement.

Keep a constant flow of water to cool down the drill bit and the stone surface. The painter’s tape around the drilling area will also reduce chipping.

2. Why is my drill bit overheating?

If your drill bits are becoming dull, they are likely going to overheat and may lead to cracking of the material. The best way to avoid this is by reducing the drilling speed and using enough water as a coolant. Take short breaks every 20 to 30 seconds to allow the drill bit and the material to cool down.

3. What happens if my drilled hole is not clean or smooth?

If you want to avoid a jagged or uneven hole, you must start with a small bit to create a pilot hole. Next, you can move on to the diamond hole saw to create a larger hole. It acts as a guide to the larger bit, thereby creating a cleaner cut. You must also maintain consistent and steady pressure when drilling.

4. What if my drill bit isn’t cutting?

If you are not making any progress with your drill bit, it’s because you may be using the wrong type. For granite and stone, you must use diamond-tipped drill bits. Carbide-tipped masonry bits are not hard enough. When drilling larger holes, you must use diamond core hole saws and diamond small bits for smaller holes. Don’t forget to check if the drill bit is worn out and needs replacement.

Best Drill Bits & Hole Saws for Granite & Stone

Top-Rated Granite & Stone Drill Bits

When creating small holes in granite, the top recommended product is the Bosch 3/8″ Diamond Drill Bit. If you need to cut out sink and faucet openings in granite countertops, the best product for the job is the SHDIATOOL Diamond Hole Saw. Finally, if you need the best tool for cutting larger holes in tough stone, the Hilti DD-BI 4-Inch Diamond Core Bit is an excellent choice.

Top-Rated Drills for Granite & Countertops

The DeWalt DWE1622K Rotary Drill is the top recommended product for precise drilling into granite and stone. If you are cutting through stone slabs, the Makita 4.5-Inch Angle Grinder is the right tool for the job. When drilling large-diameter holes, especially in a professional setting, the Hilti DD 150-U Core Drill is a great choice.

Conclusion

Learning how to drill into granite and stone requires expertise and professional knowledge. For clean and accurate holes, you must choose a rotary drill with a diamond tip or a diamond hole saw. When drilling, you must maintain a low speed and apply water consistently to avoid overheating and damage to the material. Choose the best tools and top-rated granite drill bits and hole saws today for the best results.

Working with materials such as granite and stone has a few unique challenges. The density and brittle nature of these materials require the use of specialized tools and techniques. You are likely going to damage the materials if you try drilling using regular drill bits, causing a lot of frustration. In this guide, we will look at the most professional way of drilling into granite tile countertops and other stone surfaces. Additionally, we’ll cover the best granite drill bits, diamond hole saws, and give you a step-by-step guide on how to prevent common mistakes when drilling.