Can you drill granite and wow do you drill a hole in a granite countertop or tile?
Granite can be drilled with the right cutting tools. You probably know that regular wood or metal drill bits cannot penetrate stones. You should use either a diamond core bit (hole saw) or a carbide-tipped masonry drill bit for granite to create a hole in it.
Granite floors and countertops provide several benefits. The natural material is relatively durable, beautiful, and it comes in numerous finishes and colors. Although it is somewhat expensive to other alternatives, it remains a popular choice for high-end projects. So it is important that you use the right cutting tools when working with granite.
What Is the Best Drill Bit for Granite?
One of the reasons why granite is a luxury option is because of the challenges it presents during installation. The material tends to be relatively brittle despite its overall hardness. That means you need specialty bits and saws to cut granite tiles to the required size for flooring or a backsplash. When you install a counter, you’ll need a drill bit to power through the material to insert the fasteners.
If you use the wrong drill bit, two results happen: the granite cracks or the equipment gets ruined. That’s why you need the best drill bit for granite today if you’re working on a new installation or a remodeling project.
When you drill through granite, you need to use a carbide masonry bit or a diamond hole saw for the work. It has a different cutting tip than what you’d use for working with metal or wood.
You might have noticed that you noticed there are two different tip choices. Which one would you choose?
Diamond vs. Carbide Drill Bits
You can select a diamond bit or tungsten carbide bit for drilling into the granite. Both options are suitable, which means it is up to you to determine a choice preference.
Diamond core bits are significantly more expensive than carbide-tipped masonry bits. But, when you properly maintain and handle a diamond-coated drill bit for granite, you can achieve significant cost savings over a carbide product. The usage ratio for diamond vs. carbide drill bits can sometimes be as high as 300-to-1.
Even when you use diamond drill bits on granite, you’ll find that most items can last about 25 times longer than a carbide product under the same conditions. It is important to know that the diamond bits will not work on soft materials such as wood, MDF, plastic, etc.
Tungsten carbide drill bits also can cut through granite although not as efficient as diamond-coated ones. The primary differences involve price and durability.
You may go through more than one carbide-coated drill bit when installing granite materials at home. Even if you go through 2-3 of them, it might be cheaper to use this method instead of buying a diamond-coated alternative.
If you decide to invest in a diamond-coated drill bit, you’ll want to review these facts before selecting the equipment for your project.
- Amorphous diamond is a carbon film that gets applied using vapor disposition. It is not as thick as CVD diamond coatings, which is a pure diamond product that uses chemical-based vapor disposition.
- If you plan to work with hardened steel after your granite installation, diamond tools will not work.
- You cannot guarantee that a recoated or re-sharpened diamond-coated tool will function as well as it did straight from the package.
- The life of a diamond-coated tool is not warrantied against what a carbide alternative might offer. You might only get up to ten times the life of the product, reducing the benefits of the extra investment.
In short, use diamond core bits for granite countertops, tiles and thin sections. Use carbide-tipped masonry bits for granite rocks, large stones and thick sections.
What Drill Type Works Best for Granite Surfaces?
When you need to drill through granite, you need the power to push that diamond or carbide drill bit into the material. If you have the right combination of power tool and drill bit, it should take you about 60 seconds to create a pilot hole for your installation. When you need to create an installation point for a faucet, dispenser, or another countertop addition, a larger bit might take up to 120 seconds to work through the material. Anything that takes longer than that indicates you don’t have the correct drill bit or enough power to get the job done.
You probably have seen conflicting info on the type of drills that you should use when drilling granite. Let’s clear the confusion today.
Drilling Granite: Hammer Drill or Regular Drill?
If you use a hammer drill to drill thin granite sections, the pulsating action you receive while pressing into the material can result in developing cracks. This is especially important when using heavy-duty rotary hammers on thin granite tiles. Here the best practice is to use a diamond core drill bit on a regular drill.
If you have a thick granite slab to manage, a corded hammer drill or rotary hammer is the better choice to use. The extra power received from the receptacle can let you keep moving with consistency.
- Thin Granite Tiles and Countertops: Use diamond core bits and standard drill without hammering action
- Thick Granite Slabs: Use carbide masonry bit on an SDS drill such as a rotary hammer or combination hammer.
Granite Drilling Tips
The best way to drill through granite is to use a steady, constant speed. If you pulsate to high RPMs to get through tough spots, you can create burn marks in the material, may cause the drill bit to stick, or ruin your equipment.
Here are some additional tips to help you finish your granite project quickly and effectively.
1. Put on Your PPE
Before you start drilling into granite, you’ll need some personal protective equipment to keep yourself safe. It helps to have safety goggles, a dust mask, and gloves to prevent an injury. Since you’re gathering supplies, you may want a marking tool and a water spray bottle available to complete the following steps.
A measuring tape allows you to know where each hole needs to get drilled.
2. Lay Down Some Tape
After you measure the granite to see where each hole needs to get drilled, lay some duct or masking tape along the path of your cut lines. The tape gives the drill bit some traction while you push into the material.
These lines should be at least one inch from the edge of your granite surface to avoid the risk of cracking. This is called the minimum edge distance.
It works better to complete all of your measurements first so that your cutting work can happen in one step. Outline your sink area, fixtures, and other places where modifications are necessary.
3. Affix Scrap Stone to the Bottom
Granite is hard and wear-resistant, but the material can also be exceptionally brittle at its edges and endpoints. When you start drilling through it, the bottom of your hole can end up exploding out with shards because of this tendency.
You can avoid this issue by installing a piece of scrap stone underneath the drill point. By pushing the bit into the secondary material, you’ll create a cleaner cut from top to bottom.
4. Start the Drilling Process
After installing your preferred drill bit for granite, you’re ready to start the process. It helps to proceed at a slight angle as the equipment penetrates the material’s surface. Once you get a footing to use, gradually straighten the drill.
You’ll need to apply light pressure to the equipment to encourage it to push downward. It helps to let the bit do most of the work so that you get a clean cut.
Depending on the equipment you’re using, it is helpful to spray the area with water once you get downward movement to cool the cutting edge, encourage lubrication, and less dust. Please be careful if you take this step with a corded drill, as this action increases your electrocution risk.
5. Test Piece
If you’ve never tried to drill through granite before, it might be helpful to practice on a scrap piece first. This material is not forgiving, and any mistakes you make will have a permanent home on your installation.
Conclusion:
Most installers prefer a diamond bit for drilling through granite because of its overall consistency and durability.
Although carbide-tipped masonry bits are useful, they may not have a long enough lifespan for multiple holes.
Dan Miller is a professional toolmaker with extensive experience in the metalworking and tooling industry.
An avid DIY enthusiast and passionate hobbyist woodworker, Dan shares his expert knowledge here.