How to Drill a Hole in a Granite Countertop

Drilling through granite can be a very trying task to say the least if you don't have the right tools. Like with any job you need to know what you are doing.

If you watch the pros, they make it look so easy and effortless. That's because they do it everyday and have the right equipment. But, you can do it also with the right tools.

After doing some extensive research, this is what I've learned about drilling holes in granite counter tops.

You'll need to purchase a bit called a DRB01375, made by Alpha. This is what the guys who do granite fabrication are using. It is advertised as a bit that you can use wet or dry and will cut through a 3/4 slab in less than 30 seconds. They run them on angle grinders or use an adapter that comes with them and run them on any drill or high speed grinder.

It comes in sizes of 1/2", 3/4", 1”, 1-1/4", 1-3/8", 1-1/2" and 2".

Not only is this a very convenient drill bit but it also increases productivity by cutting down on the amount of clean up needed when using water. This bit does not need to be used with water. If dust is a problem, simply use a shop vac to suck up dust as you drill.

There are some cheaper models out there that are not nearly as effective and will not perform like the higher priced version. So go ahead and spend the extra money and save yourself the time and anguish of dealing with inferior products.

Attach the Alpha Dry Core Bit onto your high-speed angle grinder (or drill with adapter) by threading it onto the 5/8”-11 spindle.

Mark the location of holes that need to be drilled.

Use a template as a guide on the stone in order to avoid any mistakes during the drilling process.

Clamp a piece of stone scrap under the stone being core drilled to prevent excessive chipping or “blowout” on the back side of the stone.

Proceed with drilling, pressing steadily until the dry core bit drills through the stone.

When you are drilling multiple holes, you will need to cool off the dry core bit by dipping it in cool water after each hole is drilled.

While there are thousands of articles online about how to drill granite, the consensus on all of them that I found is to go the high speed route. Some say low speed and some say high speed. But if you use the drill bit suggested in the resources below it suggests that the high speed method is the best.

Resources:

Ace Tool

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