How to Drill a Large Hole in Wood

A rare but important challenge for many homeowners is drilling a large hole in wood. Reasons for drilling large holes often begin with plumbing but drilling large holes is necessary for a wide range of home renovation projects. We can help you select the right tools and methods for drilling a large hole through wood.

Types of Large Holes You Can Drill

As surprising as it may sound, there are numerous types of holes to drill on wood. Understanding your project and its requirements is a vital step before you begin drilling. Some projects require counterbored holes, others can handle rough cuts, while others need stain-ready smoothness.

Counterboring Holes

A common type of large hole is a counterbored holes. Counterbored holes create a hole that extends partially into your wood without going all the way through.

These holes are often deep enough to contain a hex- or round-headed screw and a wood plug. Hole depth is determined by head height of your screw plus the plug depth. Wood plugs are often 3/8″. After installation, wood plugs will create a flush, wooden top.

Counterbored holes are also used to install many soft-close cabinet hinges and for cabinet pulls.

Plumbing Holes

Cutting through plywood or joists to run water drain lines or ventilation lines are common during home renovations. Dryer vents often require 4” holes, while plumbing can require anywhere from 4” to 1/2″ holes.

An easy way to spruce up a woodworking or hobby shop is to install a permanent vacuum. Creating ports as well as running and connecting vacuum lines to tools which produce sawdust often needs large holes.

Mortise Holes

One of the most common joints in woodworking is a mortise-and-tenon joint. This method joins two pieces of wood by creating a male end on one piece and a female piece on another.

The wood that will be the female piece will have a mortise hole, usually square or circular, cut into it. The male will be shaped, or be tenoned, to fit precisely into the female hole. Large mortises are a type of large hole that regularly needs to be cut in wood.

Holes in Furniture

Whether it is a butcher-block kitchen counter, a bathroom vanity, or an office desk, drilling large holes are often necessary in every room of the house.

Running water lines for a sink or creating an inconspicuous path for electrical cords, large holes can make your space look cleaner and more customized.

You might need to make a square hole in the wood.

How to Pick the Right Drill for Large Holes in Wood

There are numerous specialized tools out there to help you drill your large hole. Each has its optimal application.

Hole Saws

Hole saws come in many sizes ranging from as small as 1/4″ to industrial uses at 5’. Most readily available hole saws have a limited depth at 2”. 

Most hole saws also include arbors. Arbors are a drill bit that passes through the center of the hole saw. This allows users to more easily align their cuts by drilling into the dead center of your circle.

For hole saws to work well, the depth of the wood being cut should be less than the depth of the hole saw.

Forstner Bit

A Forstner drill bit with a high powered drill is one of the best tools for drilling a large hole in wood. However, this type of bit often carries a comparatively high price tag.

The Forstner bit excels at partial holes that do not pass completely through the wood and holes that require precise, flat-bottomed holes.

Spade Bit

The spade bit is the workhorse of hole-drilling bits. These bits, sometimes known as paddle bits, are for drilling holes completely through wood. Spade bits are great for drilling holes through 2x4s or 4x4s.

Self-feed Bit

Self-feed bits are a newer style of bit that combines the utility of spade bits and hole saws. The arbor, which helps to center the cut being cut, also features a screw design. This screw design pulls the bit into the wood.

The screw arbor leads to a spade bit which clears materials from the center of the cut. Surrounding the spade bit is a hole saw. These powerful combination bits are made to chew through wood quickly making it ideal for holes through standard dimension lumber.

Circle Cutter Bit

The final bit we think worth mentioning is a circle cutter. We recommend only using this bit with a drill press. Circle Cutter bits have a standard drill bit with a strong metal arm, and on that arm is an adjustable blade.

Circle cutter bits can methodically and precisely cut any size hole. Many drill bits for cutting large holes in wood come in 1/2″ increments. Circle cutters allow you to cut holes in nontraditional sizes but require a drill press to perform at its best.

How to Drill a Large Hole in Wood

Now that you know about the types of projects and drill bits, let’s walk through the steps of drilling a large hole through wood.

There are two tools we recommend to power your bits: power drill and drill press. Power drills are common handheld drills that are powered either through an electrical cord or a battery. Of late, even entry level cordless drills have a lot of power to drill through wood.

Drill presses are much larger and less common. However, even a lower priced drill press will make your drilling a lot more accurate.

Drill presses are usually immobile, permanently attached to a stand, and are mechanically raised and lowered. Raising and lowering the drill press in this way guarantees the drilled holes are completed at the proper angle. Drill presses also provide better control and visibility of cut depth.

Using a Power Drill to Create Your Large Hole

Select your bit to use with your power drill to cut your large hole.

• Forstner bit: Best for recessed hole 
• Spade or self-feeding bit: Best for quickly cutting a hole through wood where clean finish is less of a concern
• Hole Saw: best for middle ground between precision and speed

Prepare your work area. If possible, secure the wood to be drilled to a stable surface or between a pair of sawhorses. Make sure the space beneath the hole to be cut is clear and that the piece of wood is supported on both sides of the intended hole to prevent the wood from flexing.

1. Mark the dead center of the hole which you are drilling on your wood.
2. Put on safety glasses and hearing protection if necessary.
3. Drill a small pilot hole using a drill bit such as a 1/8″ drill bit.
4. Ensure that the drill is in high torque mode. Usually this is speed setting 1.
5. Holding the drill just above the pilot hole, correctly align the drill and drill bit with the wood. This is usually perpendicular at 90 degrees. 
6. Power the saw to full speed.
7. While firmly holding the power drill, slowly insert the arbor into the pilot hole and allow the bit to lightly engage with the wood.
8. While maintaining a firm grip and gentle pressure, allow the bit to cut into the wood to your desired depth.

Tip: Allow the bit to do the work. Do not strain to apply pressure to your power drill. Hold the drill steady so that your hole is straight.

Using a Drill Press to Create Your Large Hole

Drill presses allow for greater control and precision when drilling your large holes. To use the drill press to make a cut:

1. Install the correct bit into your drill press.
2. Mark the dead center of your hole to be drilled.
3. Secure your wood onto the drill press base plate, aligning the drill pit center with the dead center of your hole.
4. Put on eye and hearing protection if necessary.
5. With the drill bit above the wood, power on your drill press.
6. Slowly lower the bit into the wood, allowing it to cut to the desired depth.

Tip: To prevent tear out on precision cuts going entirely through the wood, drill a pilot hole through your work piece. You can also use a drill press vise for increased accuracy across a lot of drilling.

Use the drill press to cut 3/4 of the way through your piece, then flip the piece over to finish the last 1/4 of the cut.

Conclusion

Cutting a large hole through wood is all about considering your variables and finding the right drill bit for the job. Some jobs require less precision and can be done aggressively. Others need the correct bits, patience and exactness to achieve desirable outcomes.