How to Drill a Large Hole in Wood

May 10, 2021

As a newbie woodworker, there will always be instances wherein you will need to cut precise and large-diameter holes in your woodworking projects, and doing so could be very challenging. Fortunately, projects like that seldom come by. But when such a project comes and requires you to cut a large circle, you don’t need to feel at a loss about how to do it. You only need to have the right tools to accomplish it and learn the “hows” of doing it.  

However, if you will only use a handheld drill instead of a drill press, you may end up having a hard time drilling precise holes. Handheld drills come with a smaller chuck of around ½.” Hence, you will only have a few twist bits to choose from if you use handheld drills. Moreover, it will be challenging to keep your drill at a precisely 90-degree angle relative to your workpiece if you use a handheld drill.

Drill Bit Types for Drilling Large Holes in Wood

As a newbie in woodworking, you will find it a no-brainer when choosing drill bits for drilling various types of small holes. But when it comes to large-diameter holes, you might get a bit confused as to which drill bit will be appropriate to use. Hence, if it is your first time drilling large-diameter holes, you might as well check out the following types of drill bits you can use to drill large holes:  

1) Forstner Bits

You can use the Forstner bits with a handheld drill. But you should ensure that your bit goes in square and straight using a light touch. Forstner bits, of course, can drill deep holes. Nevertheless, to get a straight and clean-sided hole, you need to draw out the bit more often to do away with chips and avoid overheating of the bit. 

Since cutting clean-sided holes let the steely bit in contact for a long time with the wood, it can generate too much friction, which may lead to overheating. Thus, if you heavily use your bits, you might as well spend on a carbide Forstner bit designed to bear enough heat without becoming dull. 

Investing in a Forstner bit kit will be a good idea if you are often engaged in cutting clean-sided holes. In this way, you will have an ample supply of variable bits to allow you to drill holes of varying sizes. 

The usual range of Forstner bits is from 3/8″ to around 1”. You can chance upon a Forstner bit with a 2” diameter in some instances, but more often, Forstner bits are only up to 3/8″ in diameter.

2) Circle Cutter

If you intend to cut holes that are larger than what a typical Forstner can manage, you should go for the circle cutter. The use of a circle cutter, however, necessitates a drill press. With the circle cutter, you can cut holes up to 6″ in diameter. The circle cutter also cuts smoother and cleaner holes. You can utilize it to cut tight openings for vac hoses, fences, jigs, and many others. You can also utilize the cut pieces to create toy wheels.

Furthermore, you can sharpen this cutter with ease. Moreover, when using a circle cutter, make sure that you set your drill at a low speed. Besides, you should clamp down your workpiece and take extra precautions to keep your fingers clear of the drill bit. Afterward, drill slowly and steadily.

3) Spade Drill Bits

If you are looking for a drill bit that can drill up to 1-1/2″ holes in diameter, you should check out the spade drill bit. Also called paddle bit, the spade bit features a flat and wide blade. Tradesmen like plumbers and electricians often use this bit to drill holes in walls for running pipes and wiring. Yet, even if tradesmen mostly use it, you can also use it in woodworking projects.

Spade bit’s flat and broad blade comes with a pilot point. This pilot point is attached to a quarter-inch shank that you can use in quick-chuck impact drivers and regularly-chucked drills. The bit’s flattened portion’s edges are sharpened, and the sharpened area’s bottom corners come with a pointed tip. 

The two sharpened bottom edges of the bit turn and dig into wood stock around the center point as it shaves wood like a corkscrew out of the hole. Moreover, it can produce very long shavings if its cutting edges are very sharp.

4) Hole Saws

Another excellent way to drill holes in wood is by using a hole saw. It can drill holes ranging from 5/8″ to 4-3/8.” The downside of using a hole saw is that it doesn’t cut as cleanly as a circle cutter. Nevertheless, it can create holes as big as those drilled by a circle cutter. 

You can use the hole saw with the handheld drill, and it is straightforward to use. The bits require high torque. It also needs a firm grip on the wood piece or material you would like to drill. You can use the hole saw to drill holes in materials as thick as two inches. 

The hole saw can come in handy if you don’t have a drill press. It is also handy if you are engaged in remodeling jobs that necessitate drilling big holes in lumber. Likewise, you can use it to drill holes in thin metal if your hole saw comes with a carbide or bi-metal teeth.

The downsides of using a hole saw, however, include its inability to drill at angles. It also requires extra work after you’ve already made a hole in the wood because you need to remove the plugged wood from your saw. You will find it challenging to remove the plug if the plug has already bound itself onto the saw’s head. 

On the plus side, the hole saw allows you to drill large holes several inches in diameter. Moreover, the hole saw requires less power, making it an energy-efficient alternative. Additionally, it is not messy because it doesn’t grind too much during the drilling process.

5) Auger Bits

Another option you have for drilling large-diameter holes using a handheld drill is the auger bit. However, the auger bit is best for drilling holes in wood with greater thickness. You can use the auger bit with a powerful drill. 

The auger bit can be challenging to handle and can create a rough hole behind it. It features a helical screw blade, and its rotation causes the drilled-out material to move out of the drilled hole.

6) Self-feed Drill Bit

If you are engaged in running wire and pipes through holes, you should consider using the self-feed drill bit. This drill bit features a tip that comes with an extended screw tip. This extended screw tip extends from the end of the bit, allowing it to sink itself into the spot as it feeds itself downward. 

Its wide annular ring will enable it to tear into the surface and efficiently create a deep hole. For this reason, this bit is increasingly becoming popular. 

Compared to the spade bit, the self-feed bit can be set to bore moderately in any thick workpiece. Some hole saws, of course, can drill deeper with a single pass. Nevertheless, you will find the self-feed bit easy to use if you can drill from both sides.  

Since self-feed bits can drill holes within the range of holes that hole saw and spade bits can drill, you may sometimes get confused about when to use it among these drill bits. You can use the self-feed bits if you want to power through the wood as quickly as possible, just like when you want to install under cabinet lighting and drill a hole for it. 

When it comes to precision drilling, of course, self-feed is not your best option. Precision drilling may necessitate the use of a drill press equipped with a Forstner bit. However, the self-feed bit is best for use by general contractors, plumbers, and remodelers.

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Factors to Consider When Choosing Bits for Drilling Large Holes

Since there are various types of bits to choose from when drilling holes, you should be very careful with your choice. It will be best to consider the following essential factors to zero in on the most appropriate bits for your needs:

Price

The larger the bit’s size, the more expensive it will be. Yet, the type of a bit will also dictate the price of the bit. Nevertheless, if budget is not an issue for you, you can always get the most appropriate bit to use even if it is expensive.

Size

The size of the bit will also be a factor in your choice of a bit. Thus, you should determine beforehand the diameter of the holes that you will drill. Knowing the range of the diameter that a bit type can drill, you can narrow down your choice to those bits that can create the holes within the range of diameter you intend to drill. 

Smoothness and Tear-out

Of course, it is also useful to consider the smoothness of the holes that you will make. If you are engaged in drilling holes on high-quality plywood for decoration, you would surely want to come up with smooth and splinter-free holes. Yet, if perfection isn’t an issue, you can always go for bits that can drill well without necessarily producing clean-sided holes.

Stopped Hole or Through Hole

It will be useful likewise to consider whether you want to make a stopped hole or a through-hole. Some bits can make a stopped hole that has a flat bottom. Others, however, cannot, but can only make through holes.

Angled Hole or Straight Hole

Some bits can’t drill angled holes. But some can drill accurate and clean angled holes. Besides, other bits may flex or break when pushed to drill angled holes. So, ensure that you only use bits that can drill angled holes when you want to make angled holes.

Drill Press or Handheld

Another factor you need to consider when drilling holes is whether you want to use a drill press or handheld drill. It will be helpful to remember that some bits can only be used with a drill press, while others can work well and safely operate using a handheld drill.

Deep Holes or Shallow Holes

It will be useful to note that some bits are excellent for drilling deep holes. Other bits, however, thrive in making shallow holes. 

Overlapping Holes or Not

You should also consider the bit’s ability to create overlapping holes sans wandering too much from the spot. Such a capability is crucial if you are drilling stopped holes for cleaning out a mortise.

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Conclusion

Given the varieties of bits in the market today for drilling holes, you will undoubtedly have many options when drilling holes on your workpiece. However, the essential factors mentioned above should dictate your choice of drill bits to facilitate your search process. It is useful as a newbie in woodworking to know your options at hand and the pros and cons concomitant with your option. In this way, you can easily zero in on the best bit to use for your woodworking projects.

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If Your Drill Bit Isn’t Long Enough, What Should You Do?

Depth is a crucial factor that may engender a problem when you are drilling large holes. With a short drill bit, of course, you will find it hard to drill up to the required depth. Nevertheless, you can always remedy this issue by knowing the following tips.

First, you should consider extending your drill bit. You can find extensions for drill bits, especially for bits used to bore large holes. Extensions are widely available for some drill bits like hole saws.

Yet, if an extension isn’t available for your drill bit, you must carefully plan how to drill through-holes. You can work, for example, on both sides of the work piece to complete a through-hole. You can start with an initial hole using a standard drill bit. You can then use this initial hole as your reference when drilling on either side of the wood.