Whether you are an amateur woodworker or a seasoned woodworking veteran, you might be looking for the perfect type of wood joint for your latest project. You need something strong, but with so many types of joints out there, it can be tough to decide which direction to go.
While the dovetail, box (finger), and mortise and tenon joints are known to be the strongest type of wood joint, each is used for various purposes. For joining two panels, use a dovetail or box (finger) joint; for joining two posts, choose a mortise and tenon joint as the strongest, when applicable.
Of course, if you ask a skilled carpenter or woodworker what his or her preference for the strongest type of wood joint in his or her eyes is, you are likely going to find that they report what they use most commonly.
However, this does not make one inherently better than the other. You need to consider your furniture’s needs and how the design of the overall piece affects which type of wood joint will truly be the strongest to support the rest of the design. Let’s take a closer look.
What Types of Wood Joints are There?
If you are new to the woodworking realm, the number of different wood joint variations out there might seem a little bit intimidating at first. How do you learn how to apply them correctly?
To which pieces of furniture do certain types of wood joints apply? What tools do you need to make them work? How can you be confident that you chose the right type of wood joint for your unique project?
The questions can seem endless, and if you are starting from scratch and do not have anyone with who you can ask these questions, you might feel overwhelmed.
However, try to take a deep breath and realize that almost every woodworker who perfected his or her craft was right where you are now- to wonder the ins and outs of the trade and struggling to be confident in choosing something as insignificant (yet obviously important) as the type of wood joint to use on their project.
Fortunately, many skilled woodworkers and carpenters can participate in online forums, YouTube videos, and other means of communication to enlighten those of us who might be newer to the game.
Hopefully, you will have someone you can do an apprenticeship with- someone who can truly show you the rules of the road. If this is not an option for you, you will need to do some research independently.
One of the best places to start is looking at the various types of wood joints that even exist. With so many options to choose from, it is helpful to review a side-by-side list to feel that “ah, ha” moment when everything starts to click and your confidence in choosing the right type of wood joint sets in.
Three of the most important wood joints are the dovetail, box (finger), and mortise and tenon wood joint. These are the three strongest types of wood joints, but each is used for different projects- one working better for panels and another for posts, etc.
Other types of wood joints include dowel joints, miter joints, butt joints, lap joints, and tongue and groove joints. Of course, there are other types of joints out there, but these are among the most commonly used strong types of wood joints that you will find amateur and skilled woodworkers and carpenters alike using.
Strongest Types of Wood Joints
Dovetail joints are known to be one of the strongest types of wood joints. They are most commonly used for joining two panels of wood, but they can be used for other projects. A dovetail joint has interlocking sections that hold steady and secure because of their dovetail-shaped wedges that are put into place.
Particularly, dovetail joints are great to use with furniture pieces like drawers or anywhere that two wood panels meet at a perpendicular (90-degree) angle. Additionally, because the interlocking joint is made of the wood itself (both the pin and the opposing side), no additional hardware is required when using this type of wood joint.
Box (Finger) Joints
Box joints, otherwise known as finger joints, are another type of strong wood joint- known to be one of the strongest when it comes to interlocking two panels together. Similar to the dovetail joint, a box joint is used to interlock two pieces of wood together at a perpendicular (90-degree) angle, although it can be used straight on as well.
The box joint gets its other name (finger joint) as the wood sections that interlock mirror how your fingers interlock when clasping your hands together.
One piece of wood rests directly on top of the other, forming a strong interlocking section of wood with identical support segments. Some carpenters prefer box joints to dovetail joints because of their consistent 90-degree or 180-degree angles rather than the dovetail pin’s wedge angle.
Mortise and Tenon Joints
Mortise and tenon joints are the third of the most commonly reported strongest types of wood joints. However, mortise and tenon joints are quite different from the other two (dovetail and box joints) that more closely resemble one another.
A mortise and tenon joint is made to interlock two posts of wood ideally- a stronger solution compared to using this type of wood joint for adjoining two panels, although this is still possible, too.
This type of strong wood joint strengthens the wood that it is adjoining as a tenon (narrowly cut, specifically-shaped piece of wood) is inserted into a cavity (known as the mortise) on the other wood post.
When you think about it as an electric plug, the tenon is the “male” end, and the mortise is the “female” end of the joint that fastens two posts together. This is a strong type of wood joint that allows a secure positioning of two wood posts, but it is made for straight-on connection and requires precise cuts for the pieces to fit exactly together.
Other Types of Strong Wood Joints
Dowel joints are similar to mortise and tenon joints in that one piece (the dowel) is inserted into a precisely shaped cavity to fit the dowel on the adjoining piece of wood.
The difference between a dowel joint and a mortise and tenon joint is that a dowel joint uses an entirely separate piece of wood (the dowel) to connect the two panels or posts. In contrast, a mortise and tenon joint has the pin and cavity directly carved into adjoining wood pieces.
In this way, a similar type of joint is allowed to be created, but since the dowel is a separate piece, it can slightly weaken the wood joint compared to a mortise and tenon joint that has the entire cut directly linked.
However, one major benefit of a dowel joint is that the dowel can be placed securely on any portion of the wood that you are adjoining the other section.
Instead of being locked into securing the mortise and tenon joint where the two pieces meet, you can place a dowel anywhere on the woodworking piece you create and create a matching cavity to be placed securely on it.
A miter joint is most commonly seen on a picture frame or framework throughout your home. Typically, a 45-degree angle is cut on two pieces of wood, and they are placed together to match. Then, they are adjoined by another type of hardware or a strong adhesive.
The limit in a miter joint’s strength is that it relies on hardware or adhesive to secure it together, so if these lose their structure or strength, so does the entire woodworking piece. Still, this is a commonly used type of wood joint perfect for framework or other angled woodcuts.
Closely mirroring a miter joint, a butt joint uses the flat ends (butts) of wood to be joined together rather than relying on angled cuts to be securely adjoined.
A butt joint relies on exactly perpendicular cuts on wood that are then placed directly next to each other or perpendicular to one another to be secured by additional hardware or a strong wood adhesive. This type of wood joint is particularly popular with wood trim in your home.
Lap joints are another type of wood joint found in two main variations: full lap joints or notched lap joints.
A full lap joint would be one piece of wood placed directly on top of the other piece of wood and then secured with additional hardware. There is very minimal cutting or measuring required in this type of wood joint, considering it is placed on top of the other.
Alternatively, you can find a notched lap joint in which two pieces of wood overlap, but their ends have been precisely cut to hold and then be placed right on top of the other. This joint type still generally requires additional hardware or a strong wood adhesive to be secured.
Tongue and Groove Joints
Closely mirroring a notched lap joint, a tongue and groove joint has one piece of wood that overlaps the other (the tongue of one piece of wood resting on the groove of another piece of wood).
However, tongue and groove joints can differ from a notched lap joint in that the tongue and groove can be found on the entire edge of a piece of wood lengthwise, whereas a notched lap joint is only found at one end of the wood.
Sure, a tongue and groove joint can be found at the end of the piece of wood like that of a notched lap joint, but it is not required to be at the end.
Still, you will find a tongue and groove joint typically interlock with a “clicking” interlocking mechanism (like those on hardwood floors), or they can be more securely adjoined with additional hardware or a strong wood adhesive.