September 28, 2022
Wood joinery is a wood joining technique that woodworker applied to install and join pieces of wood or lumber together. It is an essential part of the woodworking process in order to make great woodwork. There are different types of wood joinery out there.
The type of wood joint to use depends on the woodworking project you are working on. Remember, there are a dozen types of wood joinery that you can try, but knowing which one to use and when to use it is very crucial.
For your next project, here are some of the popular types that you can try. Again, pick the one that will suit your next project perfectly!
What is a Woodworking Joint?
The wood joint is useful in woodworking and is one of the rudimentary things you should learn to become a woodworker. Woodworking joints, of course, are the traditional ways of securing two wood pieces together. Of course, you can use adhesives instead of wood joints. However, an excellent wood joint can help make joints more secure.
Throughout the centuries, wood joints have been used to build structures and furniture without adhesives. Today, however, you will learn various wood joint types used for multiple joineries and purposes.
Different Types of Woodworking Joints & Its Uses/Applications
Woodworkers plan on what woodworking joints to use for their projects to ensure stability and toughness. The more complicated it is, the better for its durability. Let us look into the different types of woodworking joints from the most basic to the more complex.
1) Edge Joint
Edge Joint is the most fundamental wood joint you should learn in woodworking. It is a side grain to side grain joint, and the glue will hold well in this joint. This joint gets usually utilized to make larger panels out of narrow stocks. The edge joint is easy to make. All you need to do is cut two square and straight edges. Then, glue them together.
You can also hinge the joint and then cut both wood pieces simultaneously. This way, you can ensure that the angled cuts will get squared with each other. However, if you are joining longer workpieces, it will be best to use dowels or biscuits to ensure excellent joint alignment.
2) Dovetail Joint
Dovetail joints get usually typified as the quintessential example of fine woodworking. This joint gets utilized to join two ends of two wood pieces, especially when making boxes. You can also use this joint to make drawers. If you intend to make fine furniture, you should learn how to make dovetail joints.
A dovetail joint using your chisels and other tools has been done throughout the ages. Besides, hand-cut dovetails have been acclaimed as the hallmark of exceptional fine woodworking quality. But you can also use power tools like router and dovetail jigs to create this joint.
One discussion, however, about dovetail joints is about which you should cut first between the pins and tails. Of course, you can cut the tails or pins first, and it doesn’t matter which one is cut first, as long as it gets cut precisely.
You need to gain a lot of experience and improve your skills in cutting to actualize a dovetail joint. For beginners, it will be best to learn the two rudimentary variations of dovetail joints at the onset: through dovetail and half-lap dovetail.
The dovetail joint is reliable. It is solid and sturdy because of how the tails and pins get shaped. You will find it hard to pull it apart, while it is almost virtually impossible to pull apart when it gets glued.
3) Butt Joint
Butt joint means butting into two pieces of wood together. It is one of the easiest woodworking joints to try. It is easy to do, but it is a weak type of joint. To make it stronger, you need to add some reinforcement to the joint. It uses glue to join the woods together.
Of all the woodworking joints, the Butt Joint is the most basic and straightforward. One end of a piece of wood is butted against another end using mechanical fasteners. Due to its form (right angle or square depending on where you look at it), it is also considered one of the weakest joints in construction. Some would often use reinforcement to make it stronger. It has many uses, but woodworkers mostly used this joinery for platform framing, wall framing, or cabinet making.
Simple woodwork projects like hanging wall decors use this type. Do it if you are placing light objects on top of it though. You have to consider the type of glue to use as well. Don’t use this type of wood joint if you are making a book cabinet – it will easily give out.
4) Biscuit Joint
This type of joint is more reliable than the butt joint. It uses oval-shaped pieces of dried and compressed woods like beech. In this type, you use a biscuit-shaped wood to join two joints or matching mortises. The biscuit joint provides flexibility for the two mortises, yet the flexibility will depend on the glue-up.
To use a biscuit joint, you have to insert the biscuit joint on both mortises. The distance must be the same for both mortises, and you must mark it from the face of the woods. This is the crucial part. As for the width, you can just make necessary adjustments and move the alignment as needed.
Using a biscuit joint can mean imperfect alignment. This type of joint requires a lot of effort and work, as well. You have to keep on cutting the mortises so you can insert the biscuits perfectly.
5) Bridle Joint
For a strong joint, you can do a bridle joint. It follows the principle of the mortise and tenon joint, among the strongest joints in woodworking. Basically, you cut a tenon on the end of your first wood. Now you cut a mortise on the other wood. When you combine them together, it gives each other strong support.
This type of joint doesn’t require too much glue. Once connected, it will form a corner like the ones you see in upright rails or table legs that are made of wood or lumber. This type of joint is great because it creates very stable woodwork. It would be best if you used a mechanical pin or fastener to make the joint stronger.
There are different types of bridle joints, such as the T-bridle, where you have to attach wood to the middle part of another wood or lumber.
6) Birdsmouth Joint
This woodworking joint is mostly used in roof construction and referred to as the bird’s beak cut due to its small triangular shape. It is found on the bottom of the rafter and provides a smooth flat area which the rafter can rely on to attach itself to the wall top plate solidly.
On the triangular shape, the vertical cut attached to the exterior of the wall is called the “heel cut,” and the horizontal cut where the rafter lays upon is called the “seat cut.” Woodworkers follow a general rule, which is never cut more than 1/3 of the depth of the rafter when making a birdsmouth to sustain structural stability and integrity.
7) Cross Lap Joint
This joinery is also known as overlapping joints in which two long-grain wood faces are joined in the middle of the wood instead of having them together at the end. Each half of the two boards is removed, and they overlap at the cross-section. Each wood board has two shoulders and one cheek having the same measurement so they would fit perfectly when joined. It creates an illusion that two pieces of wood continuously slipped through one another magically. Some carpenters prefer to use this type of woodworking joint for internal cabinet framing, decks, boxes, and cross-bracing for houses or buildings.
8) Dado Joint
As a woodworker, I always consider this as one of the toughest woodworking joints and also one of the easiest to create. Some people call dado cut joint a housing or trench joint.
One piece of wood has a three-sided channel that was cut across the grain in which another piece of wood can fit into. It is mostly used in woodworking projects, including bookcases and cabinets where there are shelves that fit into one side of the board. They are also used as dividers or partitions in a drawer that provides sheer strength as the piece of wood is being held on three sides.
9) Finger Joint
A finger joint is a type of woodworking joinery, which is also known as a comb joint, and it is considered as one of the most popular joints used by carpenters. It is similar to that of a dovetail joint but with a slight difference. Instead of using angled pins, this joint uses square pins. While it also does not require the use of any mechanical fastener to join the pieces together, it relies heavily on glue to ensure it does not fall apart. It does not offer the same interlocking strength that the dovetail can provide.
It is sometimes confused with a box joint as it is similar, but the box joints are used primarily for box-like frames or box corner projects only. When one is to look into the joined workpiece, the cross-section is quite similar to interlocking fingers between two hands, hence the name.
10) Half Lap Joint
Woodworker would often resort to using the half-lap joint whenever they lack longer wood planks. While it is not as strong as the other woodworking joints, it is still popularly used by many as it is easy to create. Not all of those large beams you often see in house or building frames were made of just one long timber, but most likely, they were made of two or more connecting wood pieces.
It is the same as the cross lap joint, but instead of joining in the middle of the plank, it is done at the end of each piece. The wood pieces to be joined together should have the same measurement of thickness, so when half of the thickness is removed, they can fit perfectly together. They are mostly used for temporary projects as they can be easily assembled and dismantled. Instead of using screws or wood glue, nuts, and bolts are the go-to connecting tools to avoid damaging the wood pieces when they need to be separated. However, they can also be used for permanent woodworking projects such as cabinetry by reinforcing it with glue, dowels, or other fixed mechanical fasteners.
11) Knock-down Joints
These are also called knock-down fittings that are easy to put together using basic carpentry tools, including a screwdriver, hammer, and drill. This type of woodworking joint refers to the bracket you see mostly on cupboards, cabinets, worktops, and any flat pack furniture for easy storage and transport. It is an easy way of joining materials quickly without using either glue or clamps. This can be temporary, as it can easily be dismantled or fixed as permanent.
Here are some of the most popular knock-down joinery styles:
Two-Block Fitting, also known as Lok-Joints:
This uses bolts and pins to attach the bracket made of plastic to the wood. The bolt goes into the first hole of a piece and then into the thread of the second hole of another piece. When the bolt is screwed tightly, it pushes the two pieces together. The pins, on the other hand, helps in making sure that the Fitting does not twist. It can easily be dismantled if need be without damaging the material.
Plastic Corner Block:
It is also called Fixit Blocks, which is normally used on kitchen cabinets. The bracket or corner block is pressed on two wood pieces and attached through the use of screws. It can be permanently fixed into the wood but can also be dismantled by putting out the screw with a screwdriver.
This bracket or joint is made of plastic, and screws are used to attach it to the wood by passing through four holes. Those four screws will securely hold all sides at each corner. Just like the other two knock-down fittings, this one can also be used permanently without worrying about its durability, but it can also be removed easily when its purpose has been served.
12) Miter Joint
The best way to describe Miter Joint is to look at a frame of a painting. This joint is made of two wood pieces that are both cuts at the corners at a certain angle, mostly at 45-degree. When putting together, it forms a corner of the frame. It is similar to a butt joint but cut differently and has a stronger finish since there is a larger area for flue attachment.
Visually, it presents an aesthetically pleasing result, which is why it is used for framing paintings or photographs. It can also be used on the outside door corners as well as in decorative window frames. While it is stronger than butt joints, it is also considered a weak joint.
To counter this problem, woodworkers would use a thin slice of wood, which is called a spline, and it is inserted into a slot to strengthen the joint. The spline can either be perpendicular to the joined corners, or it runs the same length of both the joined wood pieces.
13) Mortise and Tenon Woodworking Joints
This woodworking joint is considered one of the toughest joints out there. The mortise and tenon joint has been used for many decades in joining two wooden pieces at a 90-degree angle. It is quite simple to make, and it involves inserting one end of the wood to a hole in another piece of wood. The tenon refers to the end of the first piece of wood. The mortise refers to the hole found in the second piece of wood. When done right, it fits perfectly and is incredibly strong, but this flush fitting design is quite difficult to master. Woodworkers would usually use glue to reinforce the joint.
14) Pocket-Hole Joinery
This woodworking joint is popular with woodworkers, most especially with furniture makers. It is also known as the pocket-screw joinery as it uses screws to join the wood pieces. It is quite similar to the basic Butt Joint but with Pocket Hole screws, which means drilling two holes using two different sized drill bits. It takes a bit of practice, and there are certain rules to follow to properly make one, which includes setting the correct pocket depth, using a corded drill instead of a cordless one as it bores a cleaner hole, and clearing the chips by stopping halfway down when drilling to lessen the friction. Check the pocket-hole screw guide chart to ensure you are using the appropriate screws to match the thickness of the material.
15) Rabbet Joint
One of the most common joints that can be found in the kitchen cabinets is the Rabbet Joint. Its name is taken from an old French word, “rabbat,” which means “a recess into a wall.” It is quite popular due to its easy construction as it can be cut by hand or a table saw.
Woodworkers also consider the joint to have a fairly strong quality as long as screws, nails, or even dowels are used to reinforce the glue that is used to attach the pieces. This woodworking joint is also often found in bookcases, door casings, and some window frames.
In the single rabbet joint, only one wood piece is rabbeted or cut, forming a recess, and the thickness of the mating piece should be proportional to the depth (step) of the wood that was cut out to make an accurate fit. The wood can be cut either way as the wood grain can appear on either end. In the double-rabbet joint, both mating wood pieces are cut or rabbeted with the depth and thickness of the cut matching or fitting well to make a flush fit.
16) Scarf Joints
Some refer to it as scarph joint, a type of woodworking joinery that uses a method of putting together the ends of two pieces when the wood is not large enough to provide the required length needed in your project. It is a means to elongate the wood by joining overlapping pieces of wood in the same direction of the grain using a flush fitting design.
There are several ways to construct scarf woodworking joints, and not all of them can offer sufficient strength. Woodworkers would use a plain scarf for decorative correction and reinforce the glue with nails, screws, or mechanical fasteners. Sanding it properly afterward is a required step to level the flat surfaces before coating it with paint. However, a more complex scarf joint is preferred for projects that need a higher degree of strength, particularly for those sections in a big construction project that are not in line with each other.
17) Tongue and Groove Joints
It is a simple wood joining method which consists of two planks of wood with one piece having a slot or groove cut along its edge to match the ridge or tongue on the other edge. With the right cut and appropriate thickness, the edge-to-edge joint will fit perfectly. In the past, it was often used on huge tabletops, flooring, and paneling. This was mostly used pre-plywood era although some woodworkers still use this method for those with higher-quality boards.
18) Coped Joint
One variation of the miter joint is the coped joint. Since most rooms’ corners do not meet at precisely ninety degrees, a coped joint has been devised to address this issue. Beneath the miter joint, the coped joint gets positioned. A coped joint has two wood pieces carved like jigsaw puzzle pieces. These two pieces form a custom-fit joint underneath the miter joint.
Coping is also typically used in other molding and fitting of skirtings in a room. It makes clean joints possible in intersections wherein walls are not squared.
Of course, the other method used for fitting moldings is via miter joint. But miter joints rely heavily on the knowledge of the precise angle between two walls. Coping, however, comes in handy for internal corners.
Frequently Asked Questions on Wood Joints
Aside from knowing the different woodworking joints you can learn and use in woodworking; it will also help if you are familiar with the following FAQs about wood joints, for they may also be the questions you have in mind:
What are the Strongest Types of Wood Joint?
The combination of mortise and tenons is considered the strongest wood joint type in woodworking. This combo has been perfected throughout the years, even if an adhesive is not used. Yet, this wood joint is further enhanced with glue and is almost impossible to pull apart.
What is the Weakest Types of Wood Joint?
The most straightforward joint is the butt joint. It is also often used and appears to be the weakest. This joint solely depends on the nails and adhesive to ensure it will not get pulled off. You can use this wood joint for simple projects, considering it is the weakest among wood joints.
What is the Most Common Wood Joint Type?
The butt joint, of course, is the most commonly used wood joint type worldwide. The reason is that it is simple to make and can be a bit reliable. Another common type of wood is mortise and tenon, which are also popular.
Woodworking is a serious business; it is not something you can just do on the spot without properly planning the execution. To ensure the stability and longevity of the end product, it is extremely important to know your woodworking options to be able to use the most appropriate one and to learn how to do the joint accurately and adequately. Keep in mind that the durability and strength of the whole structure would depend highly on the joinery technique that you used.
When working on any woodworking joint, it is important to remember the following pointers:
- Before making the joint, it is advisable to look into the other parts of the wooden construction. Take into consideration the load of the weight of the whole thing and the joint that should be used to fully support it. Clearly, the external weight can directly affect the effectivity of the woodworking joint.
- Never forget that the wood can easily contract or expand when there is a change in the surrounding climate.
- Do not only focus on the wood material and the type of woodworking joint you will apply, but take time to choose appropriate glue and mechanical fasteners to perfectly match each type of joint.
Jason is a 40-year-old woodworker, carpenter and author who have been involved in the woodworking and woodcraft industry with 17 years of experience. He is expertise in technical aspects, woodcraft and furniture building projects.