Wood Joints: Rabbet vs Dado vs Groove

While veteran woodworkers will be intimately familiar with wood joints, the vast majority of people who are just starting out in woodworking probably don’t know about the various kinds of wood joints and what each does. If you are an amateur DIYer looking to dive into woodworking as a hobby, then you need to learn about the various types of wood joints. In this article, I’m going to introduce you to three of the most common woodworking joints. I’m going to explain exactly what each kind of wood joint is, what projects they are used for, and finally, I’m going to explain how exactly each joint is made.

Difference between Rabbet vs Dado vs Groove Joints

What’s the difference between a dado and rabbet?

The main difference between a dado and a rabbet is that the dado is a slot cut across the grain of the wood in the middle of the wood stock whereas the rabbet is a step milled at the end of the stock to create a rabbet joint. A dado joint which has support on either side is stronger than the rabbet joint. The following picture illustrate the difference between the two joints clearly.

Now, let’s take look at each of these wood joints in detail.

Dados

What is a Dado Joint?

Dados (also often referred to as trenches in the UK and Europe) are slots that are cut into wood across the grain. A Dado joint is made by cutting a piece out of the face of the wood. While there is plenty of variation between projects, on average a dado joint will end up being roughly 1/3^rd of the thickness of the wood.

Dado joints can be difficult to master without the right tools. On the one hand, you want to cut enough out of the wood to make sure that the dado is deep enough to support whatever it is that you are putting in there. On the other hand, you don’t want to cut too deep, as you risk damaging the structural integrity of the wood and ruining its ability to support anything.

What is a Dado used for?

As one of the most basic wood joint, dado joints are used in a variety of projects, with the most notable example being bookcases. Dado joints are used to affix the shelves on bookcases to the larger piece of wood (also called the carcass). It’s also used in most kinds of furniture and cabinetry.

Are dado joints strong?

The dado joints are extremely strong and able to support lots of weight, which makes them ideal for things like furniture and shelving. You can add glue to the joint to position it accurately and make the joint more reliable.

How to make Dado Joints?

Dado joints can be made using either handheld power tools (especially routers) or using traditional power saws (like a table saw). Milling a dado joint with a handheld tool like a router is simple and relatively straightforward. Making it with a table saw is can be a bit trickier, but still very doable for an experienced woodworker.

Most well-known tool manufacturers sell specialty dado blades that can make the process much easier. For example, DeWalt sells a special “Dado set” blades for table saws. In general, cutting a dado joint using a table saw involves lowering the blade to the required depth and making judicious use of the table saw’s fence to guide the wood.

Other types of power saws that you can use to cut a dado joint are the Radial Arm Saw and the Sliding compound miter saw. However, Miter saw when compared to the table saw, is less suitable for wider work-piece.

How deep should you cut a dado?

The ideal depth of a dado is 1/3^rd of the wood stock thickness. You can go deeper, but not more than 50% of the thickness of your work-piece. This will reduce the strength of your work.

You should also consider using stopped dadoes to improve the strength and appearance.

Will a dado blade fit any table saw?

If you are using a stacked dado blade set, make sure that the arbor has sufficient length to accommodate the blade stack. In EU countries and the UK, the use of a dado blade is illegal. This is because to use the dado blade set on a table saw, you need to remove the blade guard which is a serious safety concern on the table saw.

Grooves

There is only one thing that sets grooves apart from dado joints. Dado joints are made by cutting across the grain of the wood. Grooves, on the other hand, are made by cutting along (parallel) to the grain of the wood. A groove can be cut on the face of your wood board or at the side depending on the purpose.

They are used for the similar assembly like dadoes and they are cut the same way as well.

How do you make a groove?

You make grooves essentially the same way as dados; either using a dado blade on a table saw or with a router.

Uses: Tongue and Groove Joints

A groove is half the component in a tongue and groove joint. The part of the joint that protrudes outwards is called the “tongue.”

The tongue and groove joint is mainly used for joining similar sized wood boards to create a large panel. For example the large wooden table top of your dining table table is probably not made out of a single piece of wood. They are assembled by using the tongue and groove joint technique.

Rabbets

What is a Rabbet Joint?

So, we covered how dado joints and grooves are basically slots cut into the wood. Well, rabbet joints are bit different. Rabbet joints are essentially recess or steps cut into the side of the wood, as opposed to directly in the middle of the wood. You can cut rabbet across the grain or along the grain depending upon the requirement.

If you are having trouble imagining what a rabbet joint looks like, think of it this way; A rabbet joint, when viewed from the side, essentially looks like a small set of steps. Below image illustrate a rabbet cut.

Rabbets can be milled along the grain and across the grain as well as on the side and face of the board.

What are the uses of Rabbet Joints?

Rabbets generally are used in smaller woodworking projects, like building drawers, small cabinets, desk drawers, and even things like picture frames. They lack the ability to be used in bigger projects like bookshelves or furniture. Certain kinds of specialty furniture can be made using rabbet joints, but they are rare. In some projects, you may even be required to combine dado and rabbet joints together.

Take a look at above image. The double rabbet provides additional strength by resting on the shoulders.

How to make them?

Rabbet joints can be made using a variety of tools. One can easily make them by using a standard table saw. However, they can also be made using a radial arm saw or a sliding compound miter saw.

Finally, you can also mill them by using a router (either a table model or a handheld one, it doesn’t matter), the same tool that you use to make dado joints.

Conclusion

Obviously, this article only scratches the surface when it comes to woodworking joints. To list and explain all the various woodworking joints in any detail would require several articles. This article was simply intended to act as an introductory article and to explain the difference between the three basic woodworking joints that every woodworker has to be familiar with.