Guide on Cutting Tenons on Table Saw

June 27, 2022

You may not believe it, but the use of mortise and tenon joinery dates back 7,000 years ago with the discovery of intact wooden furniture near Leipzig. This old furniture exhibited the use of mortise and tenon joinery, revealing that the ancient woodworkers had knowledge of this type of joiner and had been employing it to join wood.  

As a modern woodworker, however, it will help if you learn tenoning. Of course, cutting perfect tenons is a skill that you can’t quickly learn. It requires apprenticeship under a watchful eye of a master craftsman. Tenons and mortises are relatively easy to make with the right equipment and tools. But if you are using a table saw, you will, at the onset, find it challenging to make accurate tenons. Thus, before you even try to cut tenons using the table saw, it will be best to learn the proper techniques to do it right.

What Would You Need to Cut Tenons Using a Table Saw?

Before you start a tenoning project, it will be best to figure out how you would cut the tenons and mortises. Inspect the materials for gaps. You can decide whether to create a cap molding for the flush joint or leave the joint’s one side exposed for visual effect. You should also purchase a table saw mortise and tenon jig to guide you in making accurate tenons using your table saw. Moreover, it will help to have a dado blade for cutting dadoes.

This tenoning jig lets you create consistent and accurate cuts. When choosing a tenoning jig, it will be best to use something that you are comfortable with. The dado blade is a circular saw blade type that you can use with your table saw for cutting grooves and dadoes.

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Steps on How to Cut Tenons Using the Table Saw

As mentioned above, you need to acquire the necessary skills to make tenons and mortise joints. You can obtain such skills through an apprenticeship under a skilled woodworker. Yet, you can also develop such skills by watching informative videos and tutorials and applying what you have learned from those video tutorials. So, if you are desirous of learning these skills, you can check out the following steps on how to cut tenons using the table saw:

Step 1: Cut the Board to Length

Once you’ve prepared and inspected the materials, you can cut the workpiece or board you would like to have tenon to length. The necessary length, of course, is dependent on the workpiece size. If you build a 32-inch-wide screen door equipped with through tenons, you can cut your board up to 32 inches.  

Step 2: Determine the Size of the Tenons!

Ask yourself about how long you will need the tenon to be. If you use a 1×4 lumber, 3-1/2-inches wide, your tenon should be around 3-1/2-inch long likewise. So, you need to mark this measurement (3-1/2″) from the end of the board up to around the board. 

It will also help determine how thick your tenon should be. To achieve the ideal tenon thickness, you can divide the thickness of the board into thirds. In the case of the screen door project, the thickness is 3/4″. You will divide this thickness into three 1/4 inch measures. One-third of 3/4″ is 1/4″. So, the tenon thickness is around 1/4″.

Step 3: Set Up Your Table Saw

Once you’ve made the necessary measurements, you can then set up your table saw. Set the table saw fence to the tenon’s length (3-1/2″). Measure the distance from the saw blade to the saw fence. Make sure you got the correct measurement. Remember that for the joint to work well, you need precise measurements and cuts for your mortise and joints. 

Once you’ve set the fence, you can bring up the saw blade up to the height of your tenon. In the case of your project, you must remove 1/4″ of material on either side of your board. 

So, your tenon will be at the very board’s center. Hence, your saw blade must only be around a quarter of an inch above your table. Practice with a scrap first.

Step 4: Begin Cutting the Shoulder

Tenons don’t necessarily need to have a shoulder. But you will surely like having them, and it isn’t challenging to do. To cut it, you only need to turn the board onto its edge. Then, cut the shoulder in the same manner you’ve cut the thickness. Slowly work your way up to the fence. Don’t forget to use your miter gauge for this purpose.

You can adjust the height of the saw blade depending on the size you want to achieve with your tenon. Remember that the larger the tenon, the greater the glue area, and your joint will be more robust. Hence, it will be wise not to cut off much. Once done with cutting the shoulder, you can assemble the joint.  

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Safety Tips When Tenoning Using a Table Saw

Using the table saw for tenoning might be risky if you don’t use the right jig and set up. Yet, you can lessen the risks if you follow the following safety tips when cutting mortise and tenons on your table saw:

• Ensure that the wood is secured tightly inside your bench vise. If the wood is a bit shaky, then the cut will not be precise. Be careful likewise when using mallet and chisel, for, with the use of these tools, the risk of injuring yourself is higher. 

• Kickback can be very dangerous, and you should prevent kickback. Thus, you should avoid staying too close behind a running saw blade. In this way, you can avoid injuries due to kickback. 

• Don’t lift the table saw blade above the board you cut by more than a quarter of an inch. 

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Accuracy Tips While Cutting Mortise and Tenon Using the Table saw

Aside from knowing the safety tips, it will also help if you are familiar with the following accuracy tips when cutting mortise and tenon using your table saw:

• When selecting the mortise width, you should check if your chisel comes with a smaller width; otherwise, it will not fit onto the slot. 

• It will help if you also use a saw blade with the right number of teeth. Remember that the higher the teeth count, the cleaner the cut. Yet, it will also take longer to finish the cut. 

• Ensure that you cut outside the cutline when making tenons. In this way, the wood you will cut will have the right dimensions. 

• It will help to use the miter fence of your table saw. The miter fence can enable you to make square cuts perfectly.

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Conclusion

The mortise and tenon joints consist of two essential components: mortise hole and tenon tongue. The good news about tenons is that you can use any table saw utilizing either a dado blade set or a standard table saw blade. Moreover, you won’t need to have a huge table to make tenons. You can simply use your job site table saw using both the standard or dado blade sets. 

It will be good to note that you will have no fixed size for the tenon. Nevertheless, you should keep the mortise depth at about three times the tenon’s width. It will also help to remember that the tenon depth and mortise depth should be the same. Lastly, ensure that you have enough surface area to apply the glue on your tenon when cutting tenons.