What is a Riving Knife on a Table Saw (Ultimate Guide)

 

A riving knife is a crucial safety feature found on many modern table saws. It’s a flat piece of metal, mounted behind the saw blade, that moves up and down with the blade as you adjust its height. The primary purpose of a riving knife is to prevent kickback, which is one of the most dangerous hazards associated with using a table saw.

 

Understanding Kickback

Kickback occurs when a workpiece gets caught between the back of the saw blade and the fence or another object, causing the workpiece to be thrown back towards the operator at high speed. This can result in severe injuries or even fatalities.

 

How a Riving Knife Works

A riving knife works by keeping the kerf (the cut made by the saw blade) open and preventing the workpiece from coming into contact with the rear of the blade. When the workpiece is pushed through the blade, the riving knife follows the blade’s path, maintaining a consistent distance between the two. This helps to minimize the risk of the workpiece getting pinched, twisted, or otherwise caught on the back of the blade, which can cause kickback.

 

Riving Knife vs. Splitter

A riving knife is often compared to a splitter, another safety feature found on some table saws. While both devices serve the same purpose—preventing kickback—there are some key differences between the two:

1. Positioning: A riving knife moves up and down with the blade, maintaining a constant distance from the top of the blade. A splitter, on the other hand, is fixed in position and doesn’t move with the blade. This means that a riving knife is more effective at preventing kickback, especially when making non-through cuts (cuts that don’t pass all the way through the workpiece).
2. Shape: A riving knife is curved to match the profile of the blade, whereas a splitter is typically straight. This allows the riving knife to maintain a closer proximity to the blade, providing better protection against kickback.
3. Removability: Riving knives are generally easier to remove and reinstall than splitters. This makes it more convenient to switch between different cutting operations that may require the removal of the riving knife.

 

Importance of Using a Riving Knife

Using a riving knife on your table saw is essential for ensuring a safe and efficient cutting experience. It significantly reduces the risk of kickback and the potential for serious injuries. Always make sure your table saw is equipped with a riving knife or another anti-kickback device before operating it.

 

Adjusting and Maintaining the Riving Knife

It’s important to properly adjust and maintain the riving knife for optimal safety and performance:

1. Alignment: Ensure that the riving knife is correctly aligned with the blade. It should be centered in the kerf and parallel to the blade without touching the sides of the kerf. Misalignment can reduce the effectiveness of the riving knife and increase the risk of kickback.
2. Height: The height of the riving knife should be set slightly lower than the highest point of the blade. This ensures that the workpiece can pass over the riving knife without getting caught.
3. Cleaning: Keep the riving knife clean and free of buildup. Accumulation of sawdust and debris can interfere with the riving knife’s performance and contribute to kickback.

 

Riving Knife Compatibility

Not all table saws come with a riving knife, and older models may only have a splitter or no anti-kickback device at all. If you have a table saw without a riving knife, it’s worth considering upgrading to a model with this safety feature or retrofitting your existing saw with an aftermarket riving knife, if possible.

 

Riving Knife Thickness

The thickness of the riving knife should be slightly thinner than the saw blade to ensure smooth operation. If the riving knife is thicker than the blade, it may cause friction and binding while cutting, which can increase the risk of kickback. Check the specifications of your saw blade and riving knife to ensure compatibility.

 

Riving Knife Removal

There may be instances when you need to remove the riving knife temporarily, such as when performing non-through cuts like dadoes, grooves, or rabbets. In these cases, follow the manufacturer’s instructions for safely removing and reinstalling the riving knife. Always remember to reinstall the riving knife when you are finished with non-through cuts and before making any through cuts.

 

Additional Safety Precautions

While a riving knife is an essential safety feature, it’s crucial to follow other safety practices when operating a table saw:

1. Use push sticks and featherboards: These devices help guide the workpiece while keeping your hands a safe distance from the blade.
2. Wear safety gear: Protect your eyes with safety glasses, your ears with hearing protection, and your lungs with a dust mask.
3. Maintain a clean workspace: Keep your table saw and surrounding area free of sawdust, debris, and clutter to reduce the risk of accidents.
4. Follow the manufacturer’s guidelines: Always refer to your table saw’s user manual for specific safety instructions and maintenance procedures.

 

Conclusion

A riving knife is an essential safety feature on a table saw that significantly reduces the risk of kickback. It’s crucial to ensure that your table saw is equipped with a riving knife or another anti-kickback device and that it is properly adjusted and maintained for optimal performance. By taking these precautions, you can enjoy a safer and more efficient woodworking experience.