A guide to router bits: The different options available

If you’re diving into the world of CNC machining or woodworking, you’ll quickly realize that router bits are the unsung heroes of your tool collection.

Whether you’re a hobbyist or a seasoned pro, understanding the different types of router bits and their uses can make all the difference in your projects. Let’s break down the various options available and how each can enhance your work.

What are router bits?

Before we get into the nitty-gritty, let’s start with the basics. Router bits, like LMT Onsrud bits, are cutting tools used with a router to hollow out (or rout) an area in hard materials like wood, plastic, or metal. They come in a variety of shapes and sizes, each designed for specific tasks. Think of them as the brushes in your painting toolkit—each one has a unique role to play in bringing your vision to life.

Types of router bits

Router bits can be categorized in several ways, but we’ll focus on the most common types and their primary uses. Understanding these will help you choose the right bit for your project, ensuring a smooth and professional finish.

1) Straight router bits

What They Do: Straight router bits are the go-to for making straight cuts in material. They’re perfect for creating grooves, dados, and rabbets.

Best for: 

  • Cutting slots and grooves
  • Mortising
  • Dado cuts

Pro tip: For a cleaner cut, make multiple passes instead of trying to remove too much material at once. This reduces the strain on your bit and router.

2) Flush trim router bits

What They Do: These bits are used to trim the edge of one material to be flush with the edge of another. They come with a bearing that guides the bit along the edge of the material, ensuring a perfect match.

Best for: 

  • Trimming laminates
  • Pattern work
  • Template routing

Pro tip: Keep an eye on the bearing – if it gets worn out, it can mar your workpiece. Regularly check and replace the bearing as needed.

3) Chamfer router bits

What they do: Chamfer bits are designed to cut a bevel on the edge of a material, typically at a 45-degree angle. They’re great for decorative edges and joinery.

Best for: 

  • Adding decorative edges
  • Creating beveled edges for joints
  • Chamfering edges for a smoother finish

Pro Tip: Adjust the depth of the cut to change the size of the chamfer, giving you flexibility in your designs.

4) Round-over router bits

What they do: These bits are used to create rounded edges on your workpiece. The radius of the round-over can vary, giving you options for different levels of rounding.

Best for: 

  • Smoothing sharp edges
  • Creating rounded edges on furniture
  • Adding a professional touch to tabletops and shelves

Pro tip: For a more pronounced effect, use multiple passes, gradually increasing the depth of the cut.

5. Rabbeting Router Bits

What they do: Rabbeting bits are designed to cut a step-shaped recess along the edge of a material. This is essential for creating rabbets for joints.

Best for: 

  • Edge joinery
  • Making rabbets for cabinet backs
  • Creating recesses for glass panes

Pro tip: Using a rabbeting bit with interchangeable bearings allows you to change the depth of the rabbet without switching bits.

6) Cove router bits

What They Do: Cove bits are the opposite of round-over bits—they create a concave, rounded groove in the material. They’re ideal for decorative edges and moldings.

Best for: 

  • Adding decorative grooves
  • Edge detailing on furniture
  • Creating classic moldings

Pro Tip: Pair cove bits with round-over bits to create custom profiles for your projects.

Choosing the right router bit material

Just as important as the type of router bit is the material it’s made from. The most common materials are high-speed steel (HSS) and carbide. Let’s explore the benefits of each.

High-speed steel (HSS)


  • Less expensive
  • Easy to sharpen


  • Dulls faster than carbide
  • Not suitable for hard materials

Best for: 

  • Softwoods
  • Occasional use



  • Longer-lasting
  • Stays sharp longer
  • Suitable for hard materials


  • More expensive
  • Brittle (more prone to chipping)

Best for: 

  • Hardwoods
  • Professional and frequent use

Maintaining your router bits

Keeping your router bits in top condition ensures clean cuts and prolongs their lifespan. Here are some tips for maintaining your bits:


After each use, clean your router bits to remove resin and pitch build-up. Soak them in a bit of cleaning solution and use a brush to scrub off any residue.


Over time, even carbide bits will dull. Invest in a quality sharpening system or take your bits to a professional sharpener. Regular sharpening maintains cutting efficiency and precision.


Store your router bits in a protective case to prevent them from knocking into each other and getting damaged. A dedicated bit holder or rack is ideal for organization and accessibility.

Tips for using router bits safely

Safety should always be your top priority when working with routers and bits. Here are some essential safety tips.

Wear safety gear

Always wear safety glasses to protect your eyes from flying debris. Ear protection is also a good idea, as routers can be quite loud.

Secure your workpiece

Use clamps or a vise to secure your workpiece. This prevents it from moving during the routing process, ensuring accurate cuts and preventing accidents.

Use the right speed

Different materials and bit sizes require different router speeds. Refer to your router’s manual and adjust the speed accordingly to avoid burning the material or damaging the bit.

Keep hands clear

Always keep your hands clear of the bit. Use push sticks or other tools to guide the material through the router, especially when working with small pieces.

Routers play a crucial role

Router bits might seem like small, insignificant tools, but they play a crucial role in woodworking and CNC machining. By understanding the different types of bits and their uses, you can elevate your projects from amateur to professional quality. Remember to choose the right material for your bits, maintain them properly, and always prioritize safety. Happy routing!

With this guide, you’re now equipped to make informed decisions about which router bits to use for your next project. Get out there, experiment with different bits, and see how they can transform your work. Your creativity is the only limit!