Types of Carbide Burrs

Carbide burrs, also called rotary files or die grinder bits, are a go-to tool for shaping, cutting, and removing material in metalworking and other industries. Made from tough materials like Tungsten Carbide, they are designed to be used with a high-speed rotary tool.

The primary function of a carbide burr is to remove material quickly and precisely, making them suitable for deburring (removing sharp edges), sculpting, grinding welds, and enlarging holes.

What is a Carbide Burr?

A carbide burr is a specialized cutting tool typically made from Tungsten Carbide, a material that is significantly harder and more durable than High-Strength Steel (HSS). While HSS burrs exist, Tungsten Carbide burrs are preferred for metalworking because they can withstand the extreme heat generated during high-speed cutting without losing their edge or deforming. This superior hardness allows them to last longer and perform better on demanding jobs.

Types of Carbide Burrs

While tungsten carbide burrs can be used on most materials, they come in different "cuts," or flute patterns, that are optimized for specific jobs and materials. The two main types are single-cut and double-cut.

Single-Cut

This type has a single, right-hand spiral flute. It is designed for fast material removal and is ideal for use on harder materials like steel, cast iron, and copper. The long, continuous flute produces large chips and helps prevent clogging, making it a great choice for deburring and heavy stock removal. However, it does not leave as smooth a finish as a double-cut burr.

Double-Cut (Diamond or Cross-Cut)

This is the most common and versatile cut. It features a second set of flutes cut in the opposite direction, creating a crosshatch pattern. This design produces smaller chips and provides a smoother finish. Double-cut burrs are excellent for general-purpose applications, including medium stock removal, deburring, and fine finishing on a wide range of materials, including both ferrous and non-ferrous metals, plastics, and wood.

Types of Carbide Burr Shapes

The shape of a carbide burr dictates the kind of cut or profile it can create.

• Cylinder Burrs: Used for general-purpose material removal and creating flat surfaces.
• Ball Burrs: Perfect for carving, sculpting, and creating concave cuts.
• Tree Burrs (Pointed or Rounded): Used for rounding off edges and getting into hard-to-reach areas and angled contours.
• Inverted Cone Burrs: Designed for making V-cuts and creating chamfers on the backside of a workpiece.
• Flame and Oval Burrs: Used for shaping, contouring, and creating a variety of unique profiles.
• Countersink Burrs: Specifically designed for chamfering and creating beveled edges on holes.

Carbide Burr Speed

The rotary tool speed you employ will depend upon the metal and the size/type of burr used. It's always best for optimum performance and results to see the manufacturer's recommendations for the right RPM to use with each metal burr. Ideally, you'll begin at a lower speed and increase as you go along; however, if you discover your burr is chipping, it's a sign you're going too slow.

Best Practices for Using Carbide Burrs

To ensure optimal performance and extend the life of your burr, follow these guidelines:

• Control Speed (RPM): The speed of your rotary tool should be adjusted based on the size of the burr and the material being cut. Generally, a larger burr requires a lower speed, while a smaller burr requires a higher speed. Consult manufacturer recommendations.
• Apply Proper Pressure: Do not apply too much pressure. Excessive force can cause the burr's cutting edges to chip, which will dull the tool and reduce its lifespan.
• Keep It Moving: Keep the burr moving to avoid friction burns. Keep the tool moving across the cutting area to prevent clogging and to achieve a smooth, consistent finish.