Carbide Burr – The Basics
Rotary files are tools that remove unwanted edges from metals. Technically, burrs are excess and raised portions of a material after being exposed to certain process. You can sometimes see it as droplet-shaped flakes on the surface of your metal. It can also be seen as a fine wire at the edge of the material that you are working. The Carbide burr are tools that remove those unwanted edges through the process called deburring. It is composed of different sizes of cutters designed to clean, finish, smooth, and shape various materials. They are generally used for machine and metal works but is also applicable for dental purposes and jewelry making.
Deburring is important for complex machines like car engine because it affects the durability and accuracy of your machine. It also affects the aesthetic value of jewelries and metal crafts. In addition, unwanted burrs are typically sharp and might cause cuts on your skin.
Carbide Burrs According to Shapes
Different shapes of carbide burrs have their own advantages. You cannot maximize the features of a particular shape if you will use it for a different purpose. Knowing the shapes and its correct usage will help a lot in doing the job correctly.
The most common shape is the round bur. It is circular in shape and can be used at any angle. It easily fits to tight areas and is available in various diameters. Because of its shape, it is highly applicable for drilling, deburring and enlarging holes, and refining bezels at stone setting.
The Cone bur has a triangular shape. It can be used in deburring and enlarging holes, and is suitable when repositioning holes in flush setting. Typical cone burs have pointed tip but you can also have flat and rounded tips.
The Bud bur is slightly tapered on its curve and has a pointed tip. It has the same application as a triangular bur. The only difference is that triangular burs are used for flush setting while bud burs are used for stone setting.
Cylindrical burs have straight sides and are good alternatives for a file. It is useful for heavy deburring and in grinding inner ring shanks. It comes in various sizes and its end can be flat or rounded.
Cup bur resembles the shape of a cup for its head. It is used when rounding the ends of wires and when refining the prong tips. Because of its shape, it tends to clog easily so you should use it with lubricant to prevent clogging.
Carbide Burrs According to Cuts
Different cuts of carbide burrs are designed for specific applications. Each cut may come in all shapes and sizes to suit your varying needs.
Standard cut is an all-around cut designed for ferrous materials like iron, copper, and brass. It removes unwanted edges well and provides good finishing on the completed work.
Aluminum cut is widely known and you can easily find one on the market. It is used for non-ferrous and non-metallic materials. You can use aluminum cuts when you want rapid deburring with minimum chip loading.
Chip breaker cut is like a smaller and finer version of an aluminum cut. This cut has an improved controllability but reduces surface finishing.
Coarse cut burs solve chip loading problems on machine works. It is suitable for soft materials like copper, aluminum, plastic, and rubber. Cross cut burs are similar to a double cut file because it uses teeth instead of metal cuttings.
Fine double cut burs offers improved controllability and reduced size. It is useful when deburring heated metals and tough alloys.
Diamond cuts have diamond-shaped carvings on the surface instead of metal cuttings. This shape is ideal for glass, stone, and metal works. However, you should use diamond cuts with a lubricant.
Revolution versus Size and Cut
To produce best results, your operational revolution per minute should depend on the size and cut of your bur. Standard cuts should have higher RPM compared with double cuts. Smaller burs should also have higher RPM as opposed to burs with bigger diameter. The material you are deburring also affects the recommended RPM. Tough materials like titanium and stainless steel requires higher RPM than soft materials like plastic.
Repairing Your Bur
Burs also degrade and become dull with time. You can bring your carbide burrs for repair to make it as good as new. Some steps when repairing burs include checking and replacing the shank, brazing and turning the head, refluting, and polishing.