Carbide burs, or carbide rotary files, are widely used in different industries today. These grinders (aka sharpeners) are indispensable tools in various fields like engineering, sculpting, woodcarving and more.
There are tons of these burs out in the market today, such as the tungsten carbide grinders. With a wide variety to choose from, picking the right bur can be a quite confusing task. Hence, here are some factors to consider in selecting the right carbide bur.
Rotary burs are not just exclusively made of tungsten carbide. These can also be made of other metals such as vanadium, tungsten, carbide, diamond and more. And these metals can be categorized into four.
The four main metal types are the following: high-carbon, high-speed steel (HSS), carbide, and diamond. Each type possesses different advantages and disadvantages, depending on several factors.
For instance, burs made up of high-carbon have high strength, wear resistance, and hardness. However, these good qualities compensate for the decrease in ductility, formability, machinability, and weldability of this type. These burs also require more maintenance, as these are more prone to rusting.
High-carbon burs also get more effective at slow speeds. In addition, these can also be used in performing more precise cuts than the other metal types.
On the other hand, HSS burs are heat and abrasion resistant. They have high edge retention and can withstand cutting forces. However, they have a lower usable cutting speed range than carbide.
HSS burs are also less prone to rust. Therefore, they do not require much maintenance than the other types. Basically, they have a higher lifespan and are also more affordable.
Carbide burs boast of their hardness and resistance to heat and wearing. This type is very durable, cut with less effort, and can be used for longer productions. The only disadvantage of tungsten carbide grinders is that they can chip or shatter faster than the other metal types.
Furthermore, tungsten carbide sharpeners can be cleaned with a propane torch. They also work best at medium to high speeds while maintaining a sharp edge.
On the contrary, diamond burs are known for their superior cutting and durability. They do not chip easily unlike carbide burs. However, they have comparably shorter lifespan than the latter.
Type of materials
Each metal type works differently on specific materials. Depending on which materials the burs will be used with, the results greatly vary.
For example, high-carbon burs perform best on the following materials:
- Nickel Silver
On the other hand, HSS is suitable for materials including:
While tungsten carbide grinders have the best effect on the following:
- Mokume Gane
- Stainless Steel
If working on the following materials, then use diamond burs:
- Precious and non-precious materials
How burs will be used
In choosing the right grinder, also determine how it will be used. Some types work best for a specific purpose. Therefore, determining which bur to choose depends on how one is planning to make use of it.
Remember that high-carbon burs can perform precise cuts and can be operated at lower speeds. These are great for intricate tasks such as stone setting. This also holds true for the HSS burs.
Meanwhile, tungsten carbide grinders are great for soft metals. These burs can be used for carving, deburring, finishing, shaping, and smoothing materials. They are also best used at high speed with light pressure.
Moreover, diamond burs can be used for carving, grinding, and sculpting. They work great for glass and stone materials.
Fluting in burs refers to the grooves on the bit’s surface. The more flutes there are, the more precise the cut can be made. There are different fluting styles, namely: single cut, double cut, diamond cut, and ripper cut.
In a single cut, metallic materials such as stainless steel and cast iron are given a general-purpose cut. This involves a fast stock removal and a good surface finish. It is also recommended in weld preparations.
Double cut, on the other hand, allows fast stock removal, perfect for increasing production rates. The chips break down as the material gets removed, which leads to a smoother running burr. It is ideal for materials that create long chips.
Meanwhile, diamond cut offers a staggered tooth formation, which provides more cutting edges. The edges penetrate the materials better and give a faster metal removal. It also offers improved tool control with smoother cutting action.
Lastly, ripper cut produces a good finish with minimum tooth loading. It has excellent stock removal and fast cutting action on non-metallic and non-ferrous materials.
Rotary burs also come in different shapes. Each is designed to perform a specific use. Choosing the right shape also boils down to how one is planning to use the tungsten carbide sharpeners.
The most common bur shapes are: ball, tree, inverted and pointed cone, round nose, cylinder, oval, flame, oblate spheroid, and countersink.
Ball or spherical shaped cones are used to shape and hollow out an area. These can also be used to make concave cuts in the material. Ball cones are typically used in wood and stone carving, as well as metal engraving.
On the other hand, tree burs are used for creating concave cuts or rounding off edges. If one wants to make v-cuts and rear side chamfering, then using the inverted cone tungsten carbide grinders is recommended.
Pointed cones and round nose burs, on the other hand, work best for surface finishing and rounded edges. These are recommended for materials with difficult to reach areas and tight or narrow angles.
Cylinder burs also work great for contour finishing, while oval, flame, and oblate spheroid are great for channel work and shaping. Furthermore, countersink tungsten carbide grinders work best for getting into acute angle areas, beveling, counterboring, and chamfering.
Familiarizing with the factors mentioned above will help anyone choose the right tungsten carbide grinders he needs.