CNC Router Bits

Guide to Choose CNC Router Bits

1. Choose the drill shape that suits your project.

2. Choose the suitable material

3. Do your best

4. Balance your need for edge speed

5. Choose the correct bit direction

6. Set the paper feed speed

7. Sharpen and re-sharpen bits

8. Store your bits

9. Specialty bits 

CNC Router Bits Features

First, we need to distinguish between drills and milling cutters.

Drill bits: These drill bits enter the material. They are the best choice for tasks that require the removal of material directly from the workpiece. They are usually used for pre-drilling screw holes.

Milling cutters (or milling cutters, engraving cutters and end mills): These milling cutters cut transversely on your material. They are designed to move on the surface of the workpiece and remove chips to achieve 3D design.

Even if the drill bit falls into these two main categories, other variables always play a role, such as drill bit material (carbide, high-speed steel, cemented carbide), flute type (straight, upper cut, lower cut, compressed), number of blades (1 -2 slot, 2+ slot) and the end of the drill (fishtail, engraving, V-drill, round head).

There are also dedicated bits that have more complex configuration files suitable for various dedicated applications. For example, they can be used to drill holes, etch glass or make dovetails. This means you need to investigate which point best suits your needs. Some noteworthy special bits include the boring bit, the miter folding bit, the rounding bit, and the "context" bit.

Materials of CNC Router Bits

Some common materials of CNC machine bits include:

High Speed Steel (HSS): This is a tool steel drill bit with high heat resistance, wear resistance and hardness. When used for cutting tools and drills, it is much better than carbon steel and is mainly recommended for cutting foam. HSS is processed from the original ore and heated to its melting point, and then a variety of elements and minerals are added to enhance the internal structure. Compared with cemented carbide, HSS tool life is short.

Solid carbide (SC): A strong and wear-resistant steel. There are different types of SC drill bits, from cheap drill bits to expensive high-quality drill bits. When buying SC drill bits, you must be extra careful, otherwise they will eventually be eliminated. Carbides come in many forms (tungsten carbide, beryllium carbide, silicon carbide, etc.). Please note that these drill bits can be brittle and should be handled with care.

Cemented carbide cutter head: Because cemented carbide is expensive, a large-diameter CNC milling cutter bit brazes a large amount of cemented carbide to the steel body. Then, you can get the life of the cemented carbide at a lower cost of the steel core.

Solid tungsten carbide drill bits: Tungsten carbide drill bits are made of hard tungsten carbide particles combined with metallic cobalt. These drill bits have super strength and durability, so they stay sharper for a longer period of time than HSS drill bits.

Polycrystalline diamond (PCD) drill bits: These drill bits consist of diamond particles sintered with a binder. Diamonds are mixed into a cemented carbide matrix to make a very hard and wear-resistant drill bit.