CNC Router Bits Buying Guide
CNC routers need bits, and these bits determine the carving type, resolution, and material.
While CNC machines have opened all kinds of creative possibilities, the magic lies in the bit. It determines whether you will end up with a perfect or okay design. Plus, it also makes the difference between cutting down on waste or increasing material costs significantly.
A CNC router can be used to produce items such as door carvings, interior and exterior decorations, wood panels, sign boards, wooden frames, moldings, musical instruments, furniture. In addition, they see use in industry in the thermoforming of plastics by automating the trimming process. CNC routers can help ensure part repeatability and sufficiently efficient output for production, or allow one-off designs to be made. This is engraving machine.
- Wood: A CNC wood router is a computer-controlled router tool that carves/etches objects or images into the face of a piece of wood. The CNC Router is ideal for hobbies, engineering prototyping, product development, art, and production works. The CNC works on the Cartesian coordinate system (X, Y, Z) for 3D motion control; however, typical CNC operated systems can only make carvings on flat planes.
- Metal: Milling is the machining process of using rotary cutters to remove material from a workpiece advancing (or feeding) in a direction at an angle with the axis of the tool. It covers a wide variety of operations and machines, on scales from small individual parts to large, heavy-duty gang milling operations. It is one of the most commonly used processes in industry and machine shops today for machining parts to precise sizes and shapes.
- Stone: A stone CNC router is a type of CNC router machine designed for marble, granite, artificial stone, tombstone, ceramic tiles, glass machining, polishing for arts and crafts, etc. Wood, metal and stone require different “bits” or “inserts”. There is bit call as diamond tools with different diameter 4mm,6mm,8mm mainly used.
- Polyurethane foam: Polyurethane foam can also be cut using a CNC router in order to produce complex shapes which would otherwise be difficult or impossible to replicate by hand. Depending on the type of foam being converted, a CNC router would be able to cut through up to an 8lb density. By converting a CAD design file into a CAM file, the CNC Router is able to read relevant information and produce a highly accurate finished product.
Types of CNC Router Bits
CNC router bits do not come in a single type. The types of router bits that are the most common are discussed below:
- Upcut: The upcut router bits are used when you need to remove chips at a fast pace or for slotting and grooving. An upcut bit usually pulls the workpiece up and does not leave much of a clean cut. Besides, pulling up the workpiece might result in a bit of damage.
- Downcut: The downcut bits cannot remove chips as fast as the upcut ones do, but they are great for leaving a smooth finishing on the material. These are best for thinner materials, though.
- Diamond Cut: Diamond cut materials are more popularly used with composites and PC board materials. They leave the finishing of the product smooth and clean but have a very limited material-removing capacity.
- Chipbreaker: The chip breaker does exactly what its name suggests, break chips, and that too at a very fast pace. These are also known as roughers.
- Straight Flute Cutter: These are the cheapest kind among all these, and also the simplest. It basically cuts up the material all at once, so it cannot be used for detailed work and carvings.
If you're getting into CNC routing (or even thinking about it), you're probably focused on the amazing projects you'll be able to do because of the incredible precision of CNC machines. That's understandable: Computer numerical control technology can open all kinds of new creative possibilities, whether you're making signs or cutting out project parts. But, as with any other kind of routing, the magic is made at the tip of a bit — maybe several different bits — and you're going to want to have the right cutters in your CNC toolbox.
As with regular routing, perhaps the most important variable when it comes to bits is shank size. You might find a bit that's the perfect profile for the job, but it'll prove useless if it's got a 1/2" shank and your CNC machine is equipped with a compact router that accepts only 1/4" shank bits.
But, beyond that, which bits do you need? The answer to that question is likely to change over time, as your projects evolve. But here's a look at some of the most widely used CNC router bits and what they can do.