CNC machining involves carrying out tasks like drilling, boring and cutting under the instructions of a computer. With CNC, the machines make a set of instructions and specifications out of computer files and turns a piece of metal into a finished product by refining and cutting based on the instructions. It is a fast, repeatable, and efficient model that uses CNC controllers to perform complex cuts that would be too time consuming were it to be done manually. Businesses and individuals that do not possess precise machining tools and do not have repeatable parts production capabilities can save on time as well as money by utilizing CNC services.
Some of the Benefits of CNC Machining Include:
- Fewer mistakes caused by human error
- Consistency and repeatability
- Precision and accuracy
- Fast production
- Reduction of waste
- Reduction in operator/labour costs
Modern CNC services are automated and employ the use of computer-aided design (CAD) and computer-aided manufacturing (CAM) software. Usually, an engineer will input the design instructions by hand for the more simple design specifications and will employ the use of CAD and/or CAM software with more complex design work. Coordinate Measuring Machines (CMM’s) are also used to physically map objects to the system. Once the part is designed in the system, the software automatically formulates a series of steps that are followed systematically until the end goal is reached. During production, the machines follow these steps and the resulting end product are parts that are completely identical in every measurable metric.
There are quite a number of devices employed in CNC machining and they include:
- Mills, or milling machines are cutting machines which solid shape (typically stationary) workpieces using a movable and rotatable cutting tool. They can perform anything from simple keyway cutting to complex contouring tasks, and come in either vertical or horizontal orientations.
- Lathes are machines that cut cylindrical workpieces by rotating them at fast speeds against a stationary cutting tool. Because the cutting action on a lathe is uniform, they can only make symmetrical cuts. Lathes are used in making parts such as shafts and bushings.
- Grinders/grinding machines are tools used to grind down parts using abrasive wheels as cutting tools. Commonly used for high accuracy surface finishing, they can also grind larger volumes of metal depending on the application. They are typically the easiest type of CNC machine to work with.
- Electricaldischargemachines (EDMs) remove and form material using an electrical discharge. These machines typically work with hard metals which are much more difficult to machine via other methods.
- Water/abrasive jet machines use abrasives added to water and propelled in a high velocity to cut workpieces. They are designed to cut and shape heat-sensitive, thin, brittle, or hard materials as they can form intricate shapes.
The capabilities of CNC machining are vast and they can be used in drilling, milling, turning, broaching, deep drilling, etching, honing, jig boring, laser machining, screw machining, swiss machining, jet machining, and super abrasive machining to mention a few.
With regards to the materials that CNC services can work, there are actually a limited number and they depend on the capabilities of the equipment. Most equipment struggle to handle metals with high hardness without causing wear on the cutting tools. Some equipment also struggle with temperature sensitive materials.
It is also important to note that CNC service providers usually work on materials that fit specified dimensions as determined by their machinery and equipment.