Computer-aided manufacturing (CAM) also known as computer-aided modeling or computer-aided machining is the use of software to control machine tools in the manufacturing of work pieces. This is not the only definition for CAM, but it is the most common.
Computer-aided manufacturing (CAM) is the use of software and machinery to automate the manufacturing process. CAM systems use software to generate toolpaths for machines, industrial machinery to turn raw materials into products, and post-processing to convert toolpaths into a language machines can understand.
Based on this definition, a CAM system requires three essential components to function effectively:
1. Software that generates toolpaths, instructing the machine on how to create the product.
2. Industrial machinery capable of transforming raw materials into finished products.
3. Post-processing that converts toolpaths into a language that machines can understand.
These components are brought together through extensive human labor and skill. The manufacturing industry has invested years in developing and refining advanced machinery. Today, there is no design too complex for a proficient machine shop to handle.
CAD and CAM are intrinsically linked; without CAM, CAD designs cannot be brought to life. CAD focuses on the design of a product or part—its appearance, functionality, and dimensions. CAM, on the other hand, focuses on the manufacturing process. You can design the most elegant part in your CAD tool, but without an efficient CAM system to produce it, the design remains theoretical.
The engineering process starts with CAD, where engineers create either a 2D or 3D drawing. This could be a crankshaft for an automobile, the internal structure of a kitchen faucet, or the hidden electronics in a circuit board. In CAD, any design is referred to as a model and includes a set of physical properties that will be used by the CAM system to guide the manufacturing process.
When a design is complete in CAD, it can then be loaded into CAM. This is typically done by exporting a CAD file and importing it into CAM software. However, tools like Fusion 360 integrate both CAD and CAM functionalities, eliminating the need for import/export.
Once the CAD model is in the CAM software, the preparation for machining begins. Machining is the controlled process of transforming raw material into a defined shape through actions like cutting, drilling, or boring.
CAM software prepares a model for machining by performing several key actions:
- Checking for geometry errors: Ensuring the model has no issues that could impact the manufacturing process.
- Creating a toolpath: Generating a set of coordinates that the machine will follow during the machining process.
- Setting machine parameters: Configuring necessary settings such as cutting speed, voltage, cut/pierce height, etc.
- Configuring nesting: Optimizing the orientation of the part to maximize machining efficiency and material usage.
Modern manufacturing centers utilize various Computer Numerical Control (CNC) machines to produce precisely engineered parts. The process of programming these machines to perform specific tasks is known as CNC machining.
Before the advent of CNC machines, manufacturing was performed manually by experienced machinists. Automation has since revolutionized the industry. Today, human intervention is only needed for loading the program, inserting raw materials, and unloading the finished product.
CNC routers use high-speed spinning components to cut parts and carve various shapes. For instance, a CNC router used in woodworking can efficiently cut plywood into cabinet parts or perform complex decorative engraving on door panels. With 3-axis cutting capabilities, CNC routers can move along the X, Y, and Z axes.
These machines use precise lasers, high-pressure water, or a plasma torch to perform controlled cuts or engravings. While manual engraving techniques can take months, these machines can complete the same work in hours or days. Plasma cutters are particularly useful for cutting electrically conductive materials like metals.
Milling machines chip away at various materials such as metal, wood, and composites. They offer enormous versatility with different tools that meet specific material and shape requirements. The primary goal of a milling machine is to remove mass from a raw block of material as efficiently as possible.
Lathes also chip away at raw materials, but unlike milling machines, they operate differently. While milling machines use a spinning tool and stationary material, lathes spin the material and cut with a stationary tool.
EDMs cut desired shapes out of raw materials using electrical discharges. An electrical spark is generated between an electrode and the raw material, with the spark reaching temperatures of 8,000 to 12,000 degrees Celsius. This allows EDMs to melt through nearly anything in a controlled and ultra-precise process.
