To start any CNC project, you first need to have or create a design before you can automate the manufacturing process for production. This process is typically managed using CAD and CAM software tools, which together form the backbone of CNC machining workflows.
CAD (Computer‑Aided Design)
Computer‑Aided Design (CAD) is the first step in the digital manufacturing process. It allows users to create highly detailed and precise digital representations of objects.
- Purpose: Design detailed 2D & 3D models.
- Function: Enables various disciplines to create or modify digital models, most commonly architects, designers, draftsmen and engineers.
- Role: CAD is the first step in CNC machining, where the design of the product is created.
- Who uses it: Designers, engineers, architects.
CAD software is widely used across industries such as architecture, product design, and engineering. The output from CAD—whether a 2D drawing or a 3D model—acts as the blueprint for subsequent manufacturing steps.
CAM (Computer‑Aided Manufacturing)
Computer‑Aided Manufacturing (CAM) takes the CAD model and translates it into actionable data for production machines like CNC routers. It’s where design meets automation.
- Purpose: Generate toolpaths and instructions for CNC machines by converting 2D & 3D models into machine‑readable language, usually G‑code.
- Function: Prepares the instructions used by CNC machines to transform raw materials into finished products.
- Role: CAM takes the CAD design and generates the toolpaths and G‑code necessary for manufacturing, making it an essential tool for CNC machining.
- Who uses it: Machinists, manufacturing engineers, CNC operators.
CAM software interprets CAD files, sets toolpaths, and manages machining strategies such as cutting depths, feed rates, and tooling selections.
Post Processor
The bridge between CAM-generated toolpaths and the CNC machine’s specific language is the post processor. It ensures that the instructions sent to the machine are precisely tailored.
- Purpose: Format toolpaths generated by CAM software into G‑code customised for the specific CNC machine.
- Function: Incorporates machine‑specific instructions like tool changes, coolant commands, and safety protocols.
- Details: Post processors must be configured for the OEM, machine model, and any unique features. Most CAM platforms include built‑in post processors or allow customisation.
Correct post processing ensures that every instruction—from spindle speed to material changes—aligns with the exact specifications of the CNC system in use.
G‑code Sender
G-code is the standard language used to control CNC machines. It contains a set of instructions that tells the machine where to move, how fast to move, and what path to follow.
- Purpose: Send G‑code to the CNC controller.
- Function: Acts as the communication bridge between the CAM software output and CNC hardware.
G-code is generated by CAM software and refined through the post processor. The sender transmits this code to the machine’s controller. A G-code file may include hundreds or thousands of instructions, such as movement along specific axes, spindle on/off commands, and more. Popular G-code senders include standalone applications or built-in utilities within CNC controllers, which read and execute the code line by line to produce the physical product.
How CAD/CAM Work Together
The process of going from idea to finished object with a CNC router follows a clear sequence:
- CAD: Create the design.
- CAM: Generate the toolpaths and G‑code.
- G‑code Sender: Transmit the G-code to the CNC machine to execute the manufacturing process.
This seamless digital workflow allows manufacturers to move efficiently from concept to creation, ensuring precision and repeatability in production.
Key Differences between CAD & CAM
Feature
CAD (Computer‑Aided Design)
CAM (Computer‑Aided Manufacturing)
Primary Goal
Design & Create Digital Models
Plan & Control Manufacturing Processes
Function
Drawing, Modeling, Simulation, Drafting
Generating Toolpaths & G‑code
Input
Ideas, Specifications
CAD Model
Output
Digital Drawings, 3D Models
Machine Code (G‑code), Toolpaths
User
Designers, Engineers, Architects
Machinists, Manufacturing Engineers
Stage
Beginning of Product Lifecycle
Production Stage
Analogy
Architect’s Blueprint
Builder’s Step‑by‑Step Instructions
Integrated CAD/CAM
Many modern software platforms—such as Autodesk Fusion 360—combine CAD and CAM in the same workspace, so when you tweak the model, the related toolpaths update automatically. This integration improves productivity, eliminates redundant steps, and reduces the potential for user error.
CAD and CAM in CNC Machining Workflows
In a typical CNC workflow, the process begins with the creation of a digital model using CAD software. This model serves as the blueprint for the part or product to be manufactured.
Once the design is finalised, CAM software is used to generate the necessary toolpaths and G-code, translating the digital model into instructions that a CNC machine can execute.
The G-code is then sent to the CNC machine, which follows the instructions to cut, drill, or mill the material, producing the final physical part. This workflow allows for high precision and repeatability, making it ideal for applications ranging from prototyping to full-scale production.
How CAD and CAM Work with Tekcel CNC Routers
Tekcel CNC routers are designed to integrate seamlessly with both CAD and CAM software, facilitating a streamlined workflow from design to production.
Users can create detailed designs in their preferred CAD software, which are then imported into CAM software to generate the appropriate toolpaths and G-code.
The generated G-code is compatible with Tekcel’s CNC control systems, ensuring that the machine executes the instructions accurately. This compatibility allows for efficient production of complex parts with high precision, catering to various industries and applications.
Learn More
Visit Tommotek to learn more about using CAD and CAM for CNC.