CNC (Computer Numerical Control) is a technology where machines are controlled by computers using numerical data. It is a type of subtractive manufacturing.
1.2 Working Principle
The machine follows G-code instructions, which are commands that dictate the tool's movements and actions. Once programmed, the machine can run autonomously, reducing human intervention and increasing efficiency.
1.3 Common Materials
The commonly used materials include metals (such as aluminum alloys, stainless steel, brass, titanium alloys), plastics (such as ABS, polycarbonate, polyoxymethylene, nylon), wood (such as solid wood, MDF), and composite materials (such as carbon fiber reinforced plastic, glass fiber reinforced plastic).
1.4 Surface Finishing Methods
Sanding: Smoothing surfaces with sandpaper or abrasive tools.
Polishing: Creating a glossy finish.
Sandblasting: Using compressed air to blast abrasive particles onto the surface.
Anodizing: Forming a protective oxide layer on aluminum surfaces.
Electroplating: Depositing a metal coating onto the surface.
Coating: Applying protective or decorative coatings.
Laser Marking: Engraving text or images using a laser.
Heat Treatment: Altering material properties through heating and cooling processes.
2. Types of CNC Machine
2.1 By Shape
Vertical Machining Center (VMC): Spindle is vertical; suitable for flat parts.
Horizontal Machining Center (HMC): Spindle is horizontal; ideal for multi-sided parts.
Gantry Machining Center: Large machines for large workpieces.
2.2 By Axis
2-Axis CNC: Controls X and Z axes; basic linear cutting.
3-Axis CNC: Controls X, Y, and Z axes; versatile for various shapes.
4-Axis CNC: Adds a rotational axis (A or B); more complex shapes.
5-Axis CNC: Adds another rotational axis (C); highest precision and complexity.
3. Applications of CNC Machining
3.1 Industrial Applications
Automotive: Manufacturing engine components, body panels.
Aerospace: Producing aircraft parts with high precision.
Medical Devices: Fabricating surgical instruments and implants.
Electronics: Making circuit boards and connectors.
Tool and Die Making: Crafting molds and dies for injection molding.
4. Safety Training
4.1 Personal Protective Equipment (PPE)
Wear safety glasses to protect your eyes from flying debris.
Use dust masks to prevent inhalation of dust and fumes.
Wear ear protection to reduce noise exposure.
Use gloves when handling materials but avoid wearing them while operating the machine.
Wear long-sleeved clothing and avoid loose clothing and jewelry.
4.2 Emergency Procedures
Learn the location and usage of the emergency stop button.
Understand basic first aid procedures for burns, cuts, etc.
Locate fire extinguishers and know evacuation routes.
4.3 Machine Safety
Understand all parts and their functions.
Individual assignment:
1. Draw Sketches
1.1 Start SOLIDWORKS
Open the SOLIDWORKS software and select "New" > "Part" to create a new part file.
1.2 Draw Sketches
Click on the "Sketch" button to enter sketch mode. Use various drawing tools (like rectangles, circles, polygons, etc.) to draw the basic outline of the furniture.
1.3 Add Dimension Constraints
Use the "Smart Dimension" tool to add precise dimensions to sketch elements.
1.4 Add Geometric Constraints
Apply geometric constraints (such as horizontal, vertical, tangent, etc.) to ensure the accuracy and stability of the sketch.
1.5 Complete Sketch
Click "Exit Sketch" to finish the sketch drawing.
图片草图
3. Build 3D Models
3.1 Extrude Operation
Select the recently drawn sketch and click on the "Stretch|boss" tool. Input the extrusion height (Thickness of board，12mm) to form the solid entity of the furniture.
3.2 Chamfers and Fillets
Use the "Chamfer" and "Fillet" tools to refine edges, making the furniture look more aesthetically pleasing and safe.
图片3D拉伸
4. Perform Assembly
4.1 New Assembly
Select "New" > "Assembly" to create a new assembly file. Insert previously created parts into the assembly.
图片;组装后的作品
5. Output
5.1 Export Model
Use "File" > "Save As" to export the model in different formats (such as STL, STEP, IGES, etc.), ensuring compatibility with other software or for 3D printing.
5.2处理成G代码文件
Use the "Drawing" tool to create 2D engineering drawings, labeling dimensions and tolerances for manufacturing and processing.
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