Computer Aided Manufacturing

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In the theoretical classes we use the lecture method during the explanation of theoretical issues. In the laboratorial component, students have training sessions in CNC milling machine and create CNC programs. Some CNC programs are manually created and others are generated by CAM software. At the end the programs are loaded into CNC milling machine and performed to obtain parts.

Understand the main operations to obtain parts by chip removal, starting from an initial form, until their final dimensions and shape; To select tools and cutting parameters for machining operations; To build manually CNC programs for basic milling operations; To use Computer Aided Manufacturing software programs to create CNC programs for advanced machining operations; To perform the major procedures on a CNC milling machine.

1. Machining by Chip Removal

• Conventional and computer-controlled machine tools. Nomenclature of the axis system.
• Main chip removal cutting operations: Sawing; Drilling; Threading; Grinding; Boring; Turning; Milling.
• Cutting tools and cutting parameters. Calculation of cutting speed and feed rate.
• Machining force and power. Torque and power curves of a machine tool.
• Chip formation and heat generation during cutting.

2. Measuring Tools

• Operating principles and use of measuring instruments. Vernier caliper and inside and outside micrometers.
• Surface roughness tester (profilometer).

3. Additive Manufacturing Processes

• Operating principles and applications.

4. Numerical Control of Machine Tools (CNC)

• Relative and absolute coordinates. Cartesian and polar coordinate systems.
• Addressing for variable and parameter definition. CNC codes: Preparatory functions (G-codes), auxiliary functions (M-codes).
• Reference points: Machine zero and workpiece zero concepts. Tool change procedure.
• Tool length and radius compensation concepts.
• Linear interpolation at rapid and programmed feed rates. Circular interpolation at programmed feed rate. Circular interpolation block format using parameter R and using i, j, k vectors.
• Main program and subprograms.
• Drilling and threading cycles.
• Mirror function and workpiece zero shift.
• Execution of main operations on the Machining Center with Fanuc Series O-M Controller, and execution of CNC programs using metallic and polymeric materials.

5. CAD/CAM Technologies

• CAD/CAM systems and methodology for creating a machining program.
• Post-processing.
• Toolpath and permissible tolerance.

6. Computer-Aided Manufacturing (CAM) Software

• Mastercam program architecture.
• Creating and modifying entities.
• File conversion from CAD programs to Mastercam.
• Creation of 2D machining operations: Contours, facing, and pocketing.
• Drilling and threading cycles.
• Simulation of programmed toolpaths and post-processing.
• Transfer of CNC programs to the machining center and execution of CNC code.

NAO