Group Assignment Requirements
- Complete lab safety training for CNC operation.
- Test runout and spindle alignment.
- Evaluate fixturing methods.
- Test speeds, feeds, and toolpaths.
- Test machining performance on different materials.
- Document results on the group page.
Learning Outcomes
- Understand CNC machining constraints.
- Evaluate machine precision and alignment.
- Analyze cutting parameters and material response.
- Interpret how toolpaths affect surface quality and accuracy.
Progress Status
Summary of completed tasks for Week 07 – Computer-Controlled Machining.
Documented CNC structure, safety systems, electrical infrastructure and auxiliary systems.
Designed test model, configured tools, defined machining parameters and generated G-code.
Evaluation of runout, alignment, speeds, feeds, fixturing and material response.
1. CNC Machine Overview and Safety Infrastructure
The CNC router used in our lab was designed by SYNTEC. It integrates Japanese control software, Italian motors, and a Chinese structural chassis.
The machine operates under the G-code standard and supports up to 8 different tools in a single project. It follows a 3-axis prismatic milling method, where the material remains fixed and only the tool moves.
Safety Zone and Fire Protection
The machine includes a marked safety perimeter on the floor, indicating the restricted operator zone during operation.
Fire extinguishers are strategically placed both inside the machining room and at the Fab Lab entrance.
Electrical System and Power Control
The machine is connected to a regulated electrical panel that prevents overcurrent spikes and short circuits.
A master power switch controls the entire system, ensuring safe startup and shutdown procedures.
Control Panel and Emergency Systems
The control panel includes:
- Security key switch
- Phase activation switches
- Emergency stop button
- Visual alarm indicators
The interface allows monitoring of operational states: cutting mode, stop mode, and error alerts.
Remote Control Systems
Two remote controllers allow:
- Manual positioning of the spindle
- Work mode adjustments
Lubrication and Air Systems
The machine includes a pedal-controlled oil pump for lubricating moving components.
An air compressor ensures proper tool and material clamping.
Axes, Tools and Automatic Tool Change
The CNC operates on 3 prismatic axes (X, Y, Z). Multiple milling tools are available depending on cutting requirements.
The machine supports automatic tool change, allowing up to 8 tools per project.
CNC Router in Operation
2. Test Model Processing and CAM Workflow in Fusion 360
For the cutting and routing tests, a simple test model was designed in Fusion 360. The geometry consisted of a semi-oval block with engraved text on top (in this case, my name: Giussepe).
The objective was to machine the model on a 12 mm plywood sheet (triplex) to evaluate toolpath behavior and surface finish quality.
CAM Setup and Work Origin
After completing the solid model, the workflow moved to the Manufacturing (CAM) workspace.
The first step was defining the stock dimensions and establishing the work origin point. This ensures that the physical material aligns correctly with the virtual coordinate system.
Post-Processor Selection
The appropriate post-processor was imported to ensure compatibility with the CNC controller.
Selecting the correct post-processor guarantees that the generated G-code follows the syntax required by the machine.
Tool Geometry Configuration
Tool parameters were configured according to the actual milling bit used.
Measurements were verified using a digital caliper, considering tool diameter, flute length, and holder dimensions.
Cutting Parameters
Cutting parameters were defined as:
- Spindle speed: 19,000 RPM
- Feed rate: 1500 mm/min
These parameters were selected to ensure stable chip formation and avoid overheating during plywood machining.
2D Contour Operation
A 2D contour operation was selected to define the outer cutting boundaries.
A ramp-style entry strategy was used, with a 2.0° inclination and a 4 mm step-down, reducing tool stress during material penetration.
Toolpath Preview
The roughing contours and cutting direction vectors were visualized before execution.
Reviewing toolpaths helps detect potential collisions or inefficient movements.
Post-Processing and G-code Generation
Once validated, the operation was post-processed, generating the final G-code file.
This file contains the machine instructions controlling spindle speed, feed rates, and tool movement across X, Y, and Z axes.