Activity 001: CNC Router Component Identification & Inspection¶
Activity ID: U4M1-ACT-001 Duration: 35 minutes Objective: Students will identify, locate, and describe the function of all major CNC router components through hands-on machine inspection. Group Size: 2-3 students
Overview¶
Students will perform a structured walk-around inspection of the CNC router, identifying each major component, describing its function, and documenting its current condition. This activity builds the foundational vocabulary and spatial understanding needed for all subsequent CNC modules.
Materials & Equipment Needed¶
- CNC router (powered off, E-stop engaged)
- Component identification worksheet (provided)
- Flashlight
- Ruler or calipers
- Smartphone/camera for documentation
- PPE: Safety glasses
Instructions & Procedure¶
Phase 1: Orientation & Safety Briefing (5 minutes) 1. Instructor reviews E-stop location and confirms machine is powered off and locked out 2. Review the safety perimeter and pinch-point hazards even on a stationary machine 3. Distribute component identification worksheets to each group
Phase 2: Structural & Motion System Inspection (15 minutes) 1. Begin at the machine frame β identify material (steel/aluminum), construction method (welded/bolted), and note any visible wear or damage 2. Locate and identify the gantry assembly β measure the Y-axis span with a tape measure 3. Find the linear guides on each axis β identify type (supported rail, V-wheel, or unsupported rod) 4. Locate the drive mechanism on each axis β identify type (ball screw, lead screw, rack & pinion, or belt) 5. Find the stepper/servo motors β note the NEMA size printed on the motor label 6. Locate limit switches or proximity sensors on each axis β count total number 7. Find the controller enclosure β identify the controller board (GRBL, Mach, or proprietary) 8. Record all findings on the worksheet
Phase 3: Spindle & Work Area Inspection (10 minutes) 1. Examine the spindle β identify type (trim router or VFD spindle), note rated power and RPM range from the nameplate 2. Locate the collet and identify its size (ΒΌ", β ", ER20, etc.) 3. Examine the spoilboard β note material, thickness, and surface condition (flatness, previous cuts) 4. Identify any workholding features (T-slots, threaded inserts, vacuum zones) 5. Measure the approximate work envelope (X Γ Y Γ Z travel) 6. Document findings and take photos of key components
Phase 3: Group Presentation (5 minutes) 1. Each group presents their findings for 1-2 assigned components 2. Class discusses any discrepancies in identification 3. Instructor clarifies any misidentified components
Discussion Points¶
- Why does frame rigidity matter more than frame weight?
- What would happen if a limit switch failed during a homing cycle?
- How does the drive mechanism type affect the machine's accuracy and maximum speed?
- Why might a VFD spindle be preferred over a trim router in a makerspace?
Expected Outcomes¶
- Students can identify and name all major CNC router components without reference materials
- Students understand the functional relationship between components (e.g., motor β driver β lead screw β linear motion)
- Students can read and interpret machine nameplates and specifications
Assessment Rubric¶
| Criteria | Excellent (4) | Proficient (3) | Developing (2) | Beginning (1) |
|---|---|---|---|---|
| Component Identification | All components correctly identified and described | Most components identified with minor errors | Several components misidentified | Unable to identify basic components |
| Functional Understanding | Clearly explains how components interact | Explains individual functions accurately | Partial understanding of functions | Cannot describe component functions |
| Documentation Quality | Thorough notes, accurate measurements, clear photos | Good notes with minor gaps | Incomplete documentation | Missing or unusable documentation |
| Safety Awareness | Identifies all pinch points and hazards | Identifies most hazards | Recognizes obvious hazards only | Does not consider safety |
Safety Considerations¶
- Machine MUST be powered off and locked out during inspection
- E-stop must remain engaged throughout the activity
- Do not touch the cutting tool β bits may be sharp even when stationary
- Be aware of pinch points between gantry and bed
- Do not reach into the controller enclosure
Last Updated: 2026-03-19