Learning Path & Checkpoints
Seven modules, in dependency order. Start at Module 1 and work through; each module has a checkpoint you must pass before moving on.
- Follow the seven-module sequence
- Identify checkpoint evidence
- Plan targeted review after an error
Concept
CNC programming is cumulative. Trying subprograms before you understand coordinates is like building a house from the roof. The path below follows the same seven modules as the course homepage; each links to the first lesson in that module.
Why It Matters
A structured path prevents the "I read everything but can't program anything" problem. Each checkpoint requires writing and verifying code — not just reading. Most new programmers get stuck because they try to jump from G01 to G76 without mastering offsets and coordinates.
How It Works
Estimated Time per Module
| Module | Topic | Est. Time | Difficulty |
|---|---|---|---|
| 1 | Foundations | 2–3 days | Beginner |
| 2 | Language and Control | 2–3 days | Beginner |
| 3 | Setup and Motion | 3–4 days | Intermediate |
| 4 | Milling Applications | 3–4 days | Intermediate |
| 5 | Turning Applications | 3–4 days | Intermediate |
| 6 | Verification and Projects | 4–5 days | Advanced |
| 7 | CAM and Further | Open-ended | Advanced |
Total beginner-to-competent: about 3–4 weeks of focused study. This is not a speed run — mastery comes from writing and debugging real programs.
Module 1 · Foundations
- What is CNC Programming?
- Machine Fundamentals for Programmers
- Safe Program Start & Restart
- Programming Math
- From Drawing to Process Plan
- Coordinate Systems
Checkpoint: Explain G90 vs G91 in your own words, and write the coordinate values for three points on a part drawing.
Module 2 · Language and Control
- Planes, Units & Numeric Conventions
- Reading & Structuring a Program
- G-Code Fundamentals
- Modal State & Execution
- M-Codes & Machine Functions
- Controller Dialects
Checkpoint: Read a 15-line G-code program and explain every line, including which codes are modal.
Module 3 · Setup and Motion
- Spindle Speed & Feed
- Work Offsets & Datums
- Tool Length & Geometry Offsets
- Rapid & Linear Motion
- Circular & Helical Interpolation
- Cutter Radius Compensation
Checkpoint: Set up G54 and H01 offsets, and write a linear profile program with G41 lead-in.
Module 4 · Milling Applications
- Milling Strategies: Facing, Slots, Pockets
- Drilling, Pecking & Boring
- Canned Cycles & Hole Patterns
- Tapping & Thread Milling
- Subprograms
Checkpoint: Drill a 4-hole pattern with G83 and a subprogram, then edit the depth in one place.
Module 5 · Turning Applications
- Turning Coordinates & Toolpaths
- Roughing & Finishing Cycles
- Grooving, Parting & Boring
- Single-Point Thread Programming
Checkpoint: Complete the stepped shaft turning project from drawing to program.
Module 6 · Verification and Projects
- Program Verification & First Article
- Diagnosing Program Problems
- Common Beginner Mistakes
- Project: Pocketed Mounting Plate
- Project: Stepped Shaft
Checkpoint: Run both projects through dry-run, single-block, and first-piece inspection.
Module 7 · CAM and Further Applications
- CAD, CAM & Post-Processing
- Macro Programming Foundations
- Rotary Axes & Probing
- Cycle Time & Process Improvement
- Exercises & Final Assessment
Checkpoint: Read a random shop-floor program and explain every line; pass the final exercises.
Example
If you're starting now: do Module 1 first. Don't skip to G-code projects. Coordinates and offsets are the foundation; everything else builds on them.
Common Mistakes
- Skipping modules — if you can't explain G90 vs G91, don't start subprograms.
- Reading without practicing — every checkpoint requires writing code, not just reading.
How to Use This Path
Work through the levels in order. Level 1 is not optional: a programmer who skips coordinate systems and offsets will crash machines on Level 2. Each lesson should end with you able to explain the concept out loud and trace a small program by hand. If you cannot explain G54 to a coworker, do not move on to canned cycles.
Level 3 is where the work pays off: you can read a drawing, choose tools, write a complete program, and verify it on the machine. Level 4 (macro programming) is optional and only worth it if your shop runs repetitive parts that benefit from parameterization. Do not start macros until you can hand-write and debug a complete turning or milling program without help.
Revisit the reference page when you forget a code — that is what it is for. The exercises page is where you prove you understand, not where you first learn.
Level 1 Checklist
Before moving to Level 2, you should be able to: (1) explain the difference between machine zero and work zero; (2) write a startup block G21 G17 G90 G94 G40 G49 G80; (3) trace a 10-line G01 program and state the tool position at each line; (4) explain why G43 H is needed and what happens if H is 0; (5) state the difference between G90 and G91. If any of these is shaky, revisit that lesson — do not proceed.
Level 2 adds canned cycles, cutter compensation, and multi-tool programs. By the end of Level 2 you should be able to write a complete 2-tool milling program that faces a block, mills a pocket, and drills four holes, then verify it on paper. Level 3 is the turning and milling projects on this site; Level 4 is macros.
Practice
1. What should you learn first?
Ans
Coordinate systems (Module 1). Everything else depends on them.
2. When are you ready for subprograms?
Ans
When you can write and verify a basic drilling cycle with G83 and G80.
3. What's the Module 1 checkpoint?
Ans
Explain G90 vs G91 and write coordinates for three points on a part drawing.