8. Computer Controlled Machining

Assignments and Assessment

Group Assignment

• Complete your lab's safety training
• Test runout, alignment, fixturing, speeds, feeds, materials, and toolpaths for your machine
• Document your work on the group work page and reflect on your individual page what you learned

Individual Assignment

• Make (design + mill + assemble) something big

Learning Outcomes

• Demonstrate 2D design development for CNC milling production
• Describe workflows for CNC milling production

Checklist: Have you answered these questions?

• Linked to the group assignment page
• Documented how you designed your object (something big)
• Documented how you made your CAM toolpath
• Documented how you made something BIG (setup, fixings, joints, feeds/speeds, etc.)
• Described problems and solutions
• Included design files and a 'hero shot' of the final product

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Basic Concepts

Recommended Resources

CNC Cookbook – CNC Router Easy Guide:
A practical guide covering CAD/CAM software, speeds and feeds, CNC router setup, and G-code programming. Also introduces G-Wizard, a tool for optimizing cutting parameters — great for both beginners and professionals.

Siemens Manuals – NC Programming Guide:
An official guide for Siemens NC programming, covering topics like tool change procedures, spindle motion, coordinate transformations, feed rate control, and tool radius compensation. Essential for CNC engineers using Sinumerik systems.

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Tool Parameters

Different tools serve various machining purposes. Drill bits cut axially to create cylindrical holes, while end mill bits are used for lateral cutting, slotting, and carving.

Difference Between Drilling and End Milling

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NC 1213 CNC Router Specifications

Cutting Direction, Feed Rate, and Spindle Speed

Working Area

• 1200 mm x 1300 mm (1.2m x 1.3m)
  (Model name NC 1213 corresponds to these dimensions)

Frame and Build

• Heavy-duty steel frame (reduces vibration)
• Linear guide rails for precision movement
• Gantry-style bridge for cutting stability

Spindle

• Air-cooled or water-cooled HQD spindle
• Power: 1.5 kW to 3 kW, depending on configuration
• ER collet system for tool holding

Control System

• Compatible with NcStudio or Mach3 software

Drive System

• Ball screw transmission on Z-axis (high precision)
• Rack and pinion drive on X and Y axes (high speed)

Supported Materials

• Wood, MDF, Plywood
• Acrylic, Plastics, PVC
• Aluminum (with proper feeds and tooling)

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Wood Router Bit Set

This is a set of profile and edge router bits designed for handheld or table-mounted routers, suitable for wood, plywood, MDF, and other wood-based materials. Made from tungsten carbide with non-stick red coating to reduce overheating and chip buildup.

Typical Uses:

• Grooving and rabbeting
• Profiled edge finishing
• Decorative edge shaping
• Chamfering and rounding edges

Ideal for carpenters, cabinetmakers, and woodworking professionals for both decorative and structural processing tasks.

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Engraving and CNC Router Bit Set

This set contains engraving, milling, and drilling bits, ideal for high-speed rotary tools like Dremel, Proxxon, or desktop CNC routers. They are compatible with 3.175 mm (1/8 inch) collet chucks.

Bit Types:

• Engraving needles (V-shape bits) – for fine detail and V-carving
• Cylindrical straight bits (flat end mills) – for pocketing and material removal
• V-bit engraving cutters – ideal for wood and plastic engraving
• Chamfer and profiling bits – for edge finishing
• Ball nose end mills – for 3D carving and surface modeling

Applications:

• CNC routers and laser engravers
• Dremel rotary tools and mini-grinders
• Wood carving and detailing
• Acrylic and PVC engraving
• PCB (Printed Circuit Board) milling
• Decorative edge shaping and fine finishing

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Software

NcStudio AD

NcStudio AD is a professional CNC machine control software used in wood processing, plastic engraving, acrylic cutting, MDF milling, and other general CNC operations.

Features:

• G-code file support (.nc, .tap, .txt, .gcode)
• 2D and 3D CNC machining
• Jog Mode for manual axis movement
• Zero point (X, Y, Z) setup
• Spindle speed and feedrate control
• Real-time toolpath visualization
• Start, Stop, Pause functionality
• Compatible with NcStudio PCI/USB motion control cards

Applications:

• Wood carving and furniture manufacturing
• Acrylic and plastic engraving
• Advertising product production
• 3D relief and decorative panel milling

Advantages:

• User-friendly interface
• Accurate and stable control system
• Widely used in industrial and hobby-level CNC routers

Work progress

Spindle

Fixing the material to the machine worktable

Drilling comes first because the material is too rigid.

Then we attach the material to the machine bed with screws.

I fixed the material to the worktable.

Time to start working.

I created the design in NcStudio AD that I want to mill, taking into account the material’s surface/coating.

Then I sent the file to the CNC machine via NcStudio AD and turned it on. You can see how the machine is working.

Watch the video on Vimeo

Final Result of CNC Milling

This is the final result of the CNC milling process. The word "YESSENOV" was successfully milled into the wooden surface using a flat end mill bit. The design was created in NcStudio AD and accurately followed by the machine.

📝 Cutting Quality Analysis:

• Cutting quality: The edges are clean and smooth, indicating that spindle speed and feed rate were well configured.
• Depth precision: The milling depth is consistent across all letters, showing correct Z-axis calibration and proper machine leveling.
• Surface finish: The surrounding surface is neat and undamaged, with minimal chipping.
• Letter clarity: The letter shapes are clearly visible, with decorative internal textures preserved.
• Material compatibility: The wood material handled the milling process well and maintained structural integrity.
• Overall result: The final product meets the expected design quality and demonstrates precision, accuracy, and clean finishing.