Lecture 2

Terms of Reference: 

• CNC, CAD, CAE, CAM, CIM

• Digital design and digital fabrication 

• Dimension (D) [0D, 1D, 2D, 3D, 4D, 5D, 6D, ...]

• Raster and Vector (Illustrator vs Photoshop)

• Design for Manufacturing and Assembly (DFMA)

Measurement Fundamentals:

• Metric vs English Units (mm, cm, in, px, ...) - Conversion factors 

• Tools (Rulers - Calipars - Span - Coin for Scale, ...)

• Calibration

• Tolerance

• 2D CAD Walkthrough

  • Fusion 360 user interface

  • Sketching (create, modify, dimension, constraints) 

• Laser Cutting

  • Applications (Furniture, packaging, education, textile, jewelry, art, MFG and industrial, medical, ...etc.)

  • Variations: Scales - Technologies - User Interface

  • How a laser cutter works

  • Laser cutting workflow (CAD > Material selection > CAM > M/C setup and operation > Post-processing)

    • CAD

      • Software: Fusion 360, Inkscape, CorelDRAW, Illustrator, ... etc. 

      • File formats/extensions: dxf, ai, svg, dwg, pdf, png, ...etc. 

    • Material selection: Plywood, MDF, cork, cardboard, foam, leather, acrylic, ... etc. 

    • CAM

      • Software: Laser works, RD works, Laser CAD, SmartCarve, ... etc. 

      • Modes: Cut, scan/engrave, etching

      • Layers: colors for modes

      • Speed (mm/s) & Power (% tube power)

      • Kerf = beam diameter / 2

    • M/C setup and operation (Move xyz, focus, origin, frame, work time, EMERGENCY, ... etc.)

    • Post-processing (Sanding, painting, gluing, assembly, joining, ...)

• Design for Laser Cutting

  • • Avoid intersecting or common lines.

    • Engrave Lines: Use thicker strokes or fills for engraving.

    • Kerf Compensation: Account for material removed by the laser beam (kerf), typically 0.1–0.2 mm.

    • All holes and cutouts are at least 50% material thickness.

    • All texts have been converted to outlines or paths. 

• Case Study : Laser-Cut Laptop Stand

• Safety

• • Make sure nozzle air flow is working

  • Make sure machine vacuum is working 

  • Close the lid [1:20]

  • Stay around! Never leave [0:20]

• What can go wrong with a laser cutter?

  • • What can go wrong with a laser cutter ?

    • Air compressor malfunction: Material on fire!!

    • Vacuum malfunction: Smoke everywhere.

    • Laser beam misalignment 

• 3D CAD Walkthrough

  • Solid modeling (create, modify, dimension)

  • 3D Features (Extrude, Revolve, Sweep, Loft, Hole, Thread, ....etc)

• 3D Printing

  • Applications (Architectural models, medical equipment, aerospace, automotive, education, ...)

  • 3D Printing workflow (CAD > Technology selection > Material selection > CAM > M/C setup and operation > Post-processing)

    • CAD

      • Software: Fusion 360, SolidWorks, Rhino, Inventor, NX, ...etc. 

      • File formats/extensions: STL, OBJ, 3MF, AMF, ...etc.

    • Technology selection

      • 7 different technologies

      • Selection criteria (cost, visual appearance, availability, accuracy, functional requirements, ...)

    • Material selection: 

      • Based on the selected technology (polymers, metals, composites, food, stem cells ...)

      • FDM materials: PLA, ABS, PETG, TPU, Nylon, PC, ... etc. 

    • CAM "Slicing" *for FDM technology*

      • Software: Ultimaker CURA, Simplyfy 3D, Slic3r, Prusa Slicer, ... 

      • Printer settings: model/brand, volume, nozzle(s) size, no. extruders, ...

      • Filament settings: filament diameter "1.75 or 2.85 mm", melting temperature, cooling rate, ...

      • Print settings: layer height, infill, bed temperature, printing and travel speed, support, build plate adhesion, ...

    • M/C setup and operation (upload file, load/unload filament, bed leveling, calibration, tuning, ... etc.)

    • Post-processing

      • Cleaning & prepping: support removal, sanding, cold welding, gap filling

      • Finishing: priming, painting, vapor smoothing, polishing, epoxy coating. electroplating 

• Design for 3D Printing

  • • Design considerations: Layer height, shrinkage & warping, support structure, fillets

    • Design rules

• Case Study: Design and 3D Print Your Own Phone Case

• Safety

• Beware of the hot parts

• Watch the first five layers

• What can go wrong with a 3D Printer ?

  • • Forgetting the Filament 

    • Machine Calibration Fail

    • Heating Fail 

    • Clogging due to: dust, temperature, nozzle problems

Mixed Design

• • Definition

  • Pros and Cons

Explore More Topics:

• A Walk Through the History of CAD

• Is The Metric System Actually Better?

• Laser Cutter Materials

Explore More Tutorials, Tools, and Techniques:

• More Fusion 360 tutorials: List 1 - List 2 - List 3

• Making sketches from images in Fusion 360

• How to insert DXF files in Fusion 360

• Inkscape Tutorials: overview - Bezier(1) and (2) - Living Hinge

• PNG to DXF: Online Tool - Inkscape trace bitmap

• Nesting Software: svgnest - deepnest

• Joints in Action: enclosures - lacing and assemblies

• slicer