What is CAD/CAM and why should a Ham care?

Overview of process

  • CAD
    • Software to draw/design your model (2D or 3D)
    • Will leave you with some sort of picture/model file:
      • 2D: Vector file – NOT bitmap
        • Yes: SVG, DWG, possibly PDF
        • No: JPG, PNG, screenshot, scanned paper drawing…
          • At least not like that: can be traced, inspiration, etc.
      • 3D: SCAD, STEP, IGES, SLD*, F3D, etc.
      • PCB: Gerber (though you'll probably have a .BRD, .kicad_pcb, etc.)
    • Purpose of model: describe “outline” of what you've designed
      • Think home rendering
      • Tells us lots about what we want to build
        • “A panel of this by this, with a hole with this dimension here, and missing a square there with that dimension…”
        • Definition of shape and how everything is positioned relative to each other
      • No idea of how to actually build the model, just the (exact) shape.
        • Nothing about how to actually get a panel of that shape, or how to create those holes or missing squares…
  • CAM - Software to translate model into paths (cutting lines) - GCode
    • Often overlooked part of the process!
      • Not File/Print!
    • From home rendering to architectural building plans
      • Even detailed rendering doesn't care about (most) details!
        • Materials (studs, joists, wiring, plumbing, etc.)
        • Structure (How does the house stand up?)
        • Process (Need foundation, then framing, then surfaces, then finish)
        • Interference (Multiple items may try to occupy the same space!)
    • CAM not a generic process
      • Specific for each type of machine and process!
        • Additive:
          • 3D printer (plastic extrusion)
          • DMLS (metal sintering)
          • SLA/DLP (light/resin)
          • SLS (light/powder)
        • Subtractive
          • Flat (2D / 2.5D)
            • Router (tool-based)
            • Laser/Waterjet/Plasma/EDM (non-tool-based)
            • Rotational
              • Lathe
            • 3D (Extra DOF)
              • Mill
      • Each machine has specific details it needs beyond simple shape and dimensions
        • Specific path details
        • Machine capabilities/limitations
        • Material details
          • Speeds and limitations
          • Tooling details (size, shape, etc.)
            • Change the tool, literally change everything
    • At this point, presentation becomes much more use-case specific
      • Additive (3D Printer) much different than Subtractive (CNC Router)
        • Machine, material, techniques, limitations, etc.
    • My perspective: desktop CNC router in wood or PCB
      • 3D printing similar concepts but very different details
  • Purpose: to create detailed instructions how to build your model
    • Reflecting details of your tools and material as well as your model
  • Additive: Slicer
    • Effectively fill-in layer-by-layer
    • What is the footprint in this fraction of a millimeter layer? Draw it!
      • Not quite so simple: Overhangs, underhangs, support material, bonding
      • Other subtleties: direction of strength/shear,
  • GCode Sender - Software to take

CAD Options

  • 3D
    • Free as in freedom
      • OpenSCAD (For us wierdos)
      • FreeCAD (For power-user types)
      • Blender (For artistic/graphical types)
    • Free as in beer
      • TinkerCAD (For a simple start)
      • OnShape (Great for collaboration)
    • I've got a budget and I'm gonna use it
      • The pay-for versions of the free-as-in-beer…
      • Fusion360 (Low-end professional CAD)
      • SolidWorks/CATIA/UG (Why are you even listening right now?!?)
  • 2D
    • Resources:
    • Free as in freedom
      • Inkscape (For those used to graphics design over CAD)
      • QCAD (Includes some CAM functions as well)
      • LibreCAD (For power-user CAD types)
    • Free as in beer
      • NanoCAD (Legacy version is free but still needs yearly renewal)
      • SketchUp (For those who want easy)
    • I've got a budget and I'm gonna use it
      • The pay-for versions of the free-as-in-beer…
      • Adobe Illustrator (If you've got it, use it)