CAD/CAM Training

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Computer Aided Design & Computer Aided Machining (#computer-aided-design on Slack)

This class teaches the basics of computer aided manufacturing using Fusion360. Fusion 360 for personal use is basically the only all-in-one design and manufacturing suite so we use it extensively. This class is a heavily recommended but technically optional prerequisite to the CNC Router Authorization class. If you’ve never used a CNC machine before then please take this class first.

Get Fusion 360 for personal use here! Fusion 360 for Personal Use — Have it installed and ready to go before class.

Homework Videos (Watch before signing up for class)

  1. What is a CNC machine, and what is gcode
  2. Intro to Fusion, Timeline, Environment Tree, User Preferences
  3. Modeling

Training Checklist / Class Notes

  1. What is CAD/CAM/CNC?
    1. How smart are CNC Machines?
  2. Why Fusion
    1. Parametric (e.g. Solidworks, Fusion) vs Direct or Mesh Modeling (e.g. Sketchup, Blender)
    2. All-in-One Workspace
  3. Similar to what we’re trying to achieve: Video (We are milling a square with “DENHAC” cut into it.

CAD

  1. Modeling Workflow
    1. Sketch -> Features -> Parts/Assemblies (advanced) -> Machining (CAM)
    2. Knowing where sketch elements end up in 3D Space
  2. Calipers 101 (Outside, Inside, Depth, Step measurements)
  3. Sketching (2D)
    1. Dimensioning, Fully Defined geometry
    2. Constraints
    3. Construction Lines
  4. Features (3D)
    1. Extrude Tool
    2. Operations (New body, Join, Cut, Intersect)
  5. Analysis Tools (Sections, etc)
  6. Exporting/Saving to .F3D

CAM

  1. Tool Library — Endmills
    1. Fusion Libraries, JSON Imports
    2. Adding endmills to your project
      1. Drag and Drop 1/8″ Flat Endmill as an example to edit — defaults don’t match the tools we have in the space
    3. Endmills
      1. Endmills are “consumable”, intended to break first
      2. Different endmill types and qualities
      3. Endmills are NOT drill bits!
      4. Anatomy of endmills (walkthrough, editing tools in Fusion)
        1. Tips and Cutting surfaces
        2. Flutes
          1. Number of flutes
          2. Upcut/downcut/compression bits, depends on material and cuts (e.g. compression for plywood)
        3. Meassurements
          1. Diameter
          2. Flute length
          3. Shoulder length (actual measurement Fusion uses)
          4. Rule of thumb: mill down to half of max cutting depth
      5. Feeds and Speeds
        1. Safety: Min/Max speed of Shapeoko (8000RPM/24000RPM). Drill bits max out at 3000RPM. Do NOT put drill bits in a CNC router!!!
        2. Values to tweak in fusion: spindle speed and feed per tooth (aka chip load)
        3. Choosing feeds and speeds (“vibes”, sound, depends on material)
      6. <Insert “official” tutorial endmill settings here for reference>
  2. Setups
    1. Stock Selection
      1. Relative or Fixed size box
      2. “fit to model” will treat cuts as already done in stock
    2. Machine Selection (optional)
    3. Work Coordinate System
      1. Z is up in Shapeoko/Nomad
      2. Axes can be different from model
      3. BitZero: consider how this is placed to pick an origin
    4. Multiple setups for parts and two-sided machining
  3. Toolpaths
    1. 2D/3D Operations
    2. Adaptive/Pocket
    3. Heights
      1. When cutting all the way through your part, you only want to mill 1 or 2 millimeters into the spoil board to avoid onion skin, milling too far into the spoil board can wear down the machine though (please, PLEASE do not hit the aluminum if you can help it)
    4. Climb vs Conventional Setting
      1. Conventional usually better for our hobby-grade machines with no backlash compensation
    5. Other Settings:
      1. Stock to leave
      2. Maximum stepdown
      3. Rest machining
      4. Ramping (how Fusion “drills in” to stock)
  4. Simulation
    1. Display/Visibility Settings
    2. Color Coding for remaining stock
    3. Timeline, multiple operation color coding, warnings
  5. Export
    1. Add Carbide GRBL Profile from Fusion Library
    2. Exporting to //dennas for easy loading
    3. Limitations of the free license (travel speed, tool changes) — Pro license in fishbowl
  6. `#computer-aided-design` on Slack for help and community!

References

Table of Contents