CAD/CAM

TO SAVE YOUR TIME: BEFORE CAM-MING A COMPLEX PART GET A CAM PLAN THROUGH A CONSULTATION TO ENSURE WE HAVE THE MACHINES AND WORKHOLDING TO MAKE IT.

Please check any files for updated versions on a regular basis as we regularly improve and fix bugs in them.

Overview:

CAD (Computer Aided Design): Software that allows you to draw a part in 3D space to better visualize features and geometry.

CAM (Computer Aided Manufacturing): Software that allows you to develop a toolpath to manufacture your part in a CNC machine.

Post Processor: A specialized file that converts the toolpath generated by the CAM software to code that a specific Make and Model of machine can understand.

CAD/CAM at the Bechtel Center

The Bechtel Center fully supports the use of Autodesk Fusion 360. Although you are expected to learn CAD and CAM on your own (scroll down for learning links), Bechtel Center mentors will be able to answer any specific questions. Autodesk Inventor HSM can also be used, but mentors can provide less knowledge and support for problems you may have.

Reference the below CAD tips to design your part for ease of manufacturing. Redesign your part if necessary.

Download the Bechtel Center Tool Library and Post Processors from the respective subpages, and install following the instructions accompanying the files.

Consult a Bechtel Center mentor to determine a CAM strategy. Parts can be created on the 3 axis mill, 5 axis mill (navigate to the Dovetail Setup subpage to create your workholding geometry), gantry, ST20 lathe, or ST20Y lathe. Create your CAM and verify with a mentor that it is correct. When ready, upload to the fileshare server.

Reserve machine time for your project using the project website. Reserve more time than you think you will need, as setting up machines takes a long time and mistakes in machining can occur that will take time to correct.

Design Tips for Manufacturability

  • Size your part for stock that is available in the stock room.
  • Size features in your part to accommodate standard tools - both radius and depth. Standard tools are in the Bechtel Center tool libraries.
  • Consider fixturing - ease of holding your part in a vise (flat sides, less than 7.5" wide, minimize ratio of height to clamping area).
  • Minimize the number of setups you will need to manufacture your part - minimize the number of sides with features.
  • Design wall height and pocket depth to be less than 90% of the flute length of the tool you will use.
  • Design wall and floor thicknesses to be greater than 0.2", or have a 5:1 ratio between height and thickness.
  • Design holes for standard size drills and use a ratio of less than 3:1 or 5:1 for depth to diameter. Ensure holes have flat entry and exit surfaces.
  • For tapping, avoid tapping blind holes. Design for standard tap sizes.
  • Fillets:
    • Floor fillets: Match with tooling if floor fillets are necessary, avoid if possible.
    • Interior corner fillets: Will always be present. Should be at least 1.25 times the tool radius.
    • Exterior corner fillets: Avoid sharp corners. Larger fillets are better.
  • Minimize material removal.

For more detail, please reference this video on designing parts for CNC milling.

CAD/CAM Learning Resources

The Bechtel Center is not able to fully teach CAD and CAM. If you have never worked with one or both of these manufacturing methods, please navigate to the below (free) resources, or find others to learn. Scroll down for our tips on designing for manufacturability.

Autodesk Fusion 360 courses for CAD and CAM at many different levels

Titans of CNC courses for CAD and CAM at many different levels

If you are participating in CAM training at the Bechtel Center, please download the BIDC_CAM_TRAINING_TOOLS and install using the tool library installation instructions on the Tool Library Files subpage.