Introduction to CAD, Engineering, and 3D Printing

Computer Aided Design (CAD) is used to build most products we have in our homes today, and lots of others too. Computers, televisions, cellphones, desks, chairs, toys, forks, plates, cups, cars, trucks, airplanes, spaceships... all are designed with CAD tools. CAD is a very big and complex topic, with many specialties and subfields, and you can spend an entire career as a CAD engineer. These projects are designed to give you a taste of a kind of CAD called parametric 3D modelling, which we can use to design useful 3D printed objects. You'll learn enough to be dangerous, and maybe you'll decide that you want to study this subject further, or even make a career of it.

The Project

In this project, you'll be designing a small, useful 3D-printed object in a parametric CAD system called Onshape. You'll learn basic modelling in Onshape, and then each team in your class will design the same thing (either a chip clip, a cell phone stand, a salt shaker, or a cord management device) so you can compare your results. Once you're done, the STEM Explorer team will 3D print your designs and mail the finished products to your school so you can see how well they work. When you're all done, your class will vote on the best design for your teacher to submit to the STEM Explorer team for inclusion on the All-Star Engineers page.

The Standards

This project is designed to meet Michigan science standards MS-ETS1-1, MS-ETS1-2, and MS-ETS1-3, and to meet ISTE standards 1a, 2a, 2b, and 2d. For more information, you can read our standards summary document, Michigan's standards document, and the ISTE's standards page.

The Rubric

When your teacher grades your project, and when you evaluate your classmates' work to vote on the best design, you should all try to apply the same standard. There are several important criteria for the best design, including not just how well it works, but also how durable it is (you don't want it to break while you're using it!), how easy it is to operate, and how much material it takes to build — more material means it costs more money to make! We've created a rubric you can use to judge how well your designs meet these criteria.

Important Links

• Onshape's website contains everything you need to do your CAD work, including of course the Onshape application.
• You'll also want to refer to our Onshape tutorial videos to help you learn how to make models. If possible, it's best if you watch all of them, but these ones are especially important:
  • Creating your Onshape account
  • Creating your first Onshape part
  • Onshape Part Studio Interface Tour
  • Fun with Sketches
  • Fun with Dimensions
  • Fillets, Chamfers, and You
  • Measuring Distance and Volume
  This one is also very important if your class is creating salt shakers:
  • Fun with Patterns
• If you're a teacher, you can get more information about the project from our summary presentation and sign your class up with our signup form.

Step By Step

1. The STEM Explorer team will give you an introductory lecture to start the project off, so you understand what you need to do. We'll try to do this live, either in person or over videoconference, but if we can't you can watch our prerecorded video version.
2. Once you've gotten started, you'll also need to follow along with our Onshape tutorials to learn the CAD basics you'll need to build your 3D-printed design.
3. Now, you're ready to start brainstorming. Your teacher should have told you what you'll be designing. At this point, it's time to discuss design ideas in your team, using whatever tools you like. When you're done, you should make a basic sketch of your design and turn it in to your teacher and to the STEM Explorer staff.
4. When you've finished your sketch, you should be ready to start modelling it in Onshape. You should create one document and then share it with everyone in your team, so that you can work on your design together with your teammates, and with your teacher and the STEM Explorer staff, so we can help you out if you get stuck.
5. When you're all done, you should create a final revision of your design in Onshape and tell your teacher and the STEM Explorer staff that it's ready for printing. The STEM Explorer team will load it into one of the STEM Explorer's busy 3D printers, get it printed out, and then mail it to your school. (This part might take a while, because 3D printers are pretty slow, and ours will probably be really busy.
6. Once you have your finished 3D printed design, it's time to test it! You'll need to make sure it works the way you intended, and it's also important to look at how durable it is, how easy it is to use, how much material you used, and other engineering criteria. You'll compare your test results to other teams' to see what they did.
7. After you've tested your design and compared it to your classmates' work, your whole class will take a vote on which one you think is the best. When you have a winner, your teacher will submit it to the STEM Explorer team, who will include it in the Engineering All-Stars page!