When I first started teaching I got offered an incredible budget to set up my STEM program. The only caveat was that I buy a 3D printer with some of the money. The challenge however, was that I’d never heard 3D printing before, let alone how to design a 3D Printing Lesson. What I needed was something simple, engaging, adaptable, and quick to learn. I did internet research, and though there are some good resources now, at the time there really weren’t. Instead I designed my own curriculum for grade 7 & 8. After twelve or so refinements I came up with the 3D Printing Lesson you’re about to read.
The below 3D Printing Lesson assumes that you already know how to use your 3D printer, and are familiar with model rocketry in general. As of this posting, I don’t have a recommendation for a 3D printer. That said, Make Magazine does a great annual article evaluating what’s out there. Depending on which make & model printer you buy, training may be available from the manufacturer. Alternatively there are lots of how to articles, and videos online. One day I hope to buy a kit, and make my own printer. When/if that happens I will document the process. If you are unfamiliar with Model Rocketry though, I have good news. Why you should use model rocketry is covered here, and Lesson 1 in the series is here. This lesson will refer back to lesson 1 often so, give it a read if you haven’t already.
In case you haven’t read my other Lesson posts it is worth noting that my style of writing a lesson plan isn’t what you may be used to. I write out the plan in a manner that is meaningful to me as a teacher. The first thing I typically need to know is what materials I need, followed by what to teach, followed by how to teach it, and finally the applicable standards. Here we go!
3D Printing Lesson: Introduction.
In this lesson students design several model rocket nose cones based on established shapes using computer aided design software. Students print out each nose cone, equip a model rocket with it, launch the rocket, and record the data. The same rocket body is used for each launch to protect the integrity of the data. This lesson is designed for use in grades 7 or 8, and takes approximately 1 academic quarter the way I teach it.
I have my students build rockets from scratch, but if you use kits this lesson could take less time. This lesson could also take less time if you give students measurements to work with. I ask my students to develop size specs on their own. This lesson could certainly be used as a performance task for performance based assessment. I also teach this lesson along with Rocketry Lesson 1 as opposed to separating them in order to save time.
3D Printing Lesson: Materials.
- 3D Printer & Supplies.
- Rocketry Supplies (see Lesson 1).
- A computer (Chromebooks work fine), or tablet for each student.
3D Printing Lesson: What to Teach.
- Computer Aided Design.
- 3D printing.
- The Iterative Design Process.
- The Use of Data in Design Decisions.
- Everything from Rocketry Lesson 1.
3D Printing Lesson: How to Teach
If you are using kits, begin with constructing the kits. If you are doing a from scratch build to a certain set of instructions like I do, you can start with that. In either case, while construction is happening, I go over the Parts of a Model rocket from lesson 1, but as I am having my students design the nose cone for the model rocket, I go into greater detail on the nose cone as shown below.
I apologize for the quality of the drawing, clearly I teach Tech Ed not Art. Since we are creating the nose cones we need to have a shared vocabulary when discussing a given design. When we get to the actual design phase I will give my students some specifications for measurements, but for now they just need to know what the various parts are called.
Baseline Launch or CAD?
Once you have a shared vocabulary established, and rockets assembled you can go one of two ways. You could put some standard nose cones on the rockets, have a launch, and record data for a baseline. I take the other tack, which is to begin with the use of the Computer Aided Design tool. Great News! If you use the tool I use (which is free, web based, and functions well on Chrombooks) called TinkerCad, it comes with a whole suite of fantastic tutorials that guide your students through the various aspects of the software. For this 3D printing lesson you can allow students time in class to work through the tutorials, assign it as homework, or do a combination of the two.
I have my students do the tutorials in Basics, Accessories, Gadgets, and Miniatures. One word of caution here, if your students are under the age of 13 setting up an account takes parental approval. The site uses a question about birth date to verify age when an account is set up, but doesn’t do any other type verification.
Once you & your students have established a shared vocabulary, learned how to use CAD software, and have built rockets you can begin to design nose cones. Prior to beginning the actual design of their first nose cone I ask my students to research model rocket nose cone shapes. I am trying to get them to find conical, ogive, parabolic, and blunt shapes. At this point I ask them to make a prediction about which nose cone will give the rocket the highest altitude. Once they have done their research I give my students a set of digital calipers, and have them get the interior diameter of their rocket air-frame. The should also measure the exterior diameter. Their first assignment is to design a Conical Nose Cone.
Nose Cone Design Requirements
- The nose cone must fit snugly into the rocket air-frame.
- The nose cone must have a shock cord mount.
- The height of the cone is twice the exterior diameter of the body tube (2D).
- The total height of the full nose cone including body tube mount is three times the exterior diameter (3D).
- The shoulder will measure 2 millimeters.
In all likelihood, your students will need to go through 2-3 iterations just to get the nose cone to fit inside the air-frame correctly, and meet the specifications. Here is one I designed for the project. See the Pro Tips below to learn from my experience.
Design & Printing Pro Tips:
- Print the shock cord mount beside the cone & superglue it onto the bottom.
- Make an indent in the bottom of the cone for the shock cord mount to sit in.
- In your 3D printing Software, there should be an add feature to add several additional objects to your print, use it.
- If you follow this pro tip assign students a number or letter to have as a unique identifier such as the “X” on my example nose cone.
- Make certain to have your students name the files in a descriptive way.
- For instance, if the class is grade 7 quarter 1, the student’s name is John Smith, and the nose cone is conical I have them name the file: G7Q1ConicalNCJS.
- Teach students how to use the Align Tool in TinkerCad so you can have everything centered.
- Students will save themselves heartache if they fully understand the Ruler Tool in TinkerCad.
- For each design after the first they copy (Ctrl+C) & paste (Ctrl+V) their body tube, and shock cord mount assembly from the successful conical design. Those two features don;t change from cone to cone.
- When printing nose cones set the initial fill setting to 0.00%. This gives you a very light nose cone.
- You can expand this lesson by messing with the fill, and seeing how much the weight of the nose cone changes with the fill percentage. You can further expand it by seeing how much nose cone weight effects altitude.
Once you’ve got conical nose cones that fit snugly into the students rockets you’re ready to move on. Schedule a launch, launch rockets, collect data, and go over that data as a class. I go into more detail on both data collection, and expansions in Lesson 1. After the first launch move to a different nose cone shape, and do as many launches as you can. The more launches your class does, the more interesting your data will be. For comparison, the most launches I have achieved within a quarter was 3.
- All Standards covered in lesson 1.
- Future Tech from 3D printing.
- CAD introduction from TinkerCad.
- Additional math standards based on the calculations you have your students perform.
Expansion, Assessment, & Conclusion
I have expanded this lesson by complicating the nose cones in various ways. One good way to complicate the design of a nose cone includes eliminating the square shoulder in favor of a parabolic shoulder. One way to complicate the data, and analysis of a launch is to include meteorological data. The data can be further complicated by adding speed, and velocity calculations. This lesson really is almost infinitely expandable with a bit of creativity.
To assess this unit I have posed questions relating to a fictional rocket launch in short answer form. If you are working towards performance based assessment, you can give your students a design challenge with a goal of highest, or lowest altitude as an assessment.
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