Having helped teach a large university class of over 70 students, I wanted to write down a few methods used to make the class a success to serve as a reference for myself in the future and also to help anyone who happens across this post.
Class Objectives
The objective was to teach students with no 3D design or 3D printing background how to build a 3D model of a product design sketch they developed in a previous class in SketchUp, set it up for 3D printing using slicer software (Cura, Colido), and use 3D printers (Ender 3, Ender 5, Colido 3.0) to print out their designs.
Projects also had to be prepared for presentation, with students using cardboard and other craft supplies to create a setting for their 3D printed model that helped illustrate its purpose and use.
Setting Up the Class
All 70+ students had their own sketches from their previous course. But the students were placed into 14 groups with 3-7 students in each group for the 3D design and 3D printing class.
The class was broken into 3 days:
- Day 1: Introducing, teaching, designing in SketchUp, and producing an STL file for 3D printing;
- Day 2: Preparing STL files in slicer software (Cura, Colido), and beginning 3D printing;
- Day 3: Finish 3D printing and preparing final presentations.
Teaching
Day 1
- Introduction: A very brief introduction was given (5-10 minutes) which included a demonstration of how to make a cube in SketchUp;
- Choosing a Design: Each group worked individually one-on-one with the lecturers to choose which of their designs they would attempt to design in SketchUp while other groups experimented with SketchUp's tools;
- Design Demonstration: After each group consulted with lecturers to choose a design, starting with group 1, each group came up one at a time to see their designs quickly built in SketchUp including an explanation of the tools needed to do so. They were then sent back to try on their own;
- Walk-Around: Once all 14 groups observed their demonstrations and were sent back to work on their own, lecturers walked around the class to spot check and assist students until their designs were complete;
- Converting to STL: Once groups were done with their designs, lecturers helped each group export their designs as STL files for 3D printing on Day 2.
Day 2
- Introducing Slicer Software: A very brief introduction of how to download, setup, and import STL files into slicer software was given to each group individually;
- Checking/Repairing STL Files: Each group attempted to import STL files into their respective slicer software and had it checked to see if it would print. Groups that had problems were assisted in repairing their models in SketchUp and re-exporting the files as STLs;
- 3D Printing: Once the each group had ther files ready to print, the class was moved into the 3D printing lab where projects began being printed.
Day 3
- Printing/Iterating: As prints came out, different issues arose regarding design outcomes students sought. Lecturers helped students revise SketchUp designs, adjust settings in slicer software, and taught them how to use the 3D printers;
- Presentations: As final prints finished, students began preparing presentation boards for their designs. A photography area with a backdrop was provided to take final images of the final presentations.
Miscellaneous
A few extra tips and tricks that will make it easier to wade through a large volume of projects, files, and designs include:
Viewing GCODE: Use notepad and open the GCODE file (make sure to select "all files" for formats you want notepad to open). This allows you to see the actual code, line-by-line and troubleshoot issues slicer software might not make apparent. It also allows you to double check settings like bed temperature, resolution, and infill.
Exporting STL Files: When using SketchUp, make sure that the option to "export selection only" is checked. Different wording may be used for this option from one version of SketchUp to the other. Some versions require an STL export plug-in (which requires a Trimble or Google account to download), while other versions can export via; File/Export/3D Model/Save as type/.stl.
There is an "Options..." box at the bottom of the export window where you can check an option for "Export Only Selection Set."
Class Prerequisites: The software is an obvious must. So is a quick and tried explanation/method of how to install software and plugins if students did not already do so.
More importantly, students must bring a mouse to use with their laptop/notebook computers. While you can technically make models in SketchUp using a trackpad/touchpad (and several groups did an amazing job doing just that), it is frustratingly inefficient and time-consuming.
Follow ProgressTH.org on Instagram here. We also put all of our 3D printed models online for free at Thingiverse.com here.
