I believe the best way for children in grade 2~4 to learn 3D printing is to teach them how to print out their own sketches. Although Tinkercad already provides users with Scribble, an easy-to-use 3D CAD design tool, what is lost when children use a computer or tablet to paint is the feeling they get only from hand-drawn sketches. The following is how we print out children’s drawings through 3D technology. The idea came from a Youtube channel of a famous American Maker–I Like To Make Stuff
1. Scan and take photos of the original drawing when you are capturing the originals.
Try to avoid shadows and perspective distortion. It is recommended to use a scanner or the built-in document scanner in an iPhone to get the best copy result.
2. Convert images to vectors via Illustrator. The better processed the originals are, the higher threshold value would be available.
Different preset settings offer different results based on the styles of originals. Generally, default template would do just fine. You can also try different themes, such as sketched art, silhouettes, and line art, which offer better results. Don’t forget to use an outline instead of view when you are building the trace.
This process is where you keep the outline of the original, so that every trace from the original could be copied. Therefore, it is recommended to set different presets and threshold values for every drawing respectively, in order to better restore the drawing.
3. Smooth out the image after a trace.
After all the Image Trace settings are done, you can expand the image trace. After that, remove the unneeded elements. If there are paths that are not closed, use the fountain pen to trace the shapes.
Below is a Before & After comparison. If the main outline is simple, the patterns with closed trace can be kept for partial extension or cutting if needed.
4. Save as an SVP or DXF file after editing.
Tinkercad can only read SVG files, while Fusion 360 can read both SVG and DXF. However, when SVG files are imported into Fusion 360, some measurements may be reset and therefore require calibration, especially when you are making a 1:1 copy.
5. Import the file into Fusion 360.
You may have problems importing files with complicated patterns using Tinkercad. In addition, partial extension of a trace requires tools in Fusion 360, which is mostly handled by teachers in the first place. If the lines of the drawing are too thin, users can offset more than one line using the thicken command, so that the trace can be better restored during 3D printing.
6. Export STL for Tinkercad. （optional）
If the children would like to work on their own, you can export the draft as an STL file and import it into Tinkercad, so that children can work from a tablet or computer. In general, children can add some geometric patterns to the third axis in 3D space in addition to the original 2D patterns. This can be done through grouping or ungrouping objects, which will make the effect of 3D printing even more substantial.
7. 3D Printing
When everything is in place, all you need to do is print! *Another project being printed（not mentioned above）.
During the process, although the technology is not hard to understand, the operation is still trivial. Students from the middle and lower grades of primary schools may not be familiar with the measurements and CAD technology, so I believe this course is quite suitable for students who learn entry-level 3D printing.
Tinkercad is very intuitive, making it easier for children to visualize their ideas. Most importantly, children can really hold a product printed from their drawing in hands, which, I believe, is the best way to spark their interest in technology！