"Modeling Topography and Erosion with 3D Printing" is a project that will demonstrate the effect of river erosion on the Grand Canyon. This model will act as a visual aid for studying geography and earth science.
The included 3D printable files will allow students to create a scale terrain model of this region and all the accessories needed to simulate a water source.
By using rigid plastic PLA to print the Grand Canyon and water soluble PVA to print a River Valley that fits within, water poured through the river will dissolve the PVA and gradually expose the canyon underneath. During the experiment, participants will observe natural formations that will appear and identify geographic terms to understand how and why these structures come to be.
Update #1 - 4/12/2018: I have uploaded an experimental two-part mold for the PVA river, in case you would like to cast the river insert out of a different material (or from liquid PVA). This is still in the very early testing phase, so please use at your own risk. The mold has four mounting holes for standard M3 (x12mm or longer) bolts.
Feel free to share any images, videos, tips, tricks, or suggestions from your experiment and experience with the project!
Awards, Accolades, and Mentions
- Pinshape Create to Educate Lesson Plan Contest - 1st Place Winner
- Pinshape Featured Design - December 1, 2017
- Make Magazine Blog Article - December 18, 2017
- Cults 3D Selection - December 2017
- MatterHackers Minute - Create to Educate Design Challenge Review
Timelapse video here (and embedded at the bottom of the page):
Follow me on Instagram to see more of my cool stuff! :D
This lesson plan is written with an emphasis on the Common Core Science Standards for the state of Michigan. The guide follows classroom goals set by the "Science Course/Credit Requirements" document to engage student interest in STEM subjects.
The PDF guide includes a detailed print setting chart. The basic goal is to print the Grand Canyon in PLA with thick walls (3 perimeters or 1.2mm, 20% infill), and the River Valley in PVA that is completely solid to allow for proper erosion (100% infill). This will come out to around 60-70 grams of PLA and 30-35 grams of PVA.
Each brand of filament and machine is different, so make sure to use the recommended settings as a starting point and do plenty of tests before printing the final model. I have included the "testPiece_insertPVA.stl" file for small PVA prototype prints.
The Grand Canyon model was generated using Terrain2STL by Thatcher Chamberlin. I then used Blender 3D to make the custom PVA River Insert and the additional experiment parts.
If you have a dual or multi extrusion 3D printer, like the Ultimaker 3 or the Prusa i3 MK2/3 Multi Material, you can easily combine the PLA and PVA to print them simultaneously. If you do not have one of these, the models can still be printed using a single extruder. As long as your print bed is 160mm or longer, any printer will work.
All of the models have been tested and verified on my Prusa i3 MK2S.
Overview and Background
This project is possible due to the unique properties of PVA filament. PVA is the same material from which glue sticks are made. Most 3D printing hobbyists use this material as a dissolvable support structure for complex models. My concept proposes using it as a functional end product by leveraging the water solubility of PVA to demonstrate a natural process.
PVA has a similar extrusion temperature to PLA (180 - 200 ° C) and is easy to remove from plastic parts, making both materials a perfect match. PVA does absorb moisture from the air, so store the filament and finished 3D printed parts in sealed bags before and after the experiment.
Lesson Plan and Activity
To begin, download the included "Modeling Topography and Erosion with 3D Printing" PDF and STLs. Follow the instructions within the guide, which will take you through all the necessary steps and project information, including:
- Basics of 3D printing for students
- Process of obtaining terrain models online
- Printing the Grand Canyon, PVA River, and accessories
- Observing the model
- Documenting findings
- PLA Spool(s) (1kg) (Extra colors optional)
- PVA Spool (0.25kg - 0.75kg) (MatterHackers PVA, Ultimaker PVA, or Polydissolve S1)
- Soda Bottle (2 Liter)
- Box Cutter or Drill Bit
- Phillips Screwdriver
- Duct Tape
- Camera and Tripod (Timelapse optional)
- Sink or Bowl
- 3D Printing
- 3D Model Generation
1 to 2 Days (3D Printing) and Several Days to 1 Week (Erosion Experiment)