Reefs Reimagined: 3D Printing the Effects of Tsunamis on Coral

Lauren Mukavitz ‘27: In the Makerspace taking the supports off my finished models

Lauren Mukavitz ‘27: In the Makerspace taking the supports off my finished models

When most people think about coral reef degradation, they often think about bleaching and the effects of climate change. However, coral faces another danger that is hardly talked about—tsunamis. Coral reefs have a unique structure that increases the friction a tsunami encounters on its way to the shore, slowing down the wave and mitigating damage. However, the intense forces during a tsunami can be extremely damaging and can destroy entire reefs. To better understand this impact, I embarked on a project for my class Geologic Hazards with Mike Hudak, Assistant Professor of Geosciences, to model coral before and after a tsunami.

Replicating Tsunami Damaged Coral

First, I created an undamaged model that represented a small colony of coral polyps before a tsunami event. I used Ultimaker Cura to design a 3D model of the coral. Next, I wanted to simulate the damage caused by a tsunami. After struggling to find existing methods for modeling tsunami forces on coral, I teamed up with the David Keiser-Clark, Makerspace Program Manager, Elena Sore, Makerspace Student Worker, and Jason Mativi, Science Shop Instrumentation Engineer, to use SolidWorks, a 3D CAD program. We applied a nonlinear analysis with 0.3 bar (or 3E3 N/m^2) of pressure, the estimated force an average piece of coral experiences during a tsunami, to the undamaged model and let SolidWorks create a “deformed” model for us. It took the software approximately four hours to render these forces to the 3D model.

Left: Original coral model; Right: Same model but deformed using SolidWorks to simulate tsunami forces

Left: Original coral 3D model; Right: Same model but deformed using SolidWorks to simulate tsunami forces

The successful PLA print -- Stonefil was not a fan of my design

The successful PLA print — Stonefil was not a fan of my design

Then I had both models printed at the Makerspace. Initially, we tried using Stonefil PLA, a filament that would approximately mimic coral’s composition with its half PLA (a polyester typically derived from fermented plant starch, such as corn, cassava, sugarcane, or sugar beet pulp) and half ceramic powder. However, the model was too intricate for the material, resulting in a messy and unusable print. We ended up using standard PLA for the final models, which, while less accurate in texture, allowed us to proceed with the physical representation. To simulate sediment damage, I took the “deformed” model to the science shop and used a sandblaster. Unfortunately, the PLA was too strong, and the glass beads in the sandblaster didn’t deform as expected. So, we resorted to breaking the model by hand to represent the kind of physical damage coral might endure during a tsunami.

My models are only approximations of the damage coral sustains during tsunamis. The exact forces on coral polyps during these events are unique and complex, making accurate modeling challenging.

Next Steps

The first step to creating a more accurate model would be refining the methods to determine the necessary forces and coefficients. Then, we could use a 3D CAD program like SolidWorks for a more precise analysis. Additionally, applying post-processing techniques to the 3D printed models, such as using adhesives and texturing materials, could make the PLA models physically look-and-feel more like real coral, enhancing their realism.

Creating more accurate models provides a deeper understanding of the interactions between coral reefs and tsunamis, helping us plan better for these events. This knowledge can guide conservation efforts, inform disaster preparedness strategies, and contribute to the broader field of marine biology. As better models are developed, we move closer to mitigating the devastating impacts of natural disasters on vital ecosystems like coral reefs.

Postscript (August 16, 2024)

See related CNN article: Why this scientist is leaning on surfers, skaters and artists to protect the ocean – “Cliff Kapono is a Native Hawaiian pro surfer and chemist in a race to save the ocean he loves. He co-founded The Mega Lab, a science research group that welcomes anyone (no degree required!) who can help them develop technology and raise awareness about dying coral reefs.”

Postscript (September 9, 2024)

See related CNN article: See the technique that could help save the Great Barrier Reef – “Researchers in Australia are testing a technique called ‘coral seeding’ [that utilizes 3S printers] to help the Great Barrier Reef recover from the effects of climate change.”

The Lincoln Logs: Printing for the WCMA’s Emancipation Exhibition

Introduction: 

WCMA’s “Emancipation: The Unfinished Project of Liberation” exhibit

“Emancipation” exhibit

My most recent Makerspace academic project was assisting Beth Fischer, Assistant Curator of Digital Learning and Research for the Williams College Museum of Art. My task was to 3D print replicas of two sculptures of President Lincoln—Sarah Fisher Ames’ bust of Lincoln and the iconic Abraham Lincoln Life Mask by Clark Mill—as part of the WCMA’s “Emancipation: The Unfinished Project of Liberation” exhibits. These two models complement the work of Hugh Hayden, also present at Emancipation, who incorporates PLA prints into his artistic process. The exhibit emphasizes 3D printing as a relatively accessible medium for creativity and showcases different ways it can assist other styles of art, particularly molds.

Setup 

The two photogrammetry-based 3D models were gorgeous. They defined every ridge, bump, and strand of hair on Lincoln’s head while carrying the texture of the clay, but it was this beauty that posed a challenge. The multidimensional texture in clay is hard to depict using horizontal layers of filament, which is how 3D printers print. Although not a solution, a remedy to this problem was using a hybrid filament – part ceramic and part PLA. Although this filament can’t recreate the vertical complexity of a sculpted model’s texture, it provides a smoother, heavier finish that better resembles the original material. 

We had some leftover StoneFil filament from a previous project, but we knew we would need more to complete both prints. The question was how much more. We did not know how much filament remained on the spools and there was no specific size requested – simply that the two models remain proportional and be as large as possible. 

Naturally, as a math major, I took this as a challenge to maximize the size we could print with only one additional spool of filament. First, I printed two smaller models, noted their xyz scaling, and measured the distance from the nose to the chin. I then used those measurements to find the scale between the height of one and the length of the other. Then, given that scaling, I noted the estimated combined length of the models at a few different sizes and found the factor at which the necessary filament would scale in comparison to the size. In theory, I could approximate the maximum print size given the length of the filament we had left and the spool arriving soon. There was only one problem – we didn’t know how much filament we had. We could weigh the filament, but any statement on the spool-to-filament proportion would’ve been guesswork. 

That was when another Makerspace student worker, Elena Sore, had an idea to create a reference guide for the weight of empty filament spools. We use a variety of brands of filament, and each has a different sized spool. Now, when we finish a spool, we weigh it and enter it into a spreadsheet, allowing us to measure the amount of filament remaining on any given spool by subtracting the spool from the overall weight. 

Printing and Troubleshooting

The final bust with its supports still attached

The final bust with its supports still attached

The time came to print the models. I had decided on the heights 140mm and 93.15, which would give us just enough filament to print both models with enough to spare to be able to still print one more, just in case of failure. I sliced and started the print of the bust and 20 hours later, it came out well. There were a few small holes that indicated mild under-extrusion, but they were not too distracting and the WCMA was interested in showcasing the uniqueness of 3-D prints, so I was perfectly content with the model. 

The second print was not as fortunate. Externally, it looked fine, except the under-extrusion was more visible than the first model. Before removing the model from the plate, I started googling remedies for under-extrusion because I was concerned that I didn’t have enough filament to endure another failure. I recalibrated the printer, increased the nozzle temperature, slightly decreased the printing speed, and ran another mini model with ordinary PLA. It came out perfectly – and that worried me because I was nervous that the problem was with the ceramic filament, which was a requirement for the project. Eventually, I stumbled onto a solution by turning the StoneFil model upside down to examine the supports, and to my shock, I found that they were completely “spaghettified”. The supports had completely failed and were just a mess of tangled filament. I was impressed that the print had managed to build at all. 

The under-extrusion was far more noticeable on the first print of the mask than the bust.

The under-extrusion was far more noticeable on the first print of the mask than the bust.

Exhibition: “Feel free to pick up and touch these reduced-scale 3D prints of Abraham Lincoln!”

Exhibition: “Feel free to pick up and touch these reduced-scale 3D prints of Abraham Lincoln!”

I spent some time in different slicing softwares, trying to optimize the supports. It took (admittedly longer than it should have) to realize that with supports as dense as the model requested, this was a rare case where it would be more filament-efficient and less failure-prone to fill the space underneath the mask with infill, instead of supports. This was the solution we went with, and the bust printed perfectly.

While weighing the options for the final print, David Keiser-Clark, Makerspace Program Manager, and I brainstormed ways of filling in the holes caused by under-extrusion. Our favorite idea, and the only experiment we ran, was using a heat gun to melt a tiny bit of StoneFil filament into the hole and then sand down the excess. It was good in theory, and fun to try, but not entirely effective because it looked like a visible patch. This is because 3D printing filament solidifies incredibly fast after cooling, and we would have needed to either pour a liquid into the hold and/or do a tremendous amount of sanding afterward.

Conclusion

Coincidentally, as the final prints started, I again fell very ill and had to return home for the week and did not get to hand off the pieces. However, I did get the chance to go to the Emancipation exhibit and see the final results. The space itself was a moving experience, and I would strongly encourage anybody to visit or read about the exhibition and its incorporation of 3D printing. This was a fun project to complete during Winter Study, and I got the chance to answer a lot of looming questions about 3D printing during it. I learned a lot about the balance of layer height, print speed, and temperature, I’m excited to see what else we can do with our filament data log, and melting PLA with the heat gun was so much fun that I may try to find a way to make it practical. Although, I must admit, my favorite part of this project is the little Lincoln that found himself a home in my dorm.

An early, miniature prototype that now adorns my desk as a reminder of my work on this WCMA project!

An early, miniature prototype that now adorns my desk as a reminder of my work on this WCMA project!

Using Clay Based Filaments to Create 3d-Prints

This is an extension of the WCMA artist project. 

At this point, all of the 3d-prints for the Williams College Museum of Art (WCMA) have been in PLA plastic filament. Creating them in plastic was relatively inexpensive, convenient (as we already had that filament on hand), and gave a good enough visual representation of what the pieces looked like. 

Now that we now have access to a pottery clay-based filament the 3d-prints can now be created using the new filament type. As the pieces cannot be held by the average person creating models using stone based filament gives more accurate information on the artifacts weight and texture.

Our current machines have brass nozzles which are not suitable for the more textured pottery clay based filament. As a result, the brass nozzle needs to be removed and replaced hardened steel nozzle. 

Rebuilding the Prusa MK3S

Rebuilding the Prusa MK3S

Once the hardened nozzle was installed, the printer was recalibrated to account for any thing that might have changed when it was taken apart. The seated deity was printed as an initial test of the filament because it had the least amount of problems when printing in PLA. It was printed at 0.15 mm quality with a 15% infill and supports were generated everywhere. 

Printing with the Prusa MK3S

Printing with the Prusa MK3S

These are the results. 

Leah Williams 3D printed this using clay filament for Dr. Beatriz Cortez.

Leah Williams 3D printed this using clay filament for Dr. Beatriz Cortez.

Leah Williams 3D printed this using clay filament for Dr. Beatriz Cortez.

Leah Williams 3D printed this using clay filament for Dr. Beatriz Cortez.