Wildcard Week
Metal Fabrication Exploration
For Wildcard Week, I wanted to try digital fabrication techniques that aren’t part of our usual workflow — methods that are powerful, precise, and industrial-grade. This led me to metal laser cutting and waterjet cutting, both of which are advanced subtractive manufacturing processes.
This week was as much about curiosity as it was about learning — from making a custom nameplate, experimenting with kirigami in metal, to designing and fabricating a carambit knife, a design I’ve admired since childhood.
Metal Laser Cutting
Project 1: Personalized Nameplate
Material Used: 0.5 mm Zinc Alloy Sheet
Machine: Fiber Laser Cutter
Design Process:
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Software: I utilized vector design software to create a nameplate featuring my name in a stylized font.
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File Preparation: The design was exported in DXF format, compatible with the laser cutter's software.
Machine Used:
We used a fiber laser cutter, which is designed for cutting reflective metals such as aluminum, brass, copper, and zinc alloys. The laser beam is generated using a fiber-optic laser source and focused using a lens to a tiny spot (as small as 0.01 mm), resulting in a very high energy density.
Cutting Process:
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Machine Setup: The zinc alloy sheet was securely placed on the machine bed.
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Parameter Settings: The laser cutter was configured with optimal power and speed settings suitable for 0.5 mm zinc alloy.
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Execution: The laser precisely followed the design path, resulting in a clean and accurate cut.
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The zinc sheet was clamped to the honeycomb bed to avoid movement or vibration during cutting.
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The laser head was manually or automatically focused to the surface of the metal using a distance gauge (some machines have auto-focus).
4) Parameter Tuning:
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Power: Around 60–80% (depending on machine capability).
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Speed: Medium speed (~10–20 mm/s) for cutting thin metal.
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Frequency & Duty Cycle: Adjusted to minimize burring and optimize cut quality.
5) Cutting: The laser follows the path, vaporizing the metal precisely. Assist gas (typically nitrogen or oxygen) is used to blow away molten metal and reduce oxidation.
Insight: Metal kirigami is possible — but it requires smart joint design and understanding of the metal’s ductility.
Outcome:
The finished nameplate showcased sharp edges and a professional finish, demonstrating the laser cutter's capability to handle intricate designs on metal surfaces.
Project 2: Metal Kirigami Experiment
Concept:
Inspired by the art of kirigami, I aimed to translate this paper-folding technique into metal, testing the flexibility and formability of thin metal sheets.
Design Process:
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Pattern Creation: A geometric pattern was designed to allow for folding and bending post-cutting.
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File Preparation: The pattern was exported in a format compatible with the laser cutter.
Cutting and Forming Process:
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Cutting: The pattern was laser-cut into the 0.5 mm zinc alloy sheet.
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Forming: Post-cutting, the metal was manually bent along the designed lines to achieve the desired three-dimensional form.
Challenges and Learnings:
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Material Behavior: Unlike paper, metal has limited flexibility, making precise folds challenging.
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Tool Limitations: The laser cutter could not perform partial-depth cuts, necessitating full cuts and manual bending.
Outcome:
The experiment resulted in a unique metal structure that, while not as flexible as its paper counterpart, opened avenues for exploring metal in artistic applications.
Waterjet Cutting
What I did:
Design and fabricate a carambit knife using abrasive waterjet cutting.
Machine Used:
A high-pressure abrasive waterjet cutting machine. This machine uses a jet of water mixed with garnet abrasive to cut through virtually any material, including mild steel, stainless steel, aluminum, and more.
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Typical Pressure: 50,000–60,000 psi (pounds per square inch)
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Abrasive: Garnet particles (80 mesh commonly used)
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No Heat-Affected Zone (HAZ): Because it's a cold cutting process, there’s no structural damage or deformation.
Designing a Carambit Knife
1) Design: I designed the carambit knife in CAD software in Illustrator , focusing on its iconic curved blade, ergonomic handle, and finger ring.
2) Material Selection: Mild steel (approximately 3–5 mm thick). A good balance of machinability and strength for a prototype.
3) G-Code Conversion: The CAD file was exported as DXF and converted to machine code using CAM software specific to the waterjet machine (e.g., FlowCAM or IGEMS).
4) Abrasive Jet Setup:
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The garnet is mixed into the water stream via a nozzle (orifice + mixing tube).
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The nozzle moves over the sheet using a gantry system, following the cut path.
5) Cutting:
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Waterjet pierces the material initially at a lower feed rate, then increases to optimal speed.
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The cut was extremely clean and accurate, even in tight curved areas like the carambit’s inner blade.
Fun Fact: Waterjets can cut up to 30 cm thick steel if needed. Their precision is such that they’re used in aerospace and medical industries!
Learnings & Reflections
1) Tool Mastery Requires Context – These machines aren’t plug-and-play. You must understand parameters like focus depth, power settings, abrasive flow, and material behavior.
2) Design for Metal Is Different – Sharp corners can cause stress concentration, and kerf compensation must be considered for accurate dimensions.
3) Precision Has a Cost – Both processes are expensive and require careful planning, but the finish and accuracy are unmatched.
4) Safety and Respect for Tools – These machines are industrial-grade — they demand caution and trained supervision.
5) Creativity Beyond Materials – Trying kirigami with metal expanded my thinking on combining art and engineering.