2025 Summer Research | Reflection on Materials Used in the Spring Performance - CHI-CityTech/BSP-graphic-imagery GitHub Wiki

@ Sam Cheung

Overview:

In our department’s quest to develop durable and visually engaging Wayang-style puppets, we experimented with two primary prototype materials: chipboard and acrylic. Each material was selected based on availability and perceived advantages for laser cutting and detailed design.

Chipboard Prototypes

Overview:

Chipboard was chosen for initial prototypes due to its ready availability within the department. Its ease of processing on a laser cutter allowed rapid iteration on shape, scale, and general appearance. However, after several test trials, we identified both strengths and weaknesses.

Advantages:

  • Abundant Supply: Our department maintains a large stock of chipboard, ensuring that prototype iterations could proceed without material shortages. (ITS FREE!!!)

  • Ease of Laser Cutting: Chipboard cuts cleanly and quickly on our existing laser cutter, enabling efficient fabrication of complex silhouettes and basic structural components.

  • Concept-Scale Testing: The material’s low cost and rapid turnaround permitted us to validate conceptual designs—testing character proportions, joint placements, and overall puppet scale—without significant investment.

  • Flexibility for Simple Structures: Although more delicate than traditional leather, chipboard remains sufficiently flexible for basic articulations, provided that design constraints (e.g., minimal perforations near stress points) are observed.

Disadvantages:

  • Structural Weakness at Joints and Holes: Limbs located adjacent to perforations or axis joints frequently cracked or tore after repeated manipulation.

  • Wear-and-Tear over Performances: Decorative holes placed near stress points led to accelerated degradation. Repeated use in shows necessitated extensive repair work between performances, including patching torn sections or reattaching detached limbs.

  • Design Constraints Limit Aesthetics: To mitigate breakage, we reduced decorative perforations and avoided intricate cutouts near joints. These design compromises limited the visual richness typical of traditional Wayang puppets.

  • Material Fatigue and Bending: Under routine handling, chipboard warped or bent, rendering puppets extra fragile and requiring careful storage and transport.

Acrylic Prototypes:

Overview:

After identifying chipboard’s limitations, we transitioned to acrylic for subsequent prototypes. Acrylic offers greater rigidity and the potential for color integration via backlighting or translucent gels. The material’s properties support more complex designs and attachments for mechanical articulation.

Advantages:

  • Support for Complex Designs: Acrylic’s rigidity allows for intricate cutouts—especially decorative patterns that chipboard could not reliably sustain.

  • Color Enhancement: By applying translucent gels behind cutouts, acrylic puppets can cast colored projections onto the screen, enhancing visual storytelling.

  • Reinforced Structural Backing: Thicker or layered acrylic sheets can accommodate mechanical joints and mounting points for automated movement systems, reducing the risk of breakage under stress.

  • Compatibility with Laser Cutting: Provided the correct thickness is selected (commonly 2 mm to 3 mm), acrylic cuts cleanly on our laser cutter. Using the architecture-grade cutter ensures adequate ventilation, as acrylic emits an unpleasant odor when cut.

  • Mechanical Integration: The material’s strength allows secure attachment of rods, hinges, and servo mounts for future puppet automation.

Disadvantages

  • Increased Weight: Acrylic is considerably heavier than chipboard, making larger puppets cumbersome to manipulate and transport. This limits its practicality for full‐scale or frequently used puppets.

  • Brittleness under High-Stress Conditions: While more durable than chipboard, acrylic can crack or shatter if subjected to excessive bending or impact—particularly at thin cross‐sections or detailed filigree.

  • Unsuitability for Extended Screen Time: For characters that appear briefly or in smaller formats, acrylic is acceptable. However, long-duration on-screen performances may fatigue puppeteers due to increased weight and handling difficulty.

  • Dependency on Secondary Materials: To exhibit decorative holes effectively, acrylic prototypes often require a chipboard or paper backing to create contrast. This adds an extra fabrication step and can reintroduce some fragility from the chipboard layer.