3D Scanning and Printing

This week was all about additive manufacturing, better known as 3D printing. Unlike traditional subtractive manufacturing, where material is carved away from a solid block (like CNC milling or laser cutting), additive manufacturing builds objects layer by layer, allowing for more complex and intricate designs.

Testing the 3D Printer

For our group task, we tested the design rules of our Creality K3 V3 3D printer. This involved printing test objects to evaluate the printer’s ability to handle overhangs, bridges, tolerances, and surface finishes.

Key Learnings from Testing

Overhangs & Bridges: The printer handled up to 45° overhangs without support, but steeper angles required additional structures. Tolerances & Fit: Best results for moving parts were achieved with 0.2mm to 0.4mm clearance. Surface Finish: PLA printed smoothly at 0.2mm layer height, though sanding was needed for a refined look.

These insights helped me fine-tune my individual project settings for better accuracy and print quality.

Spiderman Web Shooter

Why This Design?

I wanted to create something fun, interactive, and mechanically functional—so, I designed a Spiderman Web Shooter with a magnetic bullet dart. The design involves:

A curved wrist-mounted base for comfort.
A locking and launch system that shoots a dart when triggered.
A thread storage rod that allows smooth deployment when firing.
A magnetic bullet that sticks to metal surfaces, simulating web attachment.

This design could not be easily made subtractively, as traditional methods would struggle with:

Internal channels and enclosed spaces (needed for the launch system).
Complex curves (for wrist ergonomics).
Interlocking moving parts (that work as a single mechanism).

Step 1: Designing in Fusion 360

I started in Fusion 360, ensuring each part fit together correctly. Key features:

Curved Wrist Base: Comfortable fit with side brackets for a Velcro strap.
Firing Mechanism: A piston-like chamber with a spring-loaded trigger system.
Thread Storage Rod: Positioned for smooth unwinding when the bullet fires.
Magnetic Bullet: A hollow space for three neodymium magnets, allowing it to stick to metal.

Step 2: 3D Printing Process

Printer Settings

- Printer Used: Creality K3 V3

Material: PLA
Layer Height: 0.2mm
Infill: 20%
Supports: Required for overhangs (tree supports)
Print Speed: 80mm/s

Post-Processing & Assembly

After printing, I:

Removed supports with pliers.
Sanded rough edges for smooth movement.
Inserted magnets into the bullet cavity.
Installed the spring and locking system.
Threaded the web line onto the storage rod.

The final test was amazing—the bullet launched smoothly, the thread unwound properly, and the magnets worked as expected!