Week 2

2D Design & Laser Cutting

Exploring computer-aided design (CAD), laser cutting tolerances, and press-fit construction kits.

I: Fusion Tutorial II: Household Objects III: Press-Fit Kit
01

Fusion 360 Tutorial

Learning the dexterity of parametric modeling.

Following Dr. Melenbrink's square demo to understand constraints and parametric history.

Step 1

1. Create 40x40mm square

Step 2

2. Offset -10mm & construction lines

Step 3

3. Mirror & Extrude 4mm

02

Modeling Household Objects

Reverse engineering physical objects into digital twins.

The iPhone Project

I chose to model an iPhone by first measuring critical dimensions: thickness, length, width, display area, and notch geometry using digital calipers.

  • Accurate corner radii
  • Button placement constraints
  • Camera bump extrusion
iPhone CAD
03

Press-Fit Construction Kit

Designing a modular kit that accounts for laser cutter kerf.

Attempt #1: The Hexagon

My first cut was a hexagonal gear mechanism intended to form spheres.

Failure Analysis: Excessive notches rendered the design un-attachable. The vertices interfered with connections, and I completely neglected to calculate the kerf (material burned away by the laser).

Hexagon Fail

Attempt #2: The Kerf Miscalculation

I measured the cardboard cutout at 50.455mm vs the 49.545mm design, calculating a kerf of 0.91mm. This was incorrect. The slots were too tight because I overestimated the kerf, making the fit impossible without damaging the material.

Attempt 2 Spacing

Final Attempt: The Modular Triangle

Remeasuring the kerf gave a more reasonable 0.365mm. I designed a 150mm equilateral triangle. Knowing the cardboard thickness was 4.4mm, I subtracted half the thickness (2.2mm) minus the kerf from the slot width to ensure a snug press-fit.

Two Triangles Laptop Stand

Laser Configuration Parameters

Kerf

0.365mm

Power (Min/Max)

65% / 75%

Speed

20mm/s

Material Thickness

4.4mm