Week 5 — 3D scanning and printing

This week’s topic: 3D scanning and printing.

Group assignment

This group assignment in Shenzhen Chaihuo focuses on FDM design-rule validation. Instead of relying on default slicer assumptions, we tested the machine envelope directly and converted observations into usable design limits for future coursework.

Work objective

We ran a controlled print-test campaign covering overhang, bridging, thin walls, and clearance gaps. With baseline settings fixed, the group could compare failure patterns and define evidence-backed rules for modeling and print preparation.

Lock a consistent baseline: machine, nozzle, filament, and slicer profile.
Use targeted test geometries that expose real failure boundaries.
Translate photo evidence into practical limits for classmates.

1) Baseline setup: machine, material, profile

We first documented the selected printer, nozzle setup, filament type, and one shared slicer profile. Keeping these fixed was necessary so differences came from geometry difficulty, not uncontrolled parameter changes.

Several different FDM 3D printers in the lab — Setup photo A - Available FDM printers; results tied to one chosen baseline machine.

Retrieving filament or stock for 3D printing from lab storage — Setup photo B - Filament selection matched to the recorded baseline profile.

2) Test geometry and procedure

The test suite included coupons for overhang angle, bridge span, wall thickness, and clearance gaps. Each geometry was chosen so print defects become visually obvious and easy to classify as pass, marginal, or fail.

3) Results and evidence review

We inspected coupons for sagging bridges, overhang collapse, wall instability, and fused clearances. The important outcome is not one perfect print, but a repeatable threshold map that predicts where designs are likely to fail.

3D-printed design-rules test coupons on a build plate — Result photo A - Test coupon set used to evaluate walls, gaps, and bridging behavior.

Inspecting 3D-printed design-rules test coupons on the build plate — Result photo B - Close inspection step before logging pass/fail regions.

3D-printed part testing maximum overhang angle — Result photo C - Overhang angle capability sample from the baseline machine.

4) Recommended rules for future designs

Use measured overhang and bridge limits when planning unsupported geometry.
Keep thin walls above the minimum threshold that remains stable across repeats.
Set moving-part gaps from the smallest clearance that consistently separates.
Always record the slicer profile with results so others can reproduce the outcome.