Apply a systematic 6-criterion evaluation rubric to your printed design — producing an evidence-based improvement brief for Version 2.
Learn — read and understand
Evaluation at Grade 4: higher standards than Grade 3
'The walls are strong' is a Grade 3 observation. 'The walls measured 3.1mm after printing — 0.1mm above the 3mm specification — and withstood 800g of vertical load without deflection' is a Grade 4 evaluation. Every criterion score must be supported by a specific measurement or quantified test result — not a description.
The Grade 4 evaluation rubric
Score each of the 6 criteria 1–4: (1) Functionality: does it hold 6 pencils? (2) Dimensional accuracy: do printed dimensions match CAD? Measure 3 key dimensions with calipers. (3) Print quality: surface finish, layer consistency, no defects. (4) Safety: no sharp edges. (5) Usability: ease of use. (6) Design intent: does it reflect the original concept?
Using calipers to generate evaluation evidence
Measurement protocol: measure each critical dimension 3 times and record the average. Example: hole diameter — measure 1: 7.3mm, measure 2: 7.4mm, measure 3: 7.3mm → average: 7.33mm. Compare to specification: 7.5mm modeled. Deviation: −0.17mm. Evaluation: 'Dimensional accuracy scores 4/4 — within 0.3mm of specification.'
From evaluation to Version 2 design brief
For every criterion scoring below 3, write a formal design change (ECR format): 'Criterion: Functionality. Score: 2/4. Evidence: Only 4 of 6 pencil holes accept a full-size pencil. Root cause: two holes measured 6.9mm (tolerance issue). Design change for V2: increase all hole diameters to 8.0mm to accommodate ±0.3mm shrinkage.'
Explore — Grade 4 evaluation criteria — what to measure for each
Tap to reveal
1. Functionality
Does it do its job? Test against specification. Measure: does it hold 6 pencils? Do all holes accept the pencil? Quantify pass/fail per item.
Tap to reveal
2. Dimensional accuracy
Measure 3 key dimensions with calipers. Record modeled vs printed. Acceptable: within ±0.3mm. Flag: deviation >0.3mm.
Safety: no sharp edges (test with finger — lightly). Usability: test with actual user. Design intent: compare to original sketch.
Activity — match each evaluation observation to the correct criterion
Drag or tap a label, then drop/tap on a zone
Functionality
Dimensional accuracy
Print quality
Safety
All 6 pencils fit and stand upright
Measured 79.8mm; modeled 80mm
Surface has visible layer lines
Top edge is sharp — cuts finger
Quiz — Designer Stage, Level 4
1What makes a Grade 4 evaluation DIFFERENT from a Grade 3 evaluation?
2Three caliper measurements of your hole give: 7.2mm, 7.4mm, 7.3mm. What should you record as the evaluation value?
3Your pencil holder scores 2/4 on dimensional accuracy because two holes measured 6.9mm against a 7.5mm specification. The V2 design change should state:
4A rough surface finish on your print does NOT necessarily mean the print failed the Functionality criterion because…
5What is an Engineering Change Request (ECR) format in the context of Grade 4 design evaluation?