Inspection Brief · Geometric Dimensioning & Tolerancing
GD&T QUEST
Step into the inspection lab. On the granite plate stands a turned aluminium hub, waiting for its first-article check. Nothing on it is arbitrary — every face, bore and hole carries a tolerance.
PART GQ-HUB-001
MATERIAL 6082-T6
LAB 20.0 °C
UNITS mm
Stage 02 · Section A–A
Cut it open
Plane A–A runs straight through the hub's axis. Everything it cuts is hatched; the bore and the bolt holes stay clear. Look at the bottom: the flange face stands on the granite. That face is datum feature A, and the plate is its simulator — the plane the face rests on is datum A.
Stage 03 · Feature Inspection
Measure the features
Every frame points back to something you can see. Datum A is the plane of the granite plate the flange rests on. Datum B is the bore's axis, held square to A. Left of the axis the hub is cut away; right of it is the outside you would inspect.
FRAMES 6
TOL 0.01–0.2
DATUMS A B
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