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Datum Terms - Video!

Translation Modifier - Video!

Must Be Referenced - Video!

Targets - Video!

Repetitive Patterns

Mutually Perpendicular

Referencing Itself?

Datum Feature Control

Primary Datum Surface Control - 1994, 2009 & 2018

Tie your datum features together - 1994

Keep It Simple


With General Tolerance

Tie your datum features together - 2009 & 2018

Datum Feature Selection

Function Example

Slot as Primary

Application - Video!

Two Holes

Horizontal - Video!

On a Diagonal - Video!

Datum Feature Types


Planar - Video!

Width - Video!

Sphere - Video!

Cone - Video!

Linear Extrusion - Video!

Complex - Video!

Hole and Slot - Video!

Hole and Slot Simulation - Video!


Watch the Placement of Datum Identification Symbols... 1994 & 2018

Watch the Placement of Datum Identification Symbols... 2009

Datum Features

Must Be Referenced - Video!

Axis vs. Center Line - Video!

Datum Not on Part - Video!

Datum Reference Frame

Oblique Angle


Does a Datum Reference Frame Need to be Fully Constrained?

Displacement (Shift)

Tolerances Do Not Change

Rotational Shift - Video!

Geometry Effect - Video!

Example - Video!

Application - Video!

Datum features can give you a shift-not a bonus - 1994

Datum features can give you a shift-not a bonus - 2009, 2018

Exact Constraint

Over Constraint

Rocking Datum Feature - Video!

Orienting Datum Planes

Tertiary Datum Feature

Using a Slot - Video!

Sufficient Size

Short Hole - Video!

Datums must be of sufficient size!

Symbol Placement

Watch placement of datum triangles in the latest Standard - 1994, 2009, 2018

Watch where you put that triangle!

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