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Stop the Datum Confusion! - Video!

Consider the Translation Modifier - Video!

Determine the Origin of Measurement - Video!

Datum Targets - Video!

Datums Are Mutually Perpendicular - 1994, 2009, 2018

It Is Referencing the Datum — Not Itself - 1994

It Is Referencing the Datum — Not Itself - 2009

It Is Referencing the Datum — Not Itself - 2018

Datum Feature Control

Primary Datum Surface Control - 1994, 2009 & 2018

Tie your datum features together - 1994

Keep Identification of Datum Features Simple

Control Your Datum Features

General Profile Tolerance

Tie your datum features together - 2009 & 2018

Keep Datum Features Simple

Datum Feature Selection

Datums Based Upon Function

Slot as Primary Datum Feature

A Hole’s Primary Datum Feature - Video!

Two Holes

Two Holes as Datum Features - Horizontal - Video!

Two Holes as Datum Features - Diagonal - Video!

Datum Feature Types

Primary

Planar Datum Features - Video!

Center Planes as Datum Features - Video!

Spheres as Datum Features - Video!

Cones as Datum Features - Video!

Linear Extrusion - Video!

A Complex Feature as a Datum Feature May Constrain - Video!

Hole and Slot as Datum Features - Part I - Video!

Hole and Slot as Datum Features - Part II - 2009 - Video!

Secondary

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

Watch the Placement of Datum Identification Symbols... 2009

Datum Features

Repetitive Patterns

Datum Features Must Be Referenced - Video!

Axis vs. Center Line - Video!

A Datum Feature Is Not a Datum - Video!

Datum Reference Frame

Oblique Angle

Don’t Complicate Control of Your Datum Features

Does a Datum Reference Frame Need to be Fully Constrained - 1994, 2009, 2018

Displacement (Shift)

It Is Datum Shift - Not Bonus - Video!

Geometry Effect - Video!

Stop Using Datum Shift as a Bonus! - Video!

Why Datum Shift Is NOT a Bonus - Video!

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

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

MMC and LMC on a Datum Reference do not Affect the Feature’s Tolerance - 1994

MMC and LMC on a Datum Reference do not Affect the Feature’s Tolerance - 2009 & 2018

Exact Constraint

Rocking Datum Feature - Video!

Avoid Over Constraint in Your Designs

Orienting Datum Planes

Orienting Datum Planes - Video!

Tertiary Datums often Orient a Higher Order Datum Axis

Sufficient Size

Datum Features Must Be of Sufficient Size - Video!

Datums must be of sufficient size - 1994, 2009, 2018

Symbol Placement

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

Watch where you put that triangle - 1994, 2009, 2018

Apply Profile of a Surface to Surfaces - Video!

At MMC - Video!

Calculating Size Tolerance

Counting the Profile Tolerance Twice

Profile of a Line

Controlling Size Part l

Controlling Size Part ll

Unequal and Unilateral Profile

The most important control in GD&T is location, location, location - 1994, 2009, 2018

Protect your boundaries with Profile - 1994, 2009, 2018

Controlling Size and Form

Smooth the Surface with Profile on a Unit Basis - Video!

Between - Video!

Use Profile to Control Size and Form - 2009 - Video!

Applications

Irregular Feature

Use Profile to Open up Your Tolerances - 1994

Use Profile to Open up Your Tolerances - 2018

Use Profile to Open up Your Tolerances - 2009

As a General Tolerance

Simplify Your GD&T - 1994 & 2009

Irregular Features - 2009 - Video!

Simplify Your GD&T - 2018

Composite

Position can Control Location of Irregular Features - Video!

Composite Profile of a Surface is Your Most Powerful Tool

Composite Profile of a Surface is Your Most Powerful Tool

Coplanarity

For Coplanarity use Profile - 1994

Keep Surfaces Coplanar with Profile

For Coplanarity Use Profile - 2009 & 2018

Inspection

Measure Normal to the Surface

Parallel Surface - Use Profile of a Surface

Profile of a Surface - Easy to Measure

Use Profile of a Surface

Simplified Inspection

Reporting Profile - Video!

Remember, inspection is work versus risk - 1994, 2009, 2018

Inspecting Profile can be Simple - 1994

Inspecting Profile can be Simple - 2009

Inspecting Profile can be Simple - 2018

Report Profile So There Is No Confusion - 1994 & 2009

Report Profile So There Is No Confusion - 2018