Fundamentals and Applications of Geometric Dimensioning & Tolerancing (GD&T)

Days: 3 

 7:30 AM- 4:30 PM MST


This intermediate course begins as an introduction to the ASME Y14.5 standard and the history of GD&T.  Attendees, through practical applications and exercises will demonstrate the strengths and advantages of GD&T as a design tool, manufacturing, and purchasing aid, and overall communications facilitating tool.  The course then shifts to cover some of the more used geometric dimensioning controls in mechanical engineering drawings.  Basic applications of positions are explained in greater detail.

Who Should Attend

  • Anyone who designs, drafts, engineers, purchases, manufactures, estimates, or inspects parts and assemblies.
  • Professionals who use the ASME Y14.5 Dimensioning and Tolerancing standard.
  • Quality Managers
  • Engineering Managers
  • Design Teams
  • Management Representatives
  • Project Teams
  • Prerequisites: A working understanding of technical drawings (perspectives, sections, details, etc) Possession of the ASME y14.5-2009 Dimensioning and Tolerancing standard is required.

Learning Objectives:

  • Review the “old” system versus GD&T including terminology and basic rules
  • General rules of dimensioning and drafting per the standard
  • Tolerance Zones- definition, concepts, comparisons to existing systems
  • GD&T symbology and definitions of controls
  • Datum Reference Frames- definition and proper construction and selections



  • Introduction: What is GD&T
  • Terminology & Basic Rules
  • Features and Rules of GD&T
    • Intro to Features and Material Conditions
    • Rule #1 of GD&T- Envelope Principle
    • Maximum Material Condition
    • Least Material Condition
    • The Feature Control Frame
  • Datums Control
    • Intro to Datums
    • Datum Reference Frame
    • Primary Datum Controls
    • Datum Targets
    • Intro to MMB and LBM
  • Adding GD&T to a Design
    • SLOF for Drawings-Size, Location, Orientation and Form
    • Choosing Datums
    • Virtual Conditions Calculations
  • Form Tolerances
    • Straightness-Surface
    • Straightness-Derived Median Line
    • Flatness-Surface
    • Flatness-Derived Median Plane
    • Circularity
    • Cylindricity
  • Orientation Tolerances
    • Parallelism-Surface
    • Parallelism-Axis
    • Perpendicularity-Surface
    • Perpendicularity-Axis
    • Angularity-Surface and Axis
  • Profile Tolerances
    • Profile of a Surface-Basics
    • Profile In-Depth-Modifiers
    • Profile of a Line
  • Location Tolerances
    • True Position
    • Functional Position Gauging
    • Concentricity
    • Symmetry
  • Runout Tolerances
    • Runout/Circular Runout
    • Total Runout