Geometric Dimensioning and Tolerancing

GD&T is an information packed seminar that will provide you with knowledge of tolerancing tools and techniques.

Geometric dimensioning and tolerancing (GD&T) is used to express engineering configuration from the designer to the manufacturer using a mechanical drawing. When properly specified, the system provides a uniform understanding and interpretation among all persons exposed to the drawing. In 1966 the Department of Defense, industry and educational institutions adopted a common American standard dealing with geometric dimensioning and tolerancing, ANSI/ASME Y14.5M. The problem experienced with this standard is a failure to educate adequately the drawing originators, manufacturers, and quality control personnel in its correct use.

You must be familiar with blueprint reading basics and the use of gauges for measurement.

You will learn

  1. How to insure interchangeability of mating parts.
  2. How to make additional quality and productivity improvements.
  3. How to bid contracts with increased confidence.
  4. How to interpret and apply ANSI Y14.5M-1982 and ASME Y14.5M-1994 standards.

Who will benefit

  • Inspectors
  • Supervisors
  • Quality assurance personnel
  • Engineers
  • Drafting personnel
  • Tool & die makers & machinists


  1. Introduction to GD&T and Engineering Drawing and Tolerances
    • The international language of prints and drawings & GD&T Comparison between GD&T and coordinate tolerancing Material conditions Chain vs. Datum dimensioning
  2. Introduction to Symbols and Terms
    • Rules and concepts of GD&T
  3. Data
    • Feature symbols
    • Types of datums Datum targets
    • Identification of datums on own company drawings
    • Inspection issues
  4. Material Condition Symbols
    • MMC, LMC, RFS
    • Conventional tolerances
    • Limits of size
    • Perfect form boundary
    • Primary, secondary and tertiary datum features and datum precedence
    • Bonus tolerance
  5. Tolerances of Form and Profile
    • Flatness, straightness, circularity, cylindricity profile
    • Free state variation
    • Form controls and basic dimensions
  6. Tolerances of Orientation and Run Out
    • Perpendicularity, angularity, parallelism
    • Circular and total run out
    • Combinations of geometric tolerances
    • Profile of a line and of a surface
    • Tangent plane
  7. Tolerances of Position and Location
    • Position tolerance and true position
    • Fasteners
    • Virtual condition – fit and function considerations
    • Concentricity and coaxiality
    • Symmetry
    • Positional tolerancing vs. conventional tolerancing

In-House Training Available

For additional information about in-house training, please email