Geometric Dimensioning and Tolerancing
Gregory S. Gay

Why This Seminar?

More and more enterprises are adding geometric dimensioning and tolerancing (GD&T) requirements to their conventionally toleranced engineering drawings, necessitating training of this type.  An understanding of GD&T is required in order to correctly interpret these GD&T controlled engineering drawings. 

The basics of GD&T will be reviewed.  Included will be some hands-on examples of measuring of part features using the application of GD&T principals.  Starting with basic print reading knowledge, the seminar will cover the symbols, terminology and rules of GD&T as based on ASME Y14.5M-1994.  Changes recently introduced in the 2009 version of the standard will be covered as well. 

Audience

This seminar is designed for inspectors, quality technicians, quality engineers, machinists, manufacturing engineers, their supervisors and managers, and others interested in a greater understanding of engineering drawings with GD&T specifications.  The seminar is presented from the perspective of an inspector.  Attendees should have an understanding of conventional engineering drawings, but prior knowledge of GD&T is not required.

Learning Outcomes

Upon completion of the seminar, participants will be able to:

• Identify datums and their use;

• Understand the relationship of size dimensions to the form of the part;

•  Interpret feature control frames;

• Compute Maximum Material Condition (MMC) & Least Material Condition (LMC) values;

• Compute positional tolerance zones including use of bonus tolerancing;

• Design simple MMC gages under GD&T control;

• Interpret the five general rules of GD&T;

• Inspect to composite positional tolerancing requirements;

• Apply graphical inspection analysis to GD&T control.

Outline

     1.       Dimensioning and Tolerancing - Millimeters - Inch - Angle

     2.       Fundamental Dimensioning Rule

     3.       MMC

     4.       LMC

     5.       Extreme Form Variation

     6.       Basic Fits

     7.       Alternate Dimensioning Practices

     8.       Geometric Characteristic Symbols and Terms

     9.       Feature Control Frames and Basic Dimensions

    10.    Datums and Datum Reference Frame Concept

    11.    Material Condition Symbols – MMC, LMC and RFS

    12.    Perfect Form Boundary

    13.    Tolerance of Form and Profile

    14.    Tolerance of Orientation and Run-out

    15.    Locational Tolerances & Bonus Tolerancing

    16.    Comparison Between Conventional and Positional Tolerancing

    17.    Zero Positional Tolerance at MMC

    18.    Virtual Condition Concept

    19.    Use of GD&T with Gages and Graphical Inspection Analysis

    20.    Concept of a MMC Hole to Another MMC Hole

    21.    Concept of a MMC Hole to a RFS Hole

Handouts

• A GD&T text book

• Fundamental Dimensioning Rules

• Certificate of Completion, with 1.5 Continuing Education Units