GD&T Trainer Professional Edition
Based on ASME Y14.5M-1994 

Lesson 1: Dimensions and Drawings
Goal: Understand what dimensioning and tolerancing is.

• Describe what a dimension is.
  
• Describe what a tolerance is.
  
• Describe what a limit tolerance is.
  
• Describe what a plus-minus tolerance is.
  
• Identify the nominal of a dimension.
  
• Explain how dimensional limits are interpreted.
  
• Explain what the geometric dimensioning and tolerancing system is.
  
• Explain "ASME Y14.5M-1994."
• Identify the three major benefits of geometric dimensioning and tolerancing.

Lesson 2: Key Terms
Goal: Understand seven key terms used in geometric tolerancing.

• Define a feature.
  
• Define a feature of size.
  
• Define actual local size.
  
• Define actual mating envelope.
  
• Describe the maximum material condition of a feature of size.
  
• Describe the least material condition of a feature of size.
  
• Describe the term "regardless of feature size."

Lesson 3: Modifiers and Symbols
Goal: Understand the modifiers and symbols used in geometric tolerancing.

• Name the fourteen geometric characteristic symbols.
  
• Identify the five types of geometric characteristic symbols.
  
• Identify the six common modifying symbols used in geometric tolerancing.
  
• Identify the parts of a feature control frame.
  
• Identify the ten additional symbols used in geometric tolerancing.

Lesson 4: GD&T Rules
Goal: Understand Rule #1 and Rule #2.

• Explain Rule #1.
  
• Recognize the three components of the envelope principle.
  
• Determine when Rule #1 applies to a dimension.
  
• Describe the Rule #1 envelope boundary.
  
• Describe a limitation of Rule #1.
  
• List two ways Rule #1 can be overridden.
  
• Explain Rule #2 and Rule #2a.

Lesson 5: GD&T Concepts
Goal: Understand the concepts of basic dimensions, worst-case boundary, virtual condition, inner and outer boundary, and bonus tolerance.

• Describe a basic dimension.
  
• List two uses for basic dimensions.
  
• Explain the term "worst-case boundary."
  
• Explain the concept of virtual condition.
  
• Calculate the virtual condition of a feature of size.
  
• Explain the concepts of inner boundary and outer boundary.
  
• Explain the concept of bonus tolerance.
  
• Calculate the amount of bonus tolerance permissible.

Lesson 6: Flatness
Goal: Interpret the flatness control.

• Describe what flatness is.
  
• Describe the tolerance zone for a flatness control.
  
• Describe which modifiers can be used in a flatness control.
  
• Identify the three requirements in a flatness application.
  
• Describe how Rule #1 provides an indirect flatness control.
  
• Describe two common applications for a flatness control.
  
• Describe how a flatness control can be inspected.

Lesson 7: Straightness
Goal: Interpret the straightness control.

• Describe the difference between derived median line and axis.
  
• Describe the difference between derived median plane and centerplane.
  
• Describe what straightness is.
  
• Describe the tolerance zone for straightness applied to a surface.
  
• Describe which modifiers can be used with a straightness control applied to a surface.
  
• Determine if a straightness control is applied to a surface or feature of size.
  
• Describe the tolerance zone for a straightness control applied to a feature of size.
  
• Describe how Rule #1 provides an indirect straightness control.
  
• Recognize when a straightness control overrides Rule #1.
  
• Describe which modifiers can be used with a straightness control applied to a feature of size.
  
• Calculate the amount of bonus in a straightness MMC application.
  
• Describe two common applications of a straightness control.
  
• Describe how a straightness control can be inspected.

Lesson 8: Circularity
Goal: Interpret the circularity control.

• Describe what circularity is.
  
• Describe the tolerance zone for a circularity control.
  
• Describe which modifiers can be used in a circularity control.
  
• Describe how Rule #1 provides an indirect circularity control.
  
• List three conditions of a circularity application.
  
• Describe two common applications of a circularity control.
  
• Describe how a circularity control can be inspected.

Lesson 9: Cylindricity
Goal: Interpret the cylindricity control.

• Describe what cylindricity is.
  
• Describe three requirements of a cylindricity control.
  
• Describe the tolerance zone for a cylindricity control.
  
• Describe which modifiers can be used in a cylindricity control.
  
• Describe how Rule #1 provides an indirect cylindricity control.
  
• List three conditions of a cylindricity application.
  
• Describe a common application of a cylindricity control.
  
• Describe how a cylindricity control can be inspected.
  

Lesson 10: Planar Datums
Goal: Understand the datum system (planar datums).

• Describe the datum system.
  
• List three benefits of the datum system.
  
• Define an implied datum.
  
• Define a datum.
  
• Define a datum feature.
  
• Define a true geometric counterpart.
  
• Define a datum feature simulator.
  
• Define the datum feature symbol.
  
• Describe four ways to specify a planar datum.
  
• Describe how to reference datums in a feature control frame.
  
• Describe a datum reference frame.
  
• List six degrees of part freedom in space.
  
• Describe coplanar datum features.
  

Lesson 11: Datum Targets
Goal: Interpret datum targets.

• Describe datum targets.
  
• List three situations where datums targets should be used.
  
• Recognize the datum target symbol.
  
• State when a datum target specification is on the front or back surface in a view on a drawing.
  
• Describe why basic dimensions are used to locate datum targets.
  
• Draw a simulated gage for a datum target point specification.
  
• Draw a simulated gage for a datum target line specification.
  
• Draw a simulated gage for a datum target area specification.

Lesson 12: Size Datums (RFS)
Goal: Interpret feature of size datum specifications at RFS.

• Describe the datum that results from a feature of size datum feature.
  
• List three ways to specify an axis as a datum
  
• List three ways to specify a centerplane as a datum.
  
• Explain how feature of size datum references communicate size condition.
  
• Draw the datum feature simulator for an external feature of size datum axis (RFS primary).
  
• Draw the datum feature simulator for an internal feature of size datum axis (RFS primary).
  
• Draw the datum feature simulator for an internal feature of size datum centerplane (RFS primary).
  
• Draw the datum feature simulator for an external feature of size datum centerplane (RF primary).
  
• Describe coaxial datum features.

Lesson 13: Size Datums (MMC)
Goal: Interpret feature of size datum specifications at MMC.

• List three conditions when referencing a feature of size datum feature at MMC.
  
• Draw the datum feature simulator for an external feature of size datum axis (MMC primary).
  
• Draw the datum feature simulator for an internal feature of size datum axis (MMC primary).
  
• Explain the concept of datum shift.
  
• Recognize when datum shift is permissible.
  
• Calculate the amount of datum shift permissible.

Lesson 14: Orientation Controls
Goal: Understand the basics of orientation controls.

• Describe when to use each orientation control.
  
• Describe what controls the tolerance on implied 90° angles.
  
• Describe how parallelism is controlled when no symbol is shown.
  
• Explain the definition of perpendicularity.
  
• Explain the definition of angularity.
  
• Explain the definition of parallelism.
  
• Describe the common tolerance zones for orientation controls.
  
• List two requirements for orientation controls.
  
• List two indirect orientation controls.

Lesson 15: Perpendicularity
Goal: Interpret the perpendicularity control.

• List two common tolerance zones for a perpendicularity control.
  
• List two requirements of a perpendicularity control.
  
• Describe the tolerance zone for a perpendicularity control applied to a surface.
  
• Explain how a perpendicularity control applied to a surface affects its flatness.
  
• Explain the effect of applying a perpendicularity control to a feature of size.
  
• Explain how to specify a cylindrical tolerance zone for a perpendicularity control.
  
• Explain the tolerance zone when a perpendicularity control is applied to a cylindrical feature of size.
  
• Explain the effects of a MMC modifier in a perpendicularity control.
  
• Describe the gage for an application using a perpendicularity control applied at MMC.
  
• Describe two common applications for a perpendicularity control.

Lesson 16: Angularity
Goal: Interpret the angularity control.

• List two common tolerance zones for an angularity control.
  
• List two requirements of an angularity control.
  
• Describe the tolerance zone for an angularity control applied to a surface.
  
• Explain how an angularity control applied to a surface affects its flatness.
  
• Explain the effect of applying an angularity control to a feature of size.
  
• Explain how to specify a cylindrical tolerance zone for an angularity control.
  
• Explain the tolerance zone when an angularity control is applied to a cylindrical feature of size.
  
• Describe two applications for angularity.
  
• Explain how an angularity control can be inspected.

Lesson 17: Parallelism
Goal: Interpret the parallelism control.

• List two common tolerance zones for a parallelism control.
  
• List two requirements of a parallelism control.
  
• Describe the tolerance zone for a parallelism control applied to a surface.
  
• Explain how a parallelism control applied to a surface affects its flatness.
  
• Explain the effect of applying a parallelism control to a feature of size.
  
• Describe how to specify a cylindrical tolerance zone for a parallelism control.
  
• Interpret the effects of specifying the tangent plane modifier with a parallelism control.
  
• Describe two applications for parallelism.
  
• Explain how a parallelism control can be inspected.

Lesson 18: Position - Introduction
Goal: Understand the fundamental concepts of tolerance of position: the definitions and conventions, the advantages, and the basic theories.

• Define the term "tolerance of position."
• Define a tolerance of position control.
  
• Describe one requirement of a tolerance of position control.
  
• List two types of implied basic relationships common with tolerance of position.
  
• List six advantages of tolerance of position.
  
• List four types of relationships that can be controlled with tolerance of position.
  
• Describe when the MMC modifier should be specified in a tolerance of position control.
  
• Explain the virtual condition boundary theory for tolerance of position.
  
• Explain the axis theory for tolerance of position.

Lesson 19: Position - RFS/MMC/LMC
Goal: Interpret RFS, MMC and LMC tolerance of position applications.

• List three conditions that apply when a tolerance of position control is applied at RFS.
  
• Describe two common tolerance zone shapes for a tolerance of position control at RFS.
  
• Calculate the worst-case boundary for a feature of size controlled with tolerance of position at RFS.
  
• List three conditions that exist when an MMC modifier is used in a tolerance of position application.
  
• Describe the tolerance zone in tolerance of position MMC applications.
  
• Calculate the virtual condition of a feature of size controlled with a tolerance of position at MMC.
  
• Calculate the amount of bonus tolerance permissible for a tolerance of position application.
  
• Calculate the amount of datum shift available in a coaxial diameter tolerance of position application.
  
• Describe when a tolerance of position control should use the LMC modifier.
  
• Describe how bonus tolerance is calculated in an LMC position application.
  
• Describe four common applications for a tolerance of position control.
  
• Describe how a tolerance of position control applied at RFS can be inspected.
  
• Define the term "cartoon gage."
• Describe how a tolerance of position control applied at MMC can be inspected.

Lesson 20: Position - Special Applications
Goal: Interpret tolerance of position special applications.

• Describe the tolerance zone(s) in a tolerance of position application of an elongated hole.
  
• Describe when to use the projected tolerance zone modifier.
  
• Describe the tolerance zone(s) in a tolerance of position application with the projected tolerance zone modifier.
  
• Recognize when a tolerance of position control is used to control a symmetrical relationship.
  
• Describe the tolerance zone(s) in a tolerance of position application used to control the spacing and orientation of a hold pattern.
  
• Describe when a multiple single-segment tolerance of position control should be specified.
  
• Interpret a multiple single-segment tolerance of position control.
  
• Describe what a composite tolerance of position control is.
  
• Describe when a composite tolerance of position control should be specified.
  
• Interpret a composite tolerance of position control application.
  
• Recognize two major differences between multiple single-segment and composite position controls.

Lesson 21: Fastener Formulas
Goal: Calculate tolerance of position tolerance values using the fixed and floating fastener formulas.

• Describe a fixed fastener formula.
  
• Write the fixed fastener formula.
  
• Calculate tolerance of position tolerance values for fixed fastener applications.
  
• Describe a floating fastener formula.
  
• Write the floating fastener formula.
  
• Calculate tolerance of position tolerance values for floating fastener applications.
  
• List two limitations of using the fastener formulas.

Lesson 22: Concentricity
Goal: Interpret the concentricity control.

• Describe a median point.
  
• Describe the term "concentricity."
• Describe the tolerance zone for a concentricity control.
  
• List three requirements of a concentricity control.
  
• Interpret a concentricity control application.
  
• Describe one difference between concentricity and tolerance of position (RFS).
  
• Describe one common application for concentricity.
  
• Describe how a concentricity control can be inspected.

Lesson 23: Symmetry
Goal: Interpret the symmetry control.

• Describe the term "symmetry."
• Describe the tolerance zone for a symmetry control.
  
• Interpret a symmetry control application.
  
• Describe one difference between symmetry and tolerance of position (RFS).
  
• Describe one common application for symmetry.
  
• Describe how a symmetry control can be inspected.

Lesson 24: Circular Runout
Goal: Interpret the circular runout control.

• Describe what runout is.
  
• List two types of runout controls.
  
• List three ways a datum axis can be specified for a runout control.
  
• Explain what circular runout is.
  
• Describe the tolerance zone for a circular runout control (applied to a diameter).
  
• Describe how circular runout can be inspected.
  
• Describe how circular runout is a composite control.
  
• Determine the maximum amount of axis offset from a circular runout control.
  
• Interpret a circular runout application.
  
• Describe two common applications for circular runout.

Lesson 25: Total Runout
Goal: Interpret the total runout control.

• Describe what total runout is.
  
• List two requirements of a total runout control.
  
• Describe the tolerance zone for a total runout control (applied to a diameter).
  
• Describe how total runout is verified.
  
• Describe how total runout is a composite control.
  
• Determine the maximum amount of axis offset from a total runout control.
  
• Describe two similarities between circular and total runout.
  
• Describe two differences between circular and total runout.
  
• Describe two common applications for total runout.

Lesson 26: Introduction to Profile
Goal: Understand profile tolerancing.

• Describe how profile can be a related feature control or a form control.
  
• Describe the term "profile."
• Describe the term "true profile."
• Describe the term "profile control."
• Describe the four characteristics that profile can control.
  
• Describe the difference in tolerance zones for a profile of a surface and a profile of a line control.
  
• Recognize the four types of profile tolerance zone specifications.
  
• Describe a bilateral tolerance zone for a profile control.
  
• Describe a unilateral tolerance zone for a profile control.
  
• Recognize the symbol for "between."
• Recognize the symbol for "all around."
• Describe the extent to which a profile control tolerance zone applies on a part.
  
• List three advantages of using profile controls.

Lesson 27: Profile of a Surface
Goal: Interpret the profile of a surface control.

• List four part characteristics profile of a surface can be used to control.
  
• List two requirements of profile of a surface applied to a surface.
  
• Describe the part characteristics being controlled when a profile of a surface is used to control a surface location.
  
• List two requirements of a profile of a surface control applied to a polygon.
  
• Describe the part characteristics being controlled when profile of a surface is applied to a polygon.
  
• List two requirements of a profile of a surface control applied to a cone.
  
• Describe the part characteristics being controlled when profile of a surface is applied to a conical feature.
  
• List two requirements of profile of a surface applied to coplanar surfaces.
  
• Describe the part characteristics being controlled when profile of a surface is applied to coplanar surfaces.
  
• Describe two common applications for a profile of a surface control.
  
• Describe how a profile of a surface control can be inspected.

Lesson 28: Profile of a Line
Goal: Interpret the profile of a line control.

• List two requirements of a profile of a line control.
  
• Describe the tolerance zone for a profile of a line control.
  
• Describe how profile of a line is view dependent.
  
• Interpret a multiple single-segment profile application.
  
• Interpret an application with a profile of a line control used with coordinate tolerances.
  
• Describe two common applications for a profile of a line control.
  
• Describe how profile of a line can be inspected.