Tolerance Stack Analysis Using GD&T
- Introduction
- What are tolerance stacks?
- Fundamental rules and assumptions
- Review of geometric dimensioning and tolerancing
- Virtual Condition
- Definitions: local size vs. envelope; feature of size
- Material conditions: MMC, LMC, RFS
- Virtual condition for internal and external features
- Practice exercises
- Resultant condition
- Stacks with Coordinate Dimensions
- Basic steps in calculating a stack
- Review of the stack form
- Examples of single-part stacks
- Practice exercises
- Stacks with Runout and Concentricity
- Review of runout and concentricity
- Transferring tolerances to the stack form
- Examples and exercises
- Position Tolerances in Stacks
- Review of position RFS
- Applying position in the stack form
- The “bonus” tolerance concept
- Factoring bonus tolerance into the stack form
- Examples and exercises
- The “shift” tolerance concept
- Factoring shift tolerance into the stack form
- Examples and exercises
- Stacks with Profile
- Review of profile of a line and profile of a surface
- Bilateral and unilateral tolerancing
- Examples and exercises
- Stacks with Form Controls
- Review of flatness, straightness, circularity, cylindricity
- Rule #1: Size controls form
- “To” or “thru” rule
- “Adjacent” or “offset” rule
- Filling in the stack form
- Examples and exercises
- Stacks with Orientation Controls
- Review of parallelism, perpendicularity, angularity
- Filling in the stack form
- Examples and exercises
- Statistical Methods
- When to justify statistical methods
- Brief statistics review
- The “root sum square” (RSS) formula
- Modified RSS formulas (Bender and Gilson formulas)
- Monte Carlo simulation
- Wrap-up and Review of Drawings
- Review sample drawings
- Evaluations
