(408) 674–1451    gene@ttc-cogorno.com

Tolerance Analysis


Tolerance Analysis is a course that is presented through lecture, demonstration, discussion, and written exercises. It is an information packed course that will provide participants with the analytical tools needed to:

  • Set up a tolerance analysis problem
  • Determine the 100% tolerance stack–up in an assembly
  • Analyze fixed and floating fastener assemblies
  • Use statistical tolerancing

Preview the Tolerance Analysis Course Introduction (pdf)


Participants will be able to:

  • Identify factors pertinent to a stack–up analysis
  • Simplify complex assemblies
  • Draw a loop analysis diagram
  • Calculate MAX and MIN GAPS within an assembly
  • Calculate the statistical tolerance of an assembly


  • Mechanical Engineers
  • Design Engineers
  • Manufacturing Engineers
  • Anyone who may be required to determine assembly tolerances.


  1. The Basics
    1. Identify factors pertinent to stack–up analysis
    2. Designate positive and negative routes
    3. Position each part for a worst–case analysis
    4. Calculate mean dimensions and equal bilateral tolerances
    5. Calculate virtual and resultant condition boundaries
    6. Calculate the tolerance of fixed and floating fasteners
  2. Box Assembly
    1. Apply basic stack–up analysis to a box assembly
    2. Draw loop analysis diagram for the box assembly
    3. Designate positive and negative routes
    4. Calculate mean dimensions and equal bilateral tolerances
    5. Calculate MAX and MIN GAP
  3. Tolerance Stack–Up Analysis for Feature of Size
    1. Perform a loop analysis
    2. Determine the start and end points
    3. Graph values on a loop diagram
  4. Tolerance Stack–Up Analysis for Assemblies with Plus and Minus Tolerancing
    1. Calculate airspaces and interferences
    2. Alternative method of analysis
  5. Tolerance Stack–Up Analysis for a Floating Fastener Assembly
    1. Calculate resultant and virtual conditions
    2. Convert all dimensions to equal bilateral tolerances
    3. Mix widths and diameters in a numbers chart
    4. Graph the numbers into a tolerance stack–up diagram
    5. Determine all unknown gaps in a five–part assembly
  6. Tolerance Stack–Up Analysis for a Fixed Fastener Assembly
    1. Calculate overall housing requirements
    2. Calculate MIN and MAX GAPS within the assembly
  7. Tolerance Stack-Up Analysis for a Five–Part Assembly
    1. Perform a tolerance analysis of a five–part rotating assembly with a variety of geometric tolerances
    2. Practice simplifying a complex situation
    3. Learn to calculate part–to–part analysis from two parts to an infinite number of parts
    4. Determine assembly housing requirements
    5. Calculate radial clearance and interference
  8. The Theory of Statistical Probability
    1. Convert an arithmetical to a statistical tolerance
    2. Use the Root Sum Squares (RSS) formula
    3. Determine the tolerance statistically likely to be consumed
    4. Compare the statistical to arithmetical tolerance
    5. Calculate the percentage each tolerance may be increased
    6. Use a correction factor as a multiplier
    7. Reintegrate the statistical tolerance into the assembly