Lesson 4: Tolerance & Quality Assurance
Duration of Days: 2
Lesson Objective
SWBAT: Calculate the Upper and Lower limits of a part based on bilateral and unilateral tolerances.
Evaluate a series of measured parts to determine if they are "Accept," "Rework," or "Scrap."
What determines if a part is "good enough" to be sold?
How does a tighter tolerance increase the cost of a part?
Tolerance, bilateral, unilateral, nominal size, allowance, fit, clearance, interference, quality assurance, limit
CTE.MFG.D.23 (Quality control)
CTE.MFG.A.02 (Tolerance symbols).
Defining the "Range of Success." Interpreting blueprint tolerances to make high-stakes "Go/No-Go" decisions on finished parts.
DOK Level: 3 (Strategic Thinking)
Support: Use a visual "Number Line" to plot the Upper Limit and Lower Limit of a part.
Extension: Introduce basics of GD&T (Geometric Dimensioning and Tolerancing) like flatness or circularity.
"The QA Inspector Exam" – A simulation where students must inspect a bin of 10 parts and sign off on a quality report based on specs.