1. What Is Maximum Material Condition (MMC)?

Maximum Material Condition (MMC) is a GD&T concept that defines the condition where a feature contains the maximum amount of material within its stated limits. For a shaft, this is the largest size; for a hole, this is the smallest size.

2. How Does The Calculator Work?

The calculator uses the MMC calculation formula:

Where:

• \( Size \) — Nominal size of the feature (mm or inches)
• \( Geometric\ Tolerance \) — Geometric tolerance value (mm or inches)

Explanation: MMC determines the maximum material boundary in GD&T, which is crucial for ensuring proper fit and function in mechanical assemblies.

3. Importance Of MMC Calculation

Details: Accurate MMC calculation is essential for determining the worst-case scenario for assembly, ensuring parts will fit together properly even at their maximum material conditions.

4. Using The Calculator

Tips: Enter the nominal size and geometric tolerance in consistent units (either mm or inches). Both values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is the difference between MMC and LMC?
A: MMC (Maximum Material Condition) is when the feature contains the maximum amount of material, while LMC (Least Material Condition) is when it contains the minimum amount of material.

Q2: When should MMC be used in GD&T?
A: MMC should be used when you want to provide bonus tolerance as the feature deviates from its maximum material condition, allowing for more manufacturing flexibility.

Q3: How does MMC affect positional tolerance?
A: When MMC is applied to positional tolerance, it allows the tolerance zone to increase as the feature size deviates from MMC, providing bonus tolerance.

Q4: Can MMC be applied to all geometric tolerances?
A: No, MMC can only be applied to size features and certain geometric characteristics like position, concentricity, and symmetry.

Q5: What are the benefits of using MMC?
A: MMC allows for more manufacturing tolerance, reduces production costs, ensures functional requirements are met, and provides clearer inspection criteria.