1. What is True Position?

True Position is a GD&T (Geometric Dimensioning and Tolerancing) tolerance that controls the variation in the location of a feature from its exact theoretical position. It's calculated as twice the distance between the measured and theoretical positions.

2. How Does the Calculator Work?

The calculator uses the True Position formula:

Where:

• \( x \) — Measured X coordinate
• \( x_0 \) — Theoretical X coordinate
• \( y \) — Measured Y coordinate
• \( y_0 \) — Theoretical Y coordinate

Explanation: The formula calculates the radial deviation from the theoretical position and doubles it to get the true position value.

3. Importance of True Position Calculation

Details: True Position is critical in manufacturing for ensuring proper fit and function of assembled parts. It's widely used in automotive, aerospace, and precision engineering industries.

4. Using the Calculator

Tips: Enter all position values in inches. The calculator accepts decimal values for precise measurements. Ensure all fields are filled with valid numbers.

5. Frequently Asked Questions (FAQ)

Q1: What units does True Position use?
A: True Position is typically measured in inches or millimeters, matching the units of your drawing or specification.

Q2: How is True Position different from linear dimensions?
A: True Position considers the combined deviation in both X and Y directions, providing a more comprehensive tolerance zone.

Q3: What's the significance of the multiplier 2 in the formula?
A: The multiplier 2 converts the radial deviation to a diameter value, which is the conventional way to specify position tolerance.

Q4: Can True Position be calculated for 3D coordinates?
A: Yes, the formula can be extended to 3D by adding the Z-axis component: \( TP = 2 \times \sqrt{(x-x_0)^2 + (y-y_0)^2 + (z-z_0)^2} \)

Q5: How does True Position relate to MMC/LMC?
A: When used with Maximum Material Condition (MMC) or Least Material Condition (LMC), True Position tolerance can vary based on the actual size of the feature.