True Position Visual Analyzer

Calculate true position and instantly see if the feature is within tolerance

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True Position Visualizer Notes

What this tool does:

This tool calculates and visualizes true position deviation based on basic (nominal) dimensions and actual measured values. It helps machinists and inspectors quickly determine whether a feature is within tolerance.

Formula:

Radial Error = √[(ΔX)² + (ΔY)²]

True Position = 2 × Radial Error

Where:

ΔX = Actual X − Basic X

ΔY = Actual Y − Basic Y

Key Concept:

The tolerance zone is a circular area (diameter) centered on the nominal position.

If the actual point is inside the circle → PASS

If the actual point is outside the circle → FAIL

Example:

Basic position = (2.000, 1.500)

Actual position = (2.003, 1.497)

Tolerance = Ø0.010 in

ΔX = +0.003

ΔY = −0.003

Radial Error = 0.0042 in

True Position = 0.0085 in

Result: PASS

When to use this tool:

- Checking hole locations

- Inspecting machined features

- Verifying CMM measurements

- Training operators on GD&T

Important Note:

True position is not measured in X and Y separately. It is a combined geometric deviation based on both directions.

Machining Tip:

Small X and Y errors can combine into a larger true position error. Always check radial deviation, not individual axis values.

Shop Floor Tip:

If close to tolerance limit:

- Check fixturing

- Reduce tool deflection

- Verify datum setup

What you are seeing:

- Blue cross = Nominal position

- Red dot = Actual position

- Dashed circle = Tolerance zone

- Black line = Radial error

Tip:

Drag labels in the visualization if they overlap.

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