3d-printingHow-ToBeginner · 3 min read

How to Do Dimensional Accuracy Check on 3D Print

To perform a dimensional accuracy check on a 3D print, measure key features of the printed object using precise tools like calipers and compare them to the original design dimensions. This helps identify any size deviations caused by printing settings or material behavior.

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Syntax

Dimensional accuracy checking involves these steps:

Measure: Use tools like digital calipers to measure length, width, height, and critical features on the 3D print.
Compare: Match these measurements against the original CAD or design file dimensions.
Calculate deviation: Find the difference between printed and designed sizes to assess accuracy.

python

def check_dimensional_accuracy(measured, designed):
    """Calculate dimensional deviation in mm."""
    deviation = measured - designed
    return deviation

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Example

This example shows how to calculate dimensional deviation for a 3D printed cube edge.

python

designed_length = 20.0  # mm, design dimension
measured_length = 19.7  # mm, measured on print

def check_dimensional_accuracy(measured, designed):
    deviation = measured - designed
    return deviation

result = check_dimensional_accuracy(measured_length, designed_length)
print(f"Dimensional deviation: {result} mm")

Output

Dimensional deviation: -0.3000000000000007 mm

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Common Pitfalls

Common mistakes when checking dimensional accuracy include:

Using inaccurate or uncalibrated measuring tools, leading to wrong results.
Measuring at the wrong points or angles on the print, causing inconsistent data.
Ignoring environmental factors like temperature that can cause material expansion or shrinkage.
Not accounting for printer settings like layer height or extrusion width that affect final size.

Always calibrate your tools and measure multiple times for reliable results.

python

wrong_measurement = 21.0  # Incorrectly measured
correct_measurement = 20.1  # Correct measurement

def check_dimensional_accuracy(measured, designed):
    return measured - designed

print("Wrong deviation:", check_dimensional_accuracy(wrong_measurement, 20.0))
print("Correct deviation:", check_dimensional_accuracy(correct_measurement, 20.0))

Output

Wrong deviation: 1.0 Correct deviation: 0.10000000000000142

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Quick Reference

Tips for effective dimensional accuracy checks:

Use digital calipers for precise measurements.
Measure multiple points on the print to check consistency.
Compare measurements to original CAD dimensions carefully.
Consider printer calibration and material properties.
Document deviations to adjust printer settings for future prints.

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Key Takeaways

Use precise tools like digital calipers to measure your 3D print dimensions.

Compare measured values directly with your original design to find deviations.

Measure multiple points and repeat measurements for accuracy.

Account for printer settings and material behavior when analyzing results.

Calibrate your measuring tools and printer regularly to maintain accuracy.