3D Print Tolerance & Clearance Test Generator (STL)

See 3D Print Tolerance & Clearance Test Generator (STL) in action

azrscorp.com/quickfix/3d-print-tolerance-clearance-test-generator-stl/

1Enter the nominal size and clearance range.

2Generate and download the plate.

3Print with your normal settings.

Free 3D Print Tolerance & Clearance Test Generator

Why does an 8 mm hole print as 7.8 mm? Printers over-extrude, plastic shrinks and round holes polygon-ise, so every printer and material needs its own hole offset. This generator creates a plate with a row of holes at your nominal size plus increasing clearance (for example 0, 0.05, 0.10 … 0.35 mm), with numbers raised beside each hole and a matching plate of pegs at the nominal size.

Print it with your usual settings, try the pegs or your real bolt, magnet or shaft in each hole, and note the first one that fits the way you want. The table gives each hole's exact size. Use that clearance in every future design.

Key features

How to use it

1. Enter the nominal size and clearance range.
2. Generate and download the plate.
3. Print with your normal settings.
4. Test fit and note the winning hole.

Worked example

Example

A nominal 8 mm test from 0 to 0.35 mm in 0.05 mm steps gives holes of 8.00 to 8.35 mm; on a typical 0.4 mm FDM printer hole 3 (8.10 mm) is a snug press fit and hole 5 (8.20 mm) slides freely.

Who uses this tool

Tips for the best results

• Print with the same material and settings as the real part.
• Print slowly for a more accurate hole.
• Remember horizontal and vertical holes differ.
• Repeat for each material.

Common mistakes to avoid

• Testing with the wrong settings.
• Measuring holes with calipers instead of test fitting.
• Using one clearance for different materials.

Frequently asked questions