File-specific calibration guide

Which calibration STL should you download first?

3DBenchy, a regular icosahedron, and a simple gear answer different questions. Choose the file that matches the symptom you want to investigate, then check the actual STL in your slicer.

Short answer: use 3DBenchy for a broad visual and dimensional benchmark; use the 40 mm icosahedron for a simple multi-face geometry check; use the gear only as a visual or fit-study candidate until you set your own tolerance and slicer plan. Image3D has not physically printed any of these files.

Rotatable browser preview of the original 3DBenchy STL. The STL download is unchanged.

Compare the three files before printing

FileUseful first questionCurrent Image3D evidenceLimit
3DBenchyHow do multiple small features and measured dimensions behave together?Original STL preserved; binary header, 225,706 triangles and file length checked.No Image3D slicer or physical print test.
40 mm icosahedronHow does a simple multi-face solid orient and slice?Public-domain source; 40 mm derivative; mesh screen and PrusaSlicer result with supports and a 5 mm brim.One slicer result does not establish physical print success.
Simple gear wheelIs this geometry worth a separate fit or tolerance experiment?CC0 source and hosted STL are recorded on the listing.Scale, tolerance, material, slicer behavior and functional fit are untested.

What each STL can and cannot diagnose

The official 3DBenchy measurement guide describes the boat as a calibration and challenge model. Image3D measured the original file at approximately 60 × 31 × 48 coordinate units. If your slicer interprets those units as millimetres, compare the slicer size with the intended reference before printing; read the STL scale guide for the file-level check.

The icosahedron gives you fewer interacting features. Its current listing documents a 40 mm derivative and a PrusaSlicer run, including the support and brim choices. Use that record to see what was actually checked; do not transfer the result to another printer, material, orientation or size.

A gear shape can help you plan a tolerance experiment, but the geometry alone says nothing about a working mechanism. If the part must mesh, carry load, or fit a shaft, define dimensions and clearance in CAD and test the actual printed assembly.

Download the exact file you inspected

3DBenchy

Original CC0 STL by Daniel Noree / Creative Tools. No Image3D print claim.

Download STL

Original source · CC0 license

40 mm icosahedron

Public-domain derivative. Slicer checked with supports and brim; no physical print.

Download STL

Source and rights

Simple gear wheel

CC0 STL. Mechanical function and slicer settings remain unverified.

Download STL

Source and rights

A repeatable check after download

  1. Open the actual STL, not only its derived preview, in the browser STL viewer and then the slicer you will use.
  2. Confirm units and final scale. A thumbnail cannot establish dimensions.
  3. Inspect orientation, layer preview, thin features, islands, supports and estimated material.
  4. Change one printer setting at a time and record the version of the STL, slicer profile, material and observed print result.

These files are free downloads with stated source rights. A usable STL and an attractive preview do not establish safe mechanical performance, printer compatibility or a successful physical print.

Frequently asked questions

Is 3DBenchy a calibration cube?

No. It combines several visible geometric features in one boat. Use a dedicated measured test piece when one dimension or one tolerance is the question.

Are these STL files open for commercial reuse?

The original 3DBenchy and gear listings cite CC0; the icosahedron listing cites a public-domain source. Check each linked source and consider trademark, patent, privacy and other rights that a copyright license does not resolve. See the CC0 license guide.

Does “slicer tested” mean “print tested”?

No. It means a specific file was processed by a slicer under recorded settings. The final printer, material and physical result remain separate evidence.