A free download is not automatically permission to modify, sell or commission production. Preserve the exact source, creator and licence first. Then check whether the file, scale and geometry suit your intended use.
Download the English project worksheet. Open it as UTF-8 CSV, replace the guide context with your project inputs and record observations separately from acceptance decisions. Blank cells do not indicate a passed check.
Save the model's provenance
Record the direct model page, download date, filename, revision and creator as shown on the source page. A search result or image is insufficient. Keep the exact licence name and version, including requirements about attribution, sharing adaptations, commercial use and modifications. Do not substitute a vague “free” label for the licence.
Keep the exact licence and attribution
CC BY, CC BY-SA, CC BY-NC and CC BY-ND have different conditions. Consult the linked official licence and obtain clarification from the rights holder where your proposed production or modification is not clearly covered. Keep title, creator, source URL, licence URL and a description of changes with the project files.
If you prefer to select an existing design for a physical print, use the 3D print catalogue. It is a separate quote-based route, and rights remain model-specific. For your own download, proceed to the STL inspection checks after clarifying permission.
Check the actual file rather than its preview
Open it locally, note the format, count objects and inspect open edges. 3MF can contain units and other properties; STL does not declare a standard unit. An extension does not prove every possible field is present.
Resolve units and final dimensions
Compare the bounding box with an expected measurement and record units. Ten coordinate units might mean 10 mm or 10 cm; the source must resolve that. Scaling also changes openings, wall thickness and attachment features, so a larger overall size does not alone prove a useful product.
Fictional selection example
This example describes a pen tray with an explicit CC BY licence. No real model was downloaded or printed for the example.
| Check | Planning entry | Decision |
|---|---|---|
| Source | Full fictional model-page URL retained | Continue checking |
| Creator | Example Creator | Include in attribution |
| Licence | CC BY 4.0 | No NC restriction in this named licence |
| Modification | Width changed from 80 to 90 mm | Describe the modification |
| Format | STL | Confirm units separately |
| Expected size | 90 × 60 × 35 mm | Measure after import |
| Mesh condition | Unknown | No production approval |
A second file labelled only “free download”, without a creator or licence link, is a no-go even if it opens successfully. Technical usability and permission are separate checks.
Stop when evidence is missing
Do not proceed with an unclear creator or licence, incompatible commercial restrictions, prohibited necessary changes, unexplained scale or damaged mesh. Critical applications also require a separate suitability assessment. If the source later disappears, retain the original evidence rather than replacing it with a remembered licence label. This record-keeping is not a legal determination in a rights dispute.
Turn a selected model into an assessable print request
Once permission, scale and file condition are clear, send the exact model page, creator, licence and intended version with your 3D print request. Describe changes such as increased width so both permission and geometry can be assessed. A working download button is insufficient.
For damage, use the before-and-after STL repair check to identify what is missing and verify any repair. For unclear provenance, obtain permission or choose another design first. If you would rather choose from existing designs, start in the catalogue and make the enquiry from the selected model so its identity stays attached.