STL or 3MF? What to know about printing files
Found both STL and 3MF files for a model? Either may work for a simple, single-colour object. For several parts or colours, keep the original 3MF project too. The formats store different kinds of information.
STL primarily describes the shape
STL represents an object’s surface using triangles. It is widely used and often suitable for sharing a simple part. Standard STL does not preserve project colours or material settings, and has no standardised unit. Check the size after opening it.
3MF can hold more information
3MF can contain geometry, units, multiple objects and, where supported, colour and material information. Slicers may also store their own project data in it. This is particularly useful for assemblies containing several parts.
The 3MF extension alone does not guarantee that every application understands every piece of data. Handling a manufacturer-specific plate layout or painting also depends on the application. Keep the file and check it as well.
What should you check in the calculator?
- Size. The displayed width, depth and height should match your intention.
- All parts. For multiple-plate projects, look beyond the first preview.
- Quantity. One finished assembly may consist of several separate printed parts.
- Warnings. If a part needs checking, do not treat a missing estimate as zero cost.
For complex files, the web preview may simplify the displayed surface to keep it responsive. Display detail and the model data needed for production are different things. If you notice a difference from the original project, mention it when discussing the job.
What should you include with a colour model?
A screenshot alongside the original 3MF can prevent misunderstandings. The web view does not currently show all original per-surface AMS painting. The image helps clarify intended colours but does not replace the 3D file. Read more in our multicolour printing article .
Selecting a file does not place an order
On the custom printing calculator , you can view the model and request a preliminary estimate. Choosing a file is not submission: enter your contact details and submit the quote form too. A successful submission saves the original file and plate settings and provides email confirmation and tracking. This does not start production.
Include the source link, size, material and colour preferences, and quantity in your message. If the file will not open, include the exact error message; this is more useful than just a screenshot of the object.
About the formats: 3MF Consortium – frequently asked questions.
What happens to the submitted file?
The quote request links the original file with selected dimensions, materials, colours and every plate in the project. After the confirmation email, you can track the request. We will contact you if a part does not display properly or a multicolour assembly needs more information. A successful upload is not production approval.
If you change the model, use a clear filename such as holder-v2. Check the size and quantity for the new version as well; do not rely only on an earlier screenshot.
