How to Prepare Your STL File Before Ordering a Custom 3D Print

You can order a print of your own STL, 3MF or OBJ through Print My File. A few checks before uploading make it easier to get the size, colour choices and physical result you intend. This guide covers file preparation; if you have only a photo, drawing or idea, use a custom request instead.

Choose a file format for your result

• STL: a geometry file suited to a single-colour print. Check dimensions carefully because the file does not define a unit of measurement.
• 3MF: useful for models with units, multiple objects or compatible filament-colour assignments. Print My File accepts Bambu Studio and OrcaSlicer projects; not every saved printer setting can be carried into our production profile.
• OBJ: accepted for geometry. Companion texture files and an on-screen colour texture do not by themselves establish a printable multicolour order. Use a compatible painted 3MF for the uploader’s filament-colour workflow, or describe the intended result in a custom request.

The current upload limit is 60 MB. Keep the original design safely stored before exporting or simplifying a copy. Do not rename an unsupported extension to STL; export real geometry from the design application.

Confirm scale in millimetres

Write down the finished width, depth and height you want, including the base. Check those dimensions in your modelling software and again after upload. For example, a display figure intended to be 80 mm tall should not arrive as an 80-inch model. A file that imports successfully can still be the wrong size.

The current file service allows up to 250 × 250 × 250 mm per part. A larger object may need a considered split into separate printable parts. Decide how those parts align and join; splitting a helmet shell or display model does not automatically include assembly or finishing. Ask through the custom route when that work needs to be scoped.

Your pre-upload checklist

1. Check your printing rights. Keep the permission or licence for a third-party model. Buying or downloading a file does not necessarily authorize every use or a production batch.
2. Inspect the mesh. Look for holes, inverted faces, overlapping shells and disconnected pieces. View the sliced preview when you can; the solid model view can hide a missing wall.
3. Inspect the smallest features. Thin text, ears, fingers and projecting details may need a larger scale or a different design. A universal minimum wall thickness cannot guarantee every shape; orientation, material and the required use all matter.
4. Check part relationships. Identify separate pieces, which surfaces must fit, and whether moving joints are intentional. Scaling a model can also change its clearances.
5. Reduce excess file size carefully. Simplify an export copy if the mesh is unnecessarily dense. Compare it with the original so letters, curves and recognizable details survive.
6. Record the important face. Add a note if a portrait, logo or display front matters most. Support contact and visible layer lines affect the physical finish.

Prepare a multicolour 3MF

For the self-serve file service, use a compatible project with up to four filament colours per part. Check that the colour assignments are saved with the project, not just visible in a screenshot. Review the available filament choices and mapping in the order rather than expecting an exact screen-to-print colour match.

More colour changes can add purge material and print time. Compare the displayed price and its estimate or confirmed status after selecting your options. If you need more colours, fine gradients or a finish outside the uploader, send a custom request so the team can assess the project; a broader custom inquiry is not an automatic upgrade to full-colour printing.

When a file does not behave as expected

It will not upload: check the format, file size and whether the export opens in your design software. It is the wrong size: compare the bounding dimensions and units. Parts disappear in the slice: inspect thin walls, disconnected geometry and inverted faces. Colours are missing: check the project format and saved assignments.

Automatic mesh repair can help some files, but a repaired file is not proof that every detail, fit or surface is suitable. If you cannot resolve the issue, explain it in a custom request before commissioning design or repair work. Do not keep paying for a result whose required geometry has not been agreed.

From prepared file to order

Upload the file, choose the available material, colour, layer height, infill and quantity, then review the price. The uploader distinguishes the geometry estimate from a slice-confirmed quote. If the slicing result is unavailable, the estimate can be used to order. Review the displayed price status, selected options and checkout total before paying. Taxes and shipping are calculated at checkout.

PLA and PETG are currently offered in the uploader. The material guide helps you describe the display conditions and finish you need. Standard file-printing production is currently stated as 3–7 business days after payment, with shipping time additional. Priority handling concerns entry into production, not a guaranteed delivery date. See the shipping policy for destination information, including US orders.

No model file yet?

A figurine from your photos begins with a custom brief and authorized references. The concept, scope and quote are agreed before payment; model preparation follows concept approval and payment, and the final model is approved before printing. If an existing design suits you, shop our printed catalogue. Neither route requires you to become a 3D modeller.

For background on file structure and mesh problems, see the 3MF specification and Prusa’s mesh-repair guidance. Service options on Print My File determine what can be ordered here.