FDM or resin: which technology to choose
FDM and resin are not two levels of the same technology. They use different materials, preparation and post-processing. The useful choice starts with the part and the workflow you can support.
Two different processes
FDM deposits molten thermoplastic filament layer by layer. The part may need supports removed and finishing, but is often usable once it has cooled.
MSLA selectively cures photosensitive resin in a vat. The fresh part must be handled with protection, washed, dried and post-cured according to the resin instructions.
Detail, size and geometry
Resin is generally favoured for very fine surface detail, miniatures, jewellery and small complex objects. FDM is often more practical for larger parts, prototypes and functional components.
Neither technology removes the need for support planning and orientation. Support shape, marks and the rules for cavities, bridges and slopes differ.
Materials and properties
FDM provides a broad range of thermoplastics, from simple materials to flexible and composite options, within the machine's limits. Resins are formulated for specific uses, but many standard resins are more brittle under impact than common filaments.
Do not infer food-contact, medical suitability or general safety from a product name. Regulated uses require products and processes certified for the intended application.
Workspace and recurring cost
For FDM, consider the printer, spools, spares and ventilation appropriate to the material. For resin, add a protected area, PPE, solvent or washing system, post-curing and waste handling.
Compare the cost of the complete process, not only the printer or the material price per kilogram or litre.
Quick orientation
- First printer, prototypes and larger parts: generally FDM.
- Miniatures and fine surface detail: generally resin.
- Broad selection of engineering thermoplastics: FDM.
- Less post-processing and liquid handling: FDM.
- Resin: only if you can organise PPE, washing, curing and disposal.
These are orientation points; the specific model, material and application can change the decision.
If both technologies can make your part, choose the process you can repeat safely, neatly and sustainably.