SLA resin choice matters more than people think. The wrong resin cracks under load; the right one lasts years.
Standard resin
Rigid, brittle, cheap. Great for visual models, figurines, and prototypes that will not see mechanical stress.
- Price: $
- Shore hardness: ~85D
- Best for: display pieces, architectural models, presentation prototypes
- Fails at: anything that drops, flexes, or carries load
Tough resin
Formulated to mimic ABS. Less brittle, better impact resistance.
- Price: $$
- Tensile strength: ~40 MPa
- Best for: functional prototypes, snap-fit enclosures, consumer product mock-ups
- Watch out: still not as tough as sintered nylon. For parts that cycle under load, an FDM nylon or PETG print is the better option on this platform.
Flexible / elastic resin
Rubbery feel, stretches up to 160%. Different suppliers have different hardness options (30A to 70A Shore).
- Price: $$$
- Best for: gaskets, soft grips, wearables, cushioning parts
- Watch out: not as tear-resistant as silicone molds.
Durable (Polypropylene-like) Resin
Low stiffness, high elongation. Mimics polypropylene.
- Price: $$$
- Best for: living hinges, snap caps, flexible clips
- Watch out: poor heat resistance.
High-temperature resin
Heat deflection 200+ °C.
- Price: $$$$
- Best for: injection mold masters, prototypes that see hot environments, parts going near heat sources
- Watch out: more brittle than standard resin.
Dental / medical resins
Biocompatible, certified for short- or long-term contact with skin or tissue.
- Price: $$$$$
- Best for: surgical guides, dental models, trays, orthotics
- Watch out: only makers with certified printers and workflows can print these. Ask specifically.
Quick selector
| Need | Pick |
|---|---|
| Looks good on a shelf | Standard |
| Functional prototype | Tough |
| Rubber-like part | Flexible |
| Snap-fit clip | Durable |
| Hot environment | High Temp |
| Medical or dental | Dental/Medical (certified) |
Universal tip
All SLA prints need UV post-curing and should be kept out of direct sunlight long-term. Even "UV stable" resins yellow eventually. If your part will live outdoors, coat it with a UV-resistant clear lacquer.