PA12 vs resin vs TPU: which 3D printing material should you choose?
Updated 5 November 2026 · 3 min read
In short
PA12 (laser-sintered nylon) is the default for functional parts: strong, impact-resistant, fine outdoors and up to about 95 °C. Resin gives the best detail and a smooth surface, but it's brittle and softens around 50 °C. TPU and TPE are flexible: grips, pads, bump stops, end caps. On a multi-part object you combine them: PA12 for the structure, TPE wherever it touches.
- Everyday functional part: PA12. Highly detailed display part: resin. Part that bends or cushions: TPE or TPU.
- Outdoors: white or black PA12, TPE. No resin in the sun.
- None of these materials is certified for food contact.
- The table at the bottom of the page reads the rules live from the workshop's catalogue.
The comparison in one table
| PA12 (SLS / MJF) | Resin (SLA) | TPE / TPU (flexible) | |
|---|---|---|---|
| Stiffness | High, with slight give | High but brittle | Low: the part bends |
| Impact resistance | Good | Poor | Excellent |
| Smallest detail | 0.2 mm | 0.4 mm (0.1 mm in MJP) | 0.8–1 mm |
| Minimum wall | 0.7 mm in SLS, 0.5 mm in MJF | 0.6–1 mm | 0.8 mm (TPE), 1.6 mm (FDM TPU) |
| Surface | Matte, slightly grainy; vapour smoothing available | Smooth, close to moulded | Matte; visible lines in FDM |
| Heat | Up to ≈ 95 °C | Softens around 50 °C | ≈ −20 to 60 °C (TPE) |
| Outdoors, UV | Yes (white, black) | No: yellows and turns brittle | Yes |
| Moving parts printed in place | Yes, 0.5–0.6 mm clearance | No | TPE yes, FDM TPU no |
| Typical uses | Clips, enclosures, mechanisms, mounts, storage | Display prototypes, miniatures, light diffusers | Grips, pads, seals, bump stops, end caps |
PA12, the default material
PA12 is an engineering nylon printed by selective laser sintering (SLS) or Multi Jet Fusion (MJF): the machine fuses powder layer by layer, with no supports. Parts are strong, light (density ≈ 1) and slightly flexible, which is what makes clips and hinges possible.
- SLS: white, dyed black or dyed colours; the largest build sizes (about 650 × 550 × 350 mm in white).
- MJF: natural grey or matte black, slightly crisper detail, walls from 0.5 mm.
- Vapour smoothing: a sealed, satin surface, but a 1.5 mm minimum wall and no moving parts printed in place.
- Care: hand-wash in soapy water; avoid the dishwasher, since the raw surface is porous.
Resin, for detail and finish
Stereolithography (SLA) cures liquid resin with a laser. It gives smooth surfaces and fine detail, in standard white, black or clear. Ultra-fine resin (MJP) goes down to 0.1 mm detail, for miniatures.
- Best for display prototypes, light diffusers (clear resin) and small, highly detailed parts.
- Avoid it outdoors, near heat (it softens around 50 °C) and for parts that take knocks.
- No parts printed in place and no enclosed volumes: each moving part is printed separately.
TPU and TPE, when you need flex
Sintered TPE (Shore ≈ 88A, roughly a shoe sole) stays flexible from about −20 to 60 °C and grips well: handles, pads, end caps, bump stops. TPU 95A, printed by fused filament (FDM), is firmer and cheaper, but you can see the layer lines and detail is coarser (1 mm).
Flexible parts need thicker walls and wider clearances: 2 mm between moving parts in TPE, against 0.5 mm in PA12.
Choosing part by part
An object doesn't have to be one material. objekto's “Rebound” walking cane combines black PA12 for the structure, TPU for the shock-absorbing tip, and an off-the-shelf aluminium tube and stainless spring. A few simple rules:
- It carries load, clips or screws together: PA12.
- It has to be very fine, very smooth or translucent, and stays indoors: resin.
- It touches your hand, the floor or a surface you want to protect: TPE.
- It gets hot, cuts, springs or touches food: an off-the-shelf part (metal, glass), listed in the assembly guide.
On objekto, the AI suggests a material for each part; you can change it before you order and watch the price update. The guide Designing a multi-part object explains how the parts go together.
Live rules from the catalogue
| Material | Min. wall | Min. detail | Min. clearance | Max. size (mm) | Properties | Price |
|---|---|---|---|---|---|---|
| PA12 white (SLS) | 0.7 mm | 0.2 mm | 0.5 mm | 650 × 550 × 350 | rigid · outdoor | $ |
| PA12 dyed black (SLS) | 0.7 mm | 0.2 mm | 0.5 mm | 320 × 230 × 180 | rigid · outdoor | $ |
| PA12 dyed colours (SLS) | 0.7 mm | 0.2 mm | 0.5 mm | 320 × 230 × 180 | rigid | $ |
| PA12 vapour smoothed (SLS) | 1.5 mm | 0.5 mm | 0.7 mm | 440 × 375 × 345 | rigid · outdoor | $$ |
| PA12 natural grey (MJF) | 0.5 mm | 0.2 mm | 0.6 mm | 380 × 380 × 284 | rigid · outdoor | $ |
| PA12 matte black (MJF) | 0.5 mm | 0.2 mm | 0.6 mm | 360 × 210 × 210 | rigid · outdoor | $ |
| PA12 black vapour smoothed (MJF) | 1.5 mm | 0.5 mm | 0.7 mm | 360 × 210 × 210 | rigid · outdoor | $$ |
| PA12 full colour (MJF) | 1 mm | 0.2 mm | 0.6 mm | 330 × 247 × 190 | rigid | $$$ |
| Flexible TPE (SLS, Shore ≈ 88A) | 0.8 mm | 0.8 mm | 2 mm | 220 × 190 × 190 | flexible · outdoor | $$$ |
| Flexible TPU 95A (FDM)rules to be confirmed | 1.6 mm | 1 mm | 0.8 mm | 250 × 250 × 250 | flexible · outdoor | $ |
| Standard resin (SLA, Somos GP Plus) | 1 mm | 0.4 mm | 0.2 mm | 790 × 790 × 590 | rigid | $$ |
| Clear resin (SLA, Watershed XC)rules to be confirmed | 1 mm | 0.4 mm | 0.2 mm | 790 × 790 × 590 | rigid | $$ |
| Black resin (SLA, Watershed Black)rules to be confirmed | 1 mm | 0.4 mm | 0.2 mm | 790 × 790 × 590 | rigid | $$ |
| Ultra-fine resin (MJP Visijet)rules to be confirmed | 1 mm | 0.1 mm | 0.2 mm | 298 × 203 × 185 | rigid | $$$ |
| Cast brass (lost wax) | 0.6 mm | 0.4 mm | 0.3 mm | 100 × 89 × 89 | rigid · outdoor | $$$$ |
| PETG (FDM) | 0.5 mm | 0.5 mm | 0.5 mm | 300 × 300 × 300 | rigid · outdoor | $ |
| PLA (FDM) | 0.5 mm | 0.5 mm | 0.5 mm | 300 × 300 × 300 | rigid | $ |
Every material and its colours are shown on the Materials page.
Frequently asked questions
Which material is the strongest?
For everyday use, PA12: stiff, impact-resistant and slightly flexible, it takes knocks better than resin. Cast brass is harder, but only for small decorative pieces.
Which material for outdoor use?
White or black PA12, with TPE for the flexible parts. Avoid resin and dyed colours, which age in UV light.
Can printed parts go in the dishwasher?
It's not recommended: raw PA12 is porous and resin dislikes heat. Wash parts by hand.
Which material is food-safe?
None of the materials on offer is certified for food contact. For kitchen tools, objekto uses an off-the-shelf stainless-steel part wherever it touches food.