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Read the ArticleTPU 85A 3D Printing Material
Fused Deposition Modeling (FDM) · Flexible
Soft, highly elastic rubber-like material for the most flexible parts.
What Is TPU 85A?
TPU 85A is the softest flexible filament in our lineup, with high elasticity and excellent rebound. It suits parts that need to bend, stretch, or cushion - soft grips, gaskets, and wearables - where a rubber-like feel is the priority.
Thermoplastic Polyurethane (Shore 85A), printed with Fused Deposition Modeling (FDM). Every order is reviewed by our engineering team - no minimum order quantity.
When to choose TPU 85A
Choose TPU 85A when the part needs to feel and perform like soft rubber. At Shore 85A, this is the most flexible material we print - it compresses easily under finger pressure, stretches to 4x its length, and rebounds fully. It is the right pick for soft-touch grips, cushioning pads, flexible gaskets, and wearable comfort layers.
If you need flexibility with more structural integrity - bushings, tires, protective bumpers - TPU 90A is firmer and more wear-resistant while still flexible. If the part needs to hold its shape under any load, TPU 95A is the firmest option and also the most print-reliable. For truly structural parts that flex, SLS PA11 offers high elongation (40–50%) in a rigid nylon - a different kind of flexibility.
TPU 85A is manually quoted because its extreme softness requires careful print planning. Lead time may be slightly longer than auto-quoted materials. If your geometry is simple and you want fast turnaround on a flexible part, consider TPU 95A, which runs through our instant quoter.
Material Properties
Representative values - process- and orientation-dependent. Full technical datasheet available on request.
Process
Fused Deposition Modeling (FDM)
Tensile strength
12.0 ± 0.8 MPa
Elongation at break
330–450%
Flexural modulus
Low (elastomer)
Density
1.18 g/cm³
Max build size
245 × 245 × 230 mm
Min wall thickness
1.2 mm
Resolution / layer
150 µm
Relative cost
$$ (1 = lowest, 4 = highest)
Design Guidelines
Plan features to print reliably and assemble cleanly in TPU 85A. Need DFM help?
Min wall
1.2 mm - thicker = firmer feel
Shore hardness
85A - soft / very flexible
Clearance
0.5–0.7 mm - flex parts need more
Max size
245 × 245 × 230 mm - design for flex
Dimensional tolerances
Dimensional tolerance is ±0.5 mm or ±1.0% due to the flexible nature of the material - it deforms under its own weight during printing, especially on tall or thin features. Accuracy improves on shorter, wider geometries. Post-machining is not practical on TPU; design critical fits into the geometry with appropriate clearance.
Printing notes
TPU 85A prints at 220–240 °C nozzle / 30–50 °C bed at reduced speeds (20–30 mm/s) to prevent filament buckling in the extruder. A direct-drive extruder is required - Bowden setups cannot reliably push this soft a filament. Retraction must be minimized (0.5–1.0 mm max) to prevent jams. No enclosure is strictly required but stable ambient temperature helps adhesion. TPU is hygroscopic; we dry at 50 °C for 6+ hours before printing. Supports are difficult to remove from TPU without tearing the part, so we orient aggressively to avoid supports entirely.
How TPU 85A Compares
TPU 85A alongside related materials.
| TPU 85A | TPU 90A | TPU 95A | PA11 (SLS) | |
|---|---|---|---|---|
| Tensile strength | 12.0 ± 0.8 MPa | 12.5 ± 0.8 MPa | 27.3 ± 0.8 MPa | 47 MPa |
| Heat deflection (HDT) | - | - | - | 157 °C @ 0.45 MPa |
| Flexural modulus | Low (elastomer) | Low (elastomer) | Low–medium (elastomer) | ≈ 1,100 MPa |
| Elongation | 330–450% | 300–400% | 250–350% | 40–50% |
| Density | 1.18 g/cm³ | 1.20 g/cm³ | 1.22 g/cm³ | 1.02 g/cm³ |
| Relative cost | $$ | $$ | $$ | $$$ |
When to Use TPU 85A
Where TPU 85A fits, where it doesn't, and what to use instead.
Soft grips and overmolds
Shore 85A compresses under light finger pressure and rebounds instantly, delivering the tactile cushioning needed for ergonomic tool handles and controller grips.
Consumer ProductsGaskets and compression seals
330–450% elongation lets thin gasket profiles conform to irregular flanges under 15–25% compression without tearing or taking a permanent set.
EngineeringWearable comfort layers and pads
Soft enough to conform to body contours while absorbing vibration - used in orthotic liners, VR headset face gaskets, and helmet padding prototypes.
Medical DevicesVibration isolators and damping mounts
Elastomeric rebound absorbs 60–70% of transmitted vibration energy at frequencies typical of motor and compressor mounts (30–200 Hz).
RoboticsFlexible protective covers
Wraps around and stretches over irregular geometries for dust seals, connector boots, and cable strain reliefs that snap on and off without tools.
Consumer ProductsStrengths
- Softest material in the catalog at Shore 85A - compresses with light fingertip force for genuine rubber-like feel
- Highest elongation available (330–450%) with full elastic rebound for stretch-fit and conformable applications
- Abrasion resistance significantly exceeds rigid plastics - deforms around abrasive surfaces rather than wearing, extending service life
Keep in mind
- No structural load capacity - cannot hold shape under gravity on tall or cantilevered geometries; use TPU 95A or PA11 for load-bearing flex
- Prints at 20–30 mm/s with direct-drive extruder only - 3–5x slower than rigid materials; lead time runs slightly longer
- Supports are nearly impossible to remove without tearing the part - geometry must be oriented to eliminate overhangs entirely
Finishes & Colors
Finishing options and in-stock colors for TPU 85A.
Standard
As-printed; matte flexible surface.
Best for: Functional flexible parts
In-Stock Colors
Clear
Black
Red
Blue
Custom colors and dyeing available on request. Contact us for options.
TPU 85A FAQ
Lower Shore number = softer. 85A is the softest and most rubber-like; 90A is a balance of flex and durability; 95A is the firmest and most print-friendly. Tell us the feel you need and we'll advise.
TPU can produce flexible seals and gaskets. For watertight parts, design adequate wall thickness and compression - we'll review your geometry on quote.
85A compresses noticeably under light finger pressure; 90A requires moderate force to deform. 85A has higher elongation (330–450% vs 300–400%) and feels more rubber-like. 90A is more durable for wear applications like tires and bushings. Pick 85A for cushioning and soft touch, 90A for wear and durability.
Yes. TPU 85A's softness makes it effective for compression gaskets and seals. Design gaskets with 15–25% compression in mind and ensure uniform wall thickness. For large-diameter seals, 90A may hold shape better during installation.
Yes. All TPU grades have good abrasion resistance - significantly better than rigid plastics like ABS or PLA. 85A's softness means it deforms around abrasive surfaces rather than wearing, which extends life in sliding-contact applications.
Tolerances are wider than rigid materials - ±0.5 mm or ±1.0% typical. The material deforms under its own weight during printing, so tall thin features are less accurate. Design critical interfaces with generous clearance.
TPU has moderate UV resistance - better than PLA or ABS but not as good as ASA. For outdoor flexible parts, TPU 85A will last 1–2 years in direct sun before degradation becomes noticeable. Pigmented (non-clear) colors last longer.
TPU is generally well-tolerated for skin contact in wearables and grips. For specific skin-contact requirements, share your application details and we will confirm the appropriate grade.
Technical Documents
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