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Updated July 22, 2026

TPU Filament Buying Guide: Flexible 3D Printing Explained

TPU (thermoplastic polyurethane) is the most popular flexible 3D printing filament. We explain shore hardness, best printers for TPU, drying requirements, and the top brands to buy.

Material Guide
TPU (thermoplastic polyurethane) is the go-to material for flexible 3D printing. It combines rubber-like elasticity with the convenience of FDM printing, making it ideal for gaskets, phone cases, vibration dampeners, and wearable parts. But TPU is more nuanced than PLA or PETG. Shore hardness, printing speed, and drying all matter much more than with rigid filaments. This guide covers everything you need to pick the right TPU for your project. Understanding Shore Hardness TPU is graded by Shore hardness, which measures how resistant the material is to indentation. The two scales you will encounter are Shore A (softer) and Shore D (harder): - 85A–92A Shore A: Soft, stretchy, rubber-like. Ideal for gaskets, seals, bumpers, and wearable parts. Behaves similar to a rubber band or pencil eraser. Brands: NinjaTek NinjaFlex, eSUN eTPU-85A. - 95A–98A Shore A: Semi-flexible, tough, springy. The sweet spot for functional parts — phone cases, vibration dampeners, protective covers, and custom tools. This is the most common TPU range. Brands: Polymaker PolyFlex TPU95, Overture High Speed TPU, Sunlu TPU. - 60D–72D Shore D: Stiff, impact-resistant, almost rigid. Behaves more like nylon or polypropylene. Used for snap-fit parts, hinges, and high-wear applications. Brands: MatterHackers PRO Series TPU. For your first TPU print, start with a 95A Shore A material — it is forgiving enough to dial in settings while still being useful for real parts. Printer Requirements TPU requires a direct-drive extruder. Bowden setups struggle because the flexible filament buckles in the long tube between the extruder and hotend. All of these printers print TPU well out of the box: - Prusa MK4 / Core One: Excellent TPU performance with direct drive. Print at 20–30 mm/s for soft TPU. The open frame makes access easy. - Bambu Lab X1 Carbon / P1S / A1 / A1 Mini: Good TPU capability, but filament must be fed through the external spool holder — the AMS cannot handle flexible materials. - Creality K1 / K1 Max: Direct drive with a short filament path. TPU is reliable at moderate speeds. Use a side-mounted spool holder to reduce friction. - Sovol SV06 / SV07: Direct drive at a budget price. TPU works well at slower speeds (15–25 mm/s). Important: If you have a Bowden printer like a stock Ender 3, you can still print harder TPU (95A+) at very slow speeds, but expect stringing and inconsistent extrusion. A direct-drive upgrade is recommended. Printing Settings TPU printing requires slower speeds and specific temperature windows: - Nozzle temperature: 220–250 °C (dependent on hardness — softer TPU needs hotter temps) - Bed temperature: 40–60 °C (60 °C for better adhesion with soft TPU) - Print speed: 15–30 mm/s for soft (85A–92A), 30–60 mm/s for harder (95A–98A) - Retraction: Minimal or none — TPU compresses and can cause jams if retracted aggressively. Start at 0.5–1 mm at 20–30 mm/s. - Cooling: Fan at 25–50% for bridges/overhangs, otherwise minimal. Too much cooling weakens layer adhesion. - Bed surface: PEI sheet with glue stick works well. Textured sheets also work. Avoid glass alone — TPU can fuse to glass. - Build plate adhesion: A brim is recommended, especially for tall or small-contact-area parts. Drying TPU TPU is highly hygroscopic. It absorbs moisture from the air faster than PLA or PETG. Wet TPU produces: - Bubbling, popping, and stringing - Rough surface finish - Weak, brittle parts - Inconsistent extrusion Dry TPU at 45–55 °C for 8–12 hours before printing. A dedicated filament dryer (Sunlu S2, Sovol SH01) works best. Store opened spools in vacuum bags with desiccant or in a dry box. Once dried, TPU should be printed within 6–12 hours or stored sealed. Top TPU Brands Polymaker PolyFlex TPU95 The gold standard for 95A TPU. Excellent diameter tolerance (±0.03 mm), consistent extrusion, and good layer adhesion. Prints reliably on most direct-drive printers. Available in 12+ colors. The PolyBox 3-pack offers good value. NinjaTek NinjaFlex The original flexible filament. 85A Shore hardness — extremely soft and stretchy. Requires very slow speeds (15–20 mm/s) and a direct-drive extruder. Excellent quality and customer support from a US-based company. Overture High Speed TPU 95A Shore with a formulation optimized for slightly faster printing (30–50 mm/s). Good diameter consistency (±0.03 mm). A solid all-around TPU for functional parts. The 4-pack bundle provides good value. eSUN eTPU A budget-friendly 95A TPU that prints well with a bit of tuning. Slightly more prone to stringing than Polymaker or Overture, but at a significantly lower price point. Good for learning TPU without spending $35+/spool. Sunlu TPU Another budget option, available in 95A and a softer variant. Good for prototyping and non-critical parts. Can be stringy; drying thoroughly before printing helps significantly. What to Print with TPU TPU excels at parts that need to flex, grip, dampen vibration, or withstand repeated impact: - Gaskets and seals (weatherstripping, enclosure seals) - Phone cases and tablet stands - Vibration dampening feet for printers and electronics - Custom RC car tires and drone bumpers - Wearable parts (watch bands, headphone pads) - Cable management clips and strain relief - Robot grippers and soft robotic actuators

FAQ

Can I print TPU on any 3D printer?
TPU prints best on direct-drive extruders. Bowden-style printers can print harder TPU (95A+) at slow speeds, but soft TPU (85A–92A) will likely jam or produce poor results. If you have a Bowden printer, consider a direct-drive upgrade or stick to harder TPU formulations.
Is TPU food-safe?
Most TPU filaments are not certified food-safe. TPU itself can be chemically inert once printed, but the additives (colorants, plasticizers) and the printing process (layer lines, potential microbial growth) make food-safe claims unreliable. Do not print food-contact items with standard TPU unless specifically certified.
How fast can I print TPU?
Soft TPU (85A–92A): 15–30 mm/s. Standard TPU (95A–98A): 30–60 mm/s with a well-tuned printer. Harder TPU formulations (60D+): 40–80 mm/s. Going faster than these ranges causes under-extrusion, stringing, and failed prints.
Does TPU need an enclosure?
No — TPU prints fine on open-frame printers. An enclosure is not needed and may actually cause issues by trapping heat, which can make the filament too soft in the extruder path. Room-temperature printing with controlled fan cooling works best.
How do I prevent TPU from stringing?
Dry the filament thoroughly (8+ hours at 45–55 °C). Reduce print speed. Minimize retraction or disable it entirely. Lower nozzle temperature by 5–10 °C. If stringing persists, TPU strings are usually easy to remove with a heat gun or by gentle scraping.
TPU opens up a whole category of functional prints that rigid materials cannot achieve. Start with a 95A Shore A TPU from Polymaker or Overture, slow your printer down to 20–30 mm/s, and make sure your filament is bone-dry before you start. The results will change how you think about 3D printing materials. Check our current deals on TPU filament to find the best prices on flexible spools for your next project.

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