3D Printing InfoFilament comparison
TPU-CF vs TPU soft
Compare printing settings, strength, heat resistance, dated prices and sources.
2 selected · all documented properties
| Property | Carbon-fibre TPUFLEX | Soft TPU (below 85A)FLEX |
|---|---|---|
| Market snapshot | ||
| Listing priceUSD/kg; dated snapshots | $107.05/kg median; $107.05–$107.05/kg across 1 dated product listings | $114.04/kg median; $109.80–$122.27/kg across 4 dated product listings |
| Identity & Market | ||
| Base polymer / chemistry | Carbon-fibre reinforced thermoplastic polyurethane at the hard end of the range[1] | Very soft thermoplastic elastomers below 85 Shore A. Fiberlogy's FiberFlex 30D measures 81 Shore A, the softest grade with a published datasheet found here[2] |
| Densityg/cm³ | 1.22 (Extrudr FLEX HARD CF, ISO 2781)[1] | 1.07 (Fiberlogy FiberFlex 30D, ISO 1183)[2] |
| Typical priceUSD/kg | 107 for the only retail listing found (Extrudr 0.5 kg coil, incl. VAT)[3] | 1 kg-equivalent spools cluster near 115[4][5][6] |
| Price range across brandsUSD/kg | One listing only: EUR 49.56 incl. VAT per 0.5 kg coil, direct from Extrudr; no reseller or second brand found[3] | 110–122 at 1 kg-equivalent; Recreus 70A 110 and 60A 116 at 500 g, NinjaTek Edge 83A 112, NinjaTek Chinchilla 75A 122; the Recreus 3 kg spools fall to 70–73[4][6][5] |
| Market availability1–5 | Niche, a handful of specialist brands — Extrudr's FLEX HARD CF is the only carbon-filled flexible with a published datasheet found here[1] | Niche, a handful of specialist brands[2][7][4] |
| Spool sizes & diameters | 1.75 mm; 0.5 and 2 kg coils[3] | 1.75, 2.85 and 3 mm; 0.5, 0.85, 1, 2 and 3 kg spools[2][4][8][5] |
| Typical applications | Stiffened flexible parts — damping mounts and semi-rigid brackets[1] | Highly compliant seals, soft grips and prosthetic liners[2] |
| Printing Parameters | ||
| Nozzle temperature°C | 230–260 (Extrudr FLEX HARD CF)[1] | Not documented |
| Bed temperature°C | 50–90 (Extrudr FLEX HARD CF)[1] | 50–70 (Fiberlogy FiberFlex 30D)[2] |
| Enclosure / chamber requirement1–5 | Open frame is fine[1] | Open frame is fine[2] |
| Bed surface & adhesion aid | PEI sheet or painter's tape; Polymaker warns TPU can over-stick and advises a glue stick as a release agent[9][10] | PEI sheet or painter's tape; Polymaker warns TPU can over-stick and advises a glue stick as a release agent[9][10] |
| Maximum volumetric flow (mm³/s; see test conditions)mm³/s | 1.6–8 at the 20–100 mm/s Extrudr specifies on a 0.4 mm nozzle at 0.2 mm layer[1] | Not documented |
| Overall printing difficulty1–5 | Advanced — enclosure, hardware upgrades, tuning; hardened nozzle needed[1] | Expert / industrial hardware only — below 85 Shore A the filament buckles in almost any feed path that is not a short, constrained direct drive[8][10] |
| Extruder requirement | Not documented | Direct drive only, with a constrained filament path; Bowden is not viable at this hardness[8][7] |
| Hardware Wear & Reliability | ||
| Nozzle hardness required1–4 | Hardened steel required — Extrudr marks FLEX HARD CF as needing a hardened nozzle where its unfilled FLEX grades do not[1] | Brass fine indefinitely[1] |
| Abrasiveness1–5 | Highly abrasive — standard CF composite[1] | Non-abrasive[1] |
| Nozzle clog risk1–5 | High — jams from moisture, heat creep or particles; a flexible base plus chopped carbon fibre, which Prusa lists as a higher nozzle-clogging risk, and Extrudr requires a hardened nozzle[11][1][9] | High — jams from moisture, heat creep or particles; below 85 Shore A the filament buckles and compresses, and Simplify3D warns that raised feed rates most likely end in a jam[9][10][12] |
| Heat-creep / jam sensitivity1–5 | Not documented | Very high — softens in the cold zone readily[10] |
| Hotend requirement | No special hot-end required, but a direct-drive extruder is (Simplify3D)[9] | No special hot-end required, but a direct-drive extruder is (Simplify3D)[9] |
| Moisture Behaviour | ||
| Moisture absorption (hygroscopicity)1–5 | Moderate[12] | Moderate[12] |
| Drying temperature & time | 60 °C for 6 h (Extrudr FLEX HARD CF)[1] | Not documented |
| Symptoms when wet | Bubbling and popping at the nozzle, stringing and a rough surface[12] | Bubbling and popping at the nozzle, stringing and a rough surface[12] |
| Effect of moisture on strength | Polymaker groups TPU with the highly hygroscopic materials; no dry-versus-conditioned figures are published[12] | Polymaker groups TPU with the highly hygroscopic materials; no dry-versus-conditioned figures are published[12] |
| Storage requirement | Sealed with desiccant; often kept in a dryer during the print[12] | Sealed with desiccant; often kept in a dryer during the print[12] |
| Mechanical Properties | ||
| Young's modulusMPa | 35 (Extrudr FLEX HARD CF, ISO 527-2/5A/500)[1] | Not documented |
| Elongation at break% | 380 ultimate elongation (Extrudr FLEX HARD CF, ISO 527-2/5A/500), against 490 for the unfilled FLEX HARD[1] | 870 at break (Fiberlogy FiberFlex 30D, ISO 527) — the highest elongation in the dataset[2] |
| Brittleness1–5 | Very ductile — bends far before failing[1] | Very ductile — bends far before failing[2] |
| Hardness (scale-specific)Shore A / Shore D / Rockwell | 70 Shore D (Extrudr FLEX HARD CF, ISO 868), against 58 Shore D for the unfilled FLEX HARD[1] | 81 Shore A and 30 Shore D (Fiberlogy FiberFlex 30D, ISO 7619)[2] |
| Creep resistance / sustained load1–5 | Below average — no CF-grade creep test; the grade is 70 Shore D where a 95A TPU bar crept from 74.5 to 82.7 mm over 5 days at 1.25 kg[1][13] | Poor — no creep test at this hardness; a printed 95A TPU bar crept from 74.5 to 82.7 mm over 5 days at 1.25 kg[13] |
| Fatigue / repeated-flex resistance1–5 | Good — 380 % ultimate elongation and a damping application set (Extrudr cites longboard wheels), below the unfilled grades[1] | Excellent — living hinges viable[10] |
| Elasticity / flexibility1–5 | Semi-flexible[1] | Rubbery / highly elastic[2] |
| Wear resistance & friction | Abrasion 26 mm³ (Extrudr FLEX HARD CF, ISO 4649-A) — the same as the unfilled FLEX HARD[1] | Tear strength 95 kN/m (Fiberlogy FiberFlex 30D, ISO 34-1)[2] |
| Thermal Properties | ||
| Glass transition (Tg)°C | -24 (Extrudr FLEX HARD CF)[1] | Not documented |
| Melting point / Vicat°C | Vicat A 140 (Extrudr FLEX HARD CF, ISO 306)[1] | 170 melting (Fiberlogy FiberFlex 30D, DSC)[2] |
| Environment & Chemical | ||
| UV resistance1–5 | Good — years with some colour shift; Polymaker lists UV exposure among the conditions TPU withstands[10] | Good — years with some colour shift; Polymaker lists UV exposure among the conditions TPU withstands[10] |
| Chemical resistance | Withstands industrial solvents and UV exposure (Polymaker)[10] | Withstands industrial solvents and UV exposure (Polymaker)[10] |
| Food contact | Not food safe without specific certification (Polymaker)[10] | Not food safe without specific certification (Polymaker)[10] |
| Biodegradability / compostability | Not biodegradable[10] | Not biodegradable[10] |
| Recyclability | Not accepted in household plastic collection[10] | Not accepted in household plastic collection[10] |
| Health & Safety | ||
| Fume toxicity1–5 | Low hazard — minimal VOC and particle emission; TPU was not among the nine filaments in the chamber study[14] | Low hazard — minimal VOC and particle emission; TPU was not among the nine filaments in the chamber study[14] |
| Ventilation / filtration requirement1–5 | Open a window / occasional ventilation[14] | Open a window / occasional ventilation[14] |
| Dust & fibre handling hazard | Carbon fibre is bound in the matrix; sanding dust should not be inhaled[1] | Not documented |
| Post-Processing | ||
| Sanding & machining | Difficult to sand or smooth; Polymaker limits post-processing to trimming or tumbling[10] | Difficult to sand or smooth; Polymaker limits post-processing to trimming or tumbling[10] |
| Gluing & solvent welding | Cyanoacrylate bonds TPU; no common solvent welds it[10] | Cyanoacrylate bonds TPU; no common solvent welds it[10] |
| Vapour / chemical smoothing | No practical vapour smoothing[10] | No practical vapour smoothing[10] |
| Support material pairing | Polymaker warns TPU supports are often very difficult to remove[10] | Polymaker warns TPU supports are often very difficult to remove[10] |
| Dimensional accuracy & detail | Tear strength 165 kN/m (Extrudr FLEX HARD CF, ISO 34-1B)[1] | Not documented |
| Solvents & Solubility | ||
| Soluble in | DMF, DMSO, NMP and THF dissolve the TPU matrix and leave the fibre; ketones are partial solvents. Laboratory reagents.[15] | DMF, DMSO, NMP and THF dissolve TPU; acetone, MEK and cyclohexanone are partial solvents. All laboratory reagents.[15] |
| Softened or crazed by | Toluene and benzene swell it up to +50 % by weight at 23 °C; esters swell it severely; ethanol and IPA soften it.[15] | Toluene and benzene swell it up to +50 % by weight at 23 °C; esters swell it severely; ethanol and IPA soften it.[15] |
| Solvent welding & smoothing agent | None practical — the true solvents (DMF, THF, NMP) are laboratory reagents and leave the joint swollen and weak.[15] | None practical — the true solvents (DMF, THF, NMP) are laboratory reagents and leave the joint swollen and weak.[15] |
Material entries describe families or representative grades, not an interchangeable specification for every spool. Test methods, orientations and conditions may differ. Unknown values are marked “Not documented”. Prices and source dates remain historical snapshots; check the linked guide for product details. Differences highlight text, not a universal winner.
Sources for this comparison
- Extrudr Product Catalogue (DURAPRO PA12 data block) Extrudr · 2025-03 · tds
- FiberFlex 30D Technical Data Sheet Fiberlogy · 2026-08 · tds
- Extrudr TPU FLEX Hard CF — product page (1.75 mm, 0.5 and 2 kg coils, price) Extrudr (FD3D GmbH) · 2026-08 · vendor
- Recreus product catalogue Recreus · 2026-08 · vendor
- Chinchilla product page — print guidelines, spool sizes and price NinjaTek · 2026-08 · vendor
- NinjaFlex Edge product page — durometer, print guidelines and price NinjaTek · 2026-08 · vendor
- Filaflex 82A product page (Shore hardness and elongation) Recreus · 2026-08 · vendor
- NinjaFlex 85A Technical Specifications NinjaTek · 2026-08 · tds
- Flexible (TPE/TPU) — Ultimate 3D Printing Materials Guide Simplify3D · 2026-08 · doc
- TPU — material basics Polymaker Wiki · 2026-08 · doc
- Composite materials filled with carbon, kevlar or glass Prusa Knowledge Base · 2026-08 · doc
- Wet Filament — signs, causes and drying Polymaker Wiki · 2026-08 · doc
- BambuLab TPU 95A HF vs Qidi TPU 95A HF — results spreadsheet My Tech Fun (Igor Gaspar) · 2024-02 · test
- Emissions of Ultrafine Particles and Volatile Organic Compounds from Commercially Available Desktop Three-Dimensional Printers with Multiple Filaments (Azimi et al.) Environmental Science & Technology 50(3) 1260-1268 · 2016-01 · paper
- Elastollan — Chemical properties: swelling and chemical resistance BASF · 2026-08 · tds