3D Printing Info

Filament comparison

rPETG vs TPU soft

Compare printing settings, strength, heat resistance, dated prices and sources.

Recycled PETG (rPETG) guideSoft TPU (below 85A) guide

2 selected · all documented properties

Open these two in the interactive comparisonMore rPETG comparisonsMore TPU soft comparisons
rPETG vs TPU soft — documented properties and sources
PropertyRecycled PETG (rPETG)PETGSoft TPU (below 85A)FLEX
Market snapshot
Listing priceUSD/kg; dated snapshots$28.99/kg median; $17.24–$39.98/kg across 4 dated product listings$114.04/kg median; $109.80–$122.27/kg across 4 dated product listings
Identity & Market
Base polymer / chemistryPETG regranulated from recycled polyester waste; Polymaker's Fiberon PETG-rCF08 adds 8 wt% recycled carbon fibre[1][2][3]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[4]
Densityg/cm³1.27 (Prusament) and 1.30 (Fiberon PETG-rCF08), ISO 1183[1][3]1.07 (Fiberlogy FiberFlex 30D, ISO 1183)[4]
Typical priceUSD/kg1 kg spools cluster near 29[5][6][7][8]1 kg-equivalent spools cluster near 115[9][10][11]
Price range across brandsUSD/kg17–40 across brands; Filament PM RePETG 17, 3DXTech ECOMAX 26, GreenGate3D 32, Fiberon rCF08 40[5][6][7][8]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[9][11][10]
Market availability1–5Available from several mainstream brands[5][6][7]Niche, a handful of specialist brands[4][12][9]
Spool sizes & diameters1.75 and 2.85 mm; 0.5, 1 and 3 kg spools[7][6]1.75, 2.85 and 3 mm; 0.5, 0.85, 1, 2 and 3 kg spools[4][9][13][10]
Typical applicationsNot documentedHighly compliant seals, soft grips and prosthetic liners[4]
Diameter tolerance± mm±0.05 (Prusament PETG Recycled), against ±0.02 for virgin Prusament PETG[1][14]Not documented
Printing Parameters
Nozzle temperature°C250 ± 10 (Prusament); 230–255 (Spectrum)[1][2]Not documented
Bed temperature°C80 ± 10 (Prusament); 60–80 (Spectrum)[1][2]50–70 (Fiberlogy FiberFlex 30D)[4]
Enclosure / chamber requirement1–5Open frame is fine — Spectrum states a closed chamber is not necessary[2]Open frame is fine[4]
Part cooling fan50 % (Prusament); up to 100 % (Spectrum)[1][2]Not documented
Bed surface & adhesion aidTextured PEI, satin or powder-coated sheets; on smooth PEI a glue stick acts as a release agent[14][15]PEI sheet or painter's tape; Polymaker warns TPU can over-stick and advises a glue stick as a release agent[16][17]
Bed-adhesion difficulty1–5Needs the right surface or a thin adhesive — the problem is releasing the part, not sticking it[14][15]Not documented
Stringing / oozing tendency1–5Moderate — retraction tuning needed; Polymaker names stringing as PETG's common quirk[15]Not documented
Overall printing difficulty1–5Easy — minor profile tuning; Spectrum describes printing as similar to standard PETG[2]Expert / industrial hardware only — below 85 Shore A the filament buckles in almost any feed path that is not a short, constrained direct drive[13][17]
Extruder requirementNot documentedDirect drive only, with a constrained filament path; Bowden is not viable at this hardness[13][12]
Hardware Wear & Reliability
Nozzle hardness required1–4Brass fine indefinitely[1]Brass fine indefinitely[18]
Abrasiveness1–5Not documentedNon-abrasive[18]
Nozzle clog risk1–5Low — recycled PETG prints on the same hardware as virgin PETG: no special hot-end, no drybox and no hardened nozzle[19][20]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[16][17][21]
Heat-creep / jam sensitivity1–5Slightly sensitive[19]Very high — softens in the cold zone readily[17]
Hotend requirementNo special hot-end required[19]No special hot-end required, but a direct-drive extruder is (Simplify3D)[16]
Moisture Behaviour
Moisture absorption (hygroscopicity)1–5Moderate (0.3–0.8 %) — recycled PETG shares the virgin matrix, which reaches 0.40 % saturated at 25 °C / 55 % RH[14]Moderate[21]
Equilibrium moisture content at ~50 % RH%0.07 after 24 h and 0.10 after 7 days at 24 °C / 22 % RH (Prusa Polymers)[1]Not documented
Symptoms when wetBubbling and popping at the nozzle, stringing and a rough surface[21]Bubbling and popping at the nozzle, stringing and a rough surface[21]
Effect of moisture on strengthPolymaker groups PETG with nylon, PVA and TPU as highly hygroscopic; no dry-versus-conditioned strength figures are published for this grade and the loss shows as bubbling and poor layer adhesion[21]Polymaker groups TPU with the highly hygroscopic materials; no dry-versus-conditioned figures are published[21]
Storage requirementSealed with desiccant; Polymaker groups PETG with the highly hygroscopic materials[21][15]Sealed with desiccant; often kept in a dryer during the print[21]
Mechanical Properties
Tensile strength (XY)MPa43 ± 1.8 printed horizontal at yield, ISO 527-1 (Prusament), against 47 ± 2 for virgin Prusament PETG; Spectrum quotes 52 at yield on moulded specimens[1][14][2]Not documented
Young's modulusMPa1500 printed horizontal, 1600 printed vertical (Prusament, ISO 527-1) — the same as virgin Prusament PETG[1][14]Not documented
Elongation at break%4.5 at yield printed (Prusament); Spectrum quotes 400 at break on moulded specimens[1][2]870 at break (Fiberlogy FiberFlex 30D, ISO 527) — the highest elongation in the dataset[4]
Flexural strengthMPa63 ± 1 printed horizontal, ISO 178 (Prusament), against 66 ± 2 for virgin Prusament PETG[1][14]Not documented
Flexural modulusMPa1800 printed horizontal, ISO 178 (Prusament)[1]Not documented
Charpy impact, notchedkJ/m²12 ± 1 printed horizontal and 15 ± 3 printed vertical, ISO 179-1 notched (Prusament)[1]Not documented
Other impact dataCharpy unnotched 25 ± 3 printed horizontal and 38 ± 11 printed vertical (Prusament, ISO 179-1)[1]Not documented
Layer adhesion / Z tensileMPa15 ± 5 (Prusa Polymers interlayer adhesion test), against 18 ± 4 for virgin Prusament PETG[1][14]Not documented
Brittleness1–5Moderate[1]Very ductile — bends far before failing[4]
Hardness (scale-specific)Shore A / Shore D / Rockwell74 Shore D (Prusa Polymers method) — the same as virgin Prusament PETG[1][14]81 Shore A and 30 Shore D (Fiberlogy FiberFlex 30D, ISO 7619)[4]
Creep resistance / sustained load1–5Below average — no recycled-grade creep test; virgin PETG sagged from 12 to 17.1–20.4 mm over 5 days at 1.25 kg[22][23][24][25]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[26]
Fatigue / repeated-flex resistance1–5Moderate — no recycled-grade S-N curve; virgin printed PETG ran 79 000–193 000 cycles at 30 % of tensile strength[27]Excellent — living hinges viable[17]
Elasticity / flexibility1–5Slightly flexible in thin sections[1]Rubbery / highly elastic[4]
Wear resistance & frictionNot documentedTear strength 95 kN/m (Fiberlogy FiberFlex 30D, ISO 34-1)[4]
Thermal Properties
HDT at 0.45 MPa°C68 (ISO 75, 0.45 MPa) — the same as virgin Prusament PETG; Spectrum quotes 70[1][14][2]Not documented
HDT at 1.8 MPa°C68 (ISO 75, 1.8 MPa)[1]Not documented
Melting point / Vicat°CNot documented170 melting (Fiberlogy FiberFlex 30D, DSC)[4]
Flammability / UL 94Flammable; no UL 94 rating published for standard grades[28]Not documented
Environment & Chemical
UV resistance1–5Not documentedGood — years with some colour shift; Polymaker lists UV exposure among the conditions TPU withstands[17]
Chemical resistanceWithstands acids, alkalis, oils and UV exposure[15]Withstands industrial solvents and UV exposure (Polymaker)[17]
Food contactNot certified for food contact as filament[15]Not food safe without specific certification (Polymaker)[17]
Biodegradability / compostabilityNot biodegradable[15]Not biodegradable[17]
RecyclabilityThe feedstock itself — Spectrum describes collecting, shredding and re-homogenising PETG waste[2]Not accepted in household plastic collection[17]
Health & Safety
Fume toxicity1–5Moderate — measurable VOCs and UFPs, ventilation advised[29]Low hazard — minimal VOC and particle emission; TPU was not among the nine filaments in the chamber study[29]
Ventilation / filtration requirement1–5Open a window / occasional ventilation[29]Open a window / occasional ventilation[29]
Post-Processing
Sanding & machiningSands poorly — the material is tough and gums rather than powders[19]Difficult to sand or smooth; Polymaker limits post-processing to trimming or tumbling[17]
Gluing & solvent weldingCyanoacrylate; no common solvent welds PETG cleanly[19]Cyanoacrylate bonds TPU; no common solvent welds it[17]
Vapour / chemical smoothingNo practical vapour smoothing[19]No practical vapour smoothing[17]
Support material pairingPrints its own supports; Polymaker rates PolyDissolve S1 for PETG[19]Polymaker warns TPU supports are often very difficult to remove[17]
Solvents & Solubility
Soluble inNo common workshop solvent; 1,2-dichloroethane destroys it inside a week and dichloromethane — a carcinogen — dissolves the surface.[30][31]DMF, DMSO, NMP and THF dissolve TPU; acetone, MEK and cyclohexanone are partial solvents. All laboratory reagents.[32]
Softened or crazed byAcetone (+16 % weight over 1 year at 23 °C), ethyl acetate, toluene and DMF swell and soften it; methanol crazes it.[30]Toluene and benzene swell it up to +50 % by weight at 23 °C; esters swell it severely; ethanol and IPA soften it.[32]
Solvent welding & smoothing agentDichloromethane brushed on is the only agent that smooths PETG — a controlled carcinogen, not workshop stock.[31]None practical — the true solvents (DMF, THF, NMP) are laboratory reagents and leave the joint swollen and weak.[32]

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

  1. Prusament PETG Recycled Technical Datasheet Prusa Polymers · 2026-08 · tds
  2. Spectrum r-PETG Technical Data Sheet Spectrum Filaments · 2026-08 · tds
  3. Fiberon PETG-rCF08 Technical Data Sheet V1.0 Polymaker · 2026-08 · tds
  4. FiberFlex 30D Technical Data Sheet Fiberlogy · 2026-08 · tds
  5. 3DXTech product catalogue 3DXTech · 2026-08 · vendor
  6. GreenGate3D Recycled PET-G — product data GreenGate3D · 2026-08 · vendor
  7. Polymaker product catalogue Polymaker · 2026-08 · vendor
  8. Filament PM RePETG technical data sheet Filament PM (Plasty Mladec) · 2026-08 · tds
  9. Recreus product catalogue Recreus · 2026-08 · vendor
  10. Chinchilla product page — print guidelines, spool sizes and price NinjaTek · 2026-08 · vendor
  11. NinjaFlex Edge product page — durometer, print guidelines and price NinjaTek · 2026-08 · vendor
  12. Filaflex 82A product page (Shore hardness and elongation) Recreus · 2026-08 · vendor
  13. NinjaFlex 85A Technical Specifications NinjaTek · 2026-08 · tds
  14. Prusament PETG Technical Datasheet v1.1 Prusa Polymers · 2022-02 · tds
  15. PETG — material basics Polymaker Wiki · 2026-08 · doc
  16. Flexible (TPE/TPU) — Ultimate 3D Printing Materials Guide Simplify3D · 2026-08 · doc
  17. TPU — material basics Polymaker Wiki · 2026-08 · doc
  18. Extrudr Product Catalogue (DURAPRO PA12 data block) Extrudr · 2025-03 · tds
  19. PET and PETG — Ultimate 3D Printing Materials Guide Simplify3D · 2026-08 · doc
  20. Filament Material Guide Prusa Knowledge Base · 2026-08 · doc
  21. Wet Filament — signs, causes and drying Polymaker Wiki · 2026-08 · doc
  22. PCTG vs PETG comparison — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  23. Extrudr PETG vs PCTG vs XPETG-CF — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  24. Prusament PETG-CF vs PETG V0 vs PETG — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  25. BambuLab PETG Basic vs Translucent vs PETG-CF — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  26. BambuLab TPU 95A HF vs Qidi TPU 95A HF — results spreadsheet My Tech Fun (Igor Gaspar) · 2024-02 · test
  27. Mechanical Properties of Additively Manufactured Polymeric Materials — PLA and PETG — For Biomechanical Applications Polymers 16(13):1868 · 2024-06 · paper
  28. Prusament PETG V0 Technical Datasheet Prusa Polymers · 2026-08 · tds
  29. 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
  30. Eastman Spectar copolyester — Chemical resistance (unstressed bars, 1 year at 23 °C) Eastman Chemical Company · 2026-08 · tds
  31. Improve your 3D prints with chemical smoothing Prusa Research · 2026-08 · doc
  32. Elastollan — Chemical properties: swelling and chemical resistance BASF · 2026-08 · tds