3D Printing Info

Filament comparison

PET-CF vs PETG-GF

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

Carbon-fibre PET (PET-CF) guideGlass-fibre polyester (PETG-GF / PET-GF) guide

2 selected · all documented properties

Open these two in the interactive comparisonMore PET-CF comparisonsMore PETG-GF comparisons
PET-CF vs PETG-GF — documented properties and sources
PropertyCarbon-fibre PET (PET-CF)PETGGlass-fibre polyester (PETG-GF / PET-GF)PETG
Market snapshot
Listing priceUSD/kg; dated snapshots$39.99/kg median; $26.00–$49.98/kg across 4 dated product listings$27.38/kg median; $18.99–$29.99/kg across 3 dated product listings
Identity & Market
Base polymer / chemistrySemi-crystalline PET reinforced with carbon fibre — a different polymer from PETG-CF, with the glycol modifier removed so the matrix can crystallise[1][2]Glass-fibre reinforced polyester. Polymaker's Fiberon PET-GF15 uses a PET rather than a PETG matrix and carries 15 wt% glass fibre[3]
Densityg/cm³1.29 (Bambu Lab) and 1.34 (Fiberon PET-CF17), ISO 1183[1][2]1.43 (Fiberon PET-GF15, ISO 1183)[3]
Typical priceUSD/kg1 kg spools cluster near 45[1][4]1 kg spools cluster near 25[5][4]
Price range across brandsUSD/kg26–50 across brands; ELEGOO 26 in a 5 kg pack, Bambu Lab 45, Fiberon 50[5][1][4]19–30 across brands; ELEGOO 19, Polymaker Fiberon 30[5][4]
Market availability1–5Available from several mainstream brands[1][4][5]Niche, a handful of specialist brands[5][4]
Spool sizes & diameters1.75 mm; 0.5 and 1 kg spools[4][1]1.75 mm; 0.5 and 1 kg spools[4]
Typical applicationsLoad-bearing parts that must survive above PETG's 70 °C ceiling without moving to PA or PC[1][2]Stiff, dimensionally stable fixtures; the Fiberon grade is designed to be annealed for heat resistance[3]
Printing Parameters
Nozzle temperature°C260–290 (Bambu Lab)[1]Not documented
Bed temperature°C80–100 (Bambu Lab)[1]Not documented
Enclosure / chamber requirement1–5Enclosure recommended — Bambu Lab specifies a 45–60 °C chamber[1]Not documented
Recommended chamber temperature°C45–60 (Bambu Lab)[1]Not documented
Part cooling fan0–60 % (Bambu Lab)[1]Not documented
Bed surface & adhesion aidTextured PEI, satin or powder-coated sheets; on smooth PEI a glue stick acts as a release agent[6][7]Textured PEI, satin or powder-coated sheets; on smooth PEI a glue stick acts as a release agent[6][7]
Maximum volumetric flow (mm³/s; see test conditions)mm³/s8 at Bambu Lab's 100 mm/s cap on a 0.4 mm nozzle at 0.2 mm layer — half the speed it allows for PETG-CF[1][8]Not documented
Bed-adhesion difficulty1–5Needs the right surface or a thin adhesive — the problem is releasing the part, not sticking it[6][7]Needs the right surface or a thin adhesive — the problem is releasing the part, not sticking it[6][7]
Stringing / oozing tendency1–5Moderate — retraction tuning needed; Polymaker names stringing as PETG's common quirk[7]Moderate — retraction tuning needed; Polymaker names stringing as PETG's common quirk[7]
Overall printing difficulty1–5Advanced — enclosure, hardware upgrades, tuning[1]Not documented
Hardware Wear & Reliability
Nozzle hardness required1–4Hardened steel required[1]Hardened steel required[3]
Abrasiveness1–5Highly abrasive — standard CF composite[1]Highly abrasive — standard GF composite[3]
Nozzle clog risk1–5Moderate — needs dry filament and a clean nozzle; Prusa lists higher risk of nozzle clogging for carbon-filled composites[9]Moderate — needs dry filament and a clean nozzle; Prusa lists higher risk of nozzle clogging for glass-filled composites[9]
Heat-creep / jam sensitivity1–5Slightly sensitive[10]Slightly sensitive[10]
Hotend requirementNo special hot-end required[10]No special hot-end required[10]
Moisture Behaviour
Moisture absorption (hygroscopicity)1–5Moderate — 0.37 % saturated at 25 °C / 55 % RH (Bambu Lab); 0.53 % equilibrium (Fiberon)[1][2]Moderate (0.3–0.8 %) — the PETG matrix reaches 0.40 % saturated at 25 °C / 55 % RH; no glass-filled grade publishes its own figure[6]
Equilibrium moisture content at ~50 % RH%0.37 saturated at 25 °C / 55 % RH (Bambu Lab); 0.53 equilibrium (Fiberon PET-CF17)[1][2]Not documented
Drying temperature & time80 °C for 8–12 h (Bambu Lab) — the longest and hottest dry in the polyester family; Fiberon specifies 100 °C for 10 h[1][2]Not documented
Symptoms when wetBubbling and popping at the nozzle, stringing and a rough surface[11]Bubbling and popping at the nozzle, stringing and a rough surface[11]
Effect of moisture on strengthBambu Lab publishes its whole mechanical table under the heading "Mechanical Properties (Dry state)" — the quoted figures apply only to dried filament[1]Polymaker 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[11]
Storage requirementSealed with desiccant; Polymaker groups PETG with the highly hygroscopic materials[11][7]Sealed with desiccant; Polymaker groups PETG with the highly hygroscopic materials[11][7]
Hydrolysis at melt temperatureThe 80–100 °C dry both suppliers mandate is far above the 55–65 °C used for PETG, consistent with a melt-hydrolysis risk in the semi-crystalline PET matrix; neither publishes a molecular-weight loss figure[1][2]Not documented
Mechanical Properties
Tensile strength (XY)MPa65.9 (Fiberon) to 74 (Bambu Lab) printed XY, ISO 527[1][2]59.9 ± 0.8 printed XY, ISO 527 (Fiberon PET-GF15)[3]
Young's modulusMPa4730 ± 260 (Bambu Lab) and 5481 ± 224 (Fiberon) printed XY, ISO 527[1][2]4144 ± 133 printed XY, ISO 527 (Fiberon PET-GF15)[3]
Elongation at break%2.4 ± 0.5 printed XY, ISO 527 (Fiberon PET-CF17)[2]4.0 ± 0.5 printed XY, ISO 527 (Fiberon PET-GF15)[3]
Flexural strengthMPa109.3 ± 2.0 printed XY, ISO 178 (Fiberon PET-CF17)[2]104.2 ± 2.4 printed XY, ISO 178 (Fiberon PET-GF15)[3]
Flexural modulusMPa4744 ± 136 printed XY, ISO 178 (Fiberon PET-CF17)[2]3705 ± 85 printed XY, ISO 178 (Fiberon PET-GF15)[3]
Charpy impact, notchedkJ/m²5.1 ± 0.2 printed XY, ISO 179 notched (Fiberon PET-CF17); unnotched 25.1 ± 2.8[2]8.7 ± 0.6 printed XY, ISO 179, notched (Fiberon PET-GF15)[3]
Other impact dataNot documentedCharpy unnotched 27.2 ± 2.0 printed XY (Fiberon PET-GF15, ISO 179)[3]
Layer adhesion / Z tensileMPa27.9 (Fiberon) and 35 ± 5 (Bambu Lab) printed Z, ISO 527[1][2]48.2 ± 0.3 printed Z, ISO 527 (Fiberon PET-GF15)[3]
Brittleness1–5Very brittle — elongation at break 2.4 % in XY and 0.8 % in Z[2]Brittle — snaps with little warning; elongation 4.0 % in XY and 2.6 % in Z[3]
Creep resistance / sustained load1–5Good — no creep test found; annealed PET-CF holds a 105 °C HDT at 1.8 MPa and a 4730–5481 MPa modulus against 1500–2311 for PETG[2][1]Below average — no GF-grade creep test; the CF grades sagged to 14.8–16.7 mm over 5 days at 1.25 kg against 17.1–20.4 mm unfilled[12][13][14]
Fatigue / repeated-flex resistance1–5Below average — no S-N curve; elongation at break is 2.4 % in XY and 0.8 % in Z, against 5.2–9.3 % for unfilled PETG[2]Below average — no GF-grade S-N curve; elongation at break falls to 4.0 % in XY against 5.2–9.3 % unfilled[3][15]
Elasticity / flexibility1–5Rigid[1]Rigid[3]
Z strength as % of XY%42 (Fiberon) to 47 (Bambu Lab), printed[1][2]80 (Fiberon PET-GF15, printed Z against XY tensile)[3]
Thermal Properties
HDT at 0.45 MPa°C147.5 (Fiberon) and 205 (Bambu Lab), ISO 75 at 0.45 MPa[1][2]81.6 as printed, 133.7 after annealing (ISO 75, 0.45 MPa)[3]
HDT at 1.8 MPa°C105 (Fiberon) and 182 (Bambu Lab), ISO 75 at 1.8 MPa[1][2]71.8 as printed, 87.3 after annealing (ISO 75, 1.8 MPa)[3]
Glass transition (Tg)°C75 (Bambu Lab) and 79.3 (Fiberon), DSC[1][2]59.5 (DSC)[3]
Melting point / Vicat°C241.3 (Fiberon) and 250 (Bambu Lab) melting, DSC; Vicat 226–238[1][2]231.6 melting (DSC); Vicat 232.6 (ISO 306)[3]
Annealing responseThe PET matrix crystallises on annealing, which is what separates this grade from PETG-CF[2][1]Annealing lifts HDT at 0.45 MPa from 81.6 to 133.7 °C[3]
Thermal expansion (CTE)µm/m·KNot documented20 along the print bead and 63–74 in the build direction at 30 °C (30 wt% GF, large-format printed, TMA)[16]
Flammability / UL 94Flammable; no UL 94 rating published for standard grades[17]UL 94 HB at 1.5 mm (Fiberon PET-GF15)[3]
Environment & Chemical
Chemical resistanceWithstands acids, alkalis, oils and UV exposure[7]Withstands acids, alkalis, oils and UV exposure[7]
Food contactNot certified for food contact as filament[7]Not certified for food contact as filament[7]
Biodegradability / compostabilityNot biodegradable[7]Not biodegradable[7]
RecyclabilityNot accepted in household plastic collection[7]Not accepted in household plastic collection[7]
Electrical & ESD propertiesSurface resistivity above 10¹² ohm — insulating (Fiberon PET-CF17, ANSI/ESD S11.11)[2]Surface resistivity above 10¹² ohm — insulating (Fiberon PET-GF15, ANSI/ESD S11.11)[3]
Health & Safety
Fume toxicity1–5Moderate — measurable VOCs and UFPs, ventilation advised[18]Moderate — measurable VOCs and UFPs, ventilation advised[18]
Ventilation / filtration requirement1–5Ventilated room or enclosure recommended[18][1]Open a window / occasional ventilation[18]
Dust & fibre handling hazardCarbon fibre is bound in the matrix; sanding dust should not be inhaled[2]Glass fibre is bound in the matrix; avoid inhaling sanding dust[3]
Post-Processing
Sanding & machiningSands poorly — the material is tough and gums rather than powders[10]Sands poorly — the material is tough and gums rather than powders[10]
Gluing & solvent weldingCyanoacrylate; no common solvent welds PETG cleanly[10]Cyanoacrylate; no common solvent welds PETG cleanly[10]
Vapour / chemical smoothingNo practical vapour smoothing[10]No practical vapour smoothing[10]
Support material pairingPrints its own supports; Polymaker rates PolyDissolve S1 for PETG[10]Prints its own supports; Polymaker rates PolyDissolve S1 for PETG[10]
Dimensional accuracy & detailBambu Lab markets it on low warping and shrinkage relative to other high-temperature composites[1]Not documented
Solvents & Solubility
Soluble inNone common; fluorinated solvents such as hexafluoroisopropanol dissolve linear polyester at 23 °C. Laboratory only.[19][20]No common workshop solvent; dichloromethane — a carcinogen — dissolves the matrix surface, 1,2-dichloroethane destroys it in a week.[21][22]
Softened or crazed byEnsinger rates polyester not resistant to chloroform or dichloromethane and only conditionally resistant to acetone and MEK.[20]Acetone (+16 % weight over 1 year at 23 °C), ethyl acetate, toluene and DMF swell and soften it; methanol crazes it.[21]
Solvent welding & smoothing agentDichloromethane attacks polyester and can be brushed on, but the carbon fibre blocks any useful surface flow.[20][22]Dichloromethane reaches only the resin, so the fibre is left standing proud of the surface. Controlled carcinogen.[22]

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. Bambu Filament Technical Data Sheet — PET-CF Bambu Lab · 2026-08 · tds
  2. Fiberon PET-CF17 Technical Data Sheet V1.0 Polymaker · 2026-08 · tds
  3. Fiberon PET-GF15 Technical Data Sheet V1.0 Polymaker · 2026-08 · tds
  4. Polymaker product catalogue Polymaker · 2026-08 · vendor
  5. ELEGOO product catalogue ELEGOO · 2026-08 · vendor
  6. Prusament PETG Technical Datasheet v1.1 Prusa Polymers · 2022-02 · tds
  7. PETG — material basics Polymaker Wiki · 2026-08 · doc
  8. Max volumetric speed Prusa Knowledge Base · 2026-08 · doc
  9. Composite materials filled with carbon, kevlar or glass Prusa Knowledge Base · 2026-08 · doc
  10. PET and PETG — Ultimate 3D Printing Materials Guide Simplify3D · 2026-08 · doc
  11. Wet Filament — signs, causes and drying Polymaker Wiki · 2026-08 · doc
  12. Extrudr PETG vs PCTG vs XPETG-CF — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  13. Prusament PETG-CF vs PETG V0 vs PETG — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  14. BambuLab PETG Basic vs Translucent vs PETG-CF — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  15. Mechanical Properties of Additively Manufactured Polymeric Materials — PLA and PETG — For Biomechanical Applications Polymers 16(13):1868 · 2024-06 · paper
  16. Effects of Fiber Orientation on the Coefficient of Thermal Expansion of Fiber-Filled Polymer Systems in Large Format Polymer Extrusion-Based Additive Manufacturing Materials 15(8):2764 · 2022-04 · paper
  17. Prusament PETG V0 Technical Datasheet Prusa Polymers · 2026-08 · tds
  18. 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
  19. Resistance of Ultramid, Ultraform and Ultradur to chemicals (TI-KTU/AS-28 e) BASF · 2000-10 · tds
  20. Chemical resistance — resistance of Ensinger plastics to chemicals (DIN 50 014, 23/50) Ensinger · 2026-08 · tds
  21. Eastman Spectar copolyester — Chemical resistance (unstressed bars, 1 year at 23 °C) Eastman Chemical Company · 2026-08 · tds
  22. Improve your 3D prints with chemical smoothing Prusa Research · 2026-08 · doc