3D Printing Info

Filament comparison

PETG-CF vs PETG-GF

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

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

2 selected · all documented properties

Open these two in the interactive comparisonMore PETG-CF comparisonsMore PETG-GF comparisons
PETG-CF vs PETG-GF — documented properties and sources
PropertyCarbon-fibre PETG (PETG-CF)PETGGlass-fibre polyester (PETG-GF / PET-GF)PETG
Market snapshot
Listing priceUSD/kg; dated snapshots$29.99/kg median; $16.00–$74.22/kg across 11 dated product listings$27.38/kg median; $18.99–$29.99/kg across 3 dated product listings
Identity & Market
Base polymer / chemistryPETG reinforced with chopped carbon fibre[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/cm³1.25 (Bambu Lab) to 1.34 (3DXTech), ISO 1183; Prusament 1.27[1][4][2]1.43 (Fiberon PET-GF15, ISO 1183)[3]
Typical priceUSD/kg1 kg-equivalent spools span 16–74; the middle of the market is about 29[1][5][6][7][8][9][10][11]1 kg spools cluster near 25[12][13]
Price range across brandsUSD/kg16–74 across brands; ELEGOO 16 in a 5 kg pack, Reli3D 17, SUNLU 20, IEMAI 22, Siraya Tech 25, Bambu Lab 32, Sakata 3D 53, 3DXTech 67, Prusament 70, Filament PM 74 on 0.5 kg spools[12][1][14][5][6][7][8][9][10][11]19–30 across brands; ELEGOO 19, Polymaker Fiberon 30[12][13]
Market availability1–5Stocked by most mainstream brands[1][14][5][12]Niche, a handful of specialist brands[12][13]
Spool sizes & diameters1.75 and 2.85 mm; 0.75 and 1 kg spools[14][1]1.75 mm; 0.5 and 1 kg spools[13]
Typical applicationsStiff functional parts and fixtures where PETG's toughness is traded for rigidity and a matte finish[1][2]Stiff, dimensionally stable fixtures; the Fiberon grade is designed to be annealed for heat resistance[3]
Diameter tolerance± mm±0.02 (Prusament)[2]Not documented
Printing Parameters
Nozzle temperature°C240–270 (Bambu Lab); 265 ± 10 (Prusament)[1][2]Not documented
Bed temperature°C65–75 (Bambu Lab); 90 ± 10 (Prusament)[1][2]Not documented
Enclosure / chamber requirement1–5Open frame fine; draught shield helps — Bambu Lab specifies a 35–50 °C chamber[1]Not documented
Recommended chamber temperature°C35–50 (Bambu Lab)[1]Not documented
Part cooling fan0–60 % (Bambu Lab); 50 % (Prusament)[1][2]Not documented
Bed surface & adhesion aidTextured PEI or engineering plate with glue (Bambu Lab)[1]Textured PEI, satin or powder-coated sheets; on smooth PEI a glue stick acts as a release agent[15][16]
Maximum volumetric flow (mm³/s; see test conditions)mm³/s11.5 on My Tech Fun's Bambu Lab PETG-CF profile[17]Not documented
Bed-adhesion difficulty1–5Needs the right surface or a thin adhesive[1]Needs the right surface or a thin adhesive — the problem is releasing the part, not sticking it[15][16]
Stringing / oozing tendency1–5Slight — the fibre reduces stringing against unfilled PETG[1][18]Moderate — retraction tuning needed; Polymaker names stringing as PETG's common quirk[16]
Overall printing difficulty1–5Intermediate — dry filament and a tuned profile; hardened nozzle mandatory[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; 3DXTech specifies a hardened 0.4 mm minimum nozzle and 0.25 mm layers or higher, and Prusa lists composites as a higher clogging risk[19][20]Moderate — needs dry filament and a clean nozzle; Prusa lists higher risk of nozzle clogging for glass-filled composites[20]
Heat-creep / jam sensitivity1–5Slightly sensitive[18]Slightly sensitive[18]
Hotend requirementHardened steel nozzle; no high-temperature hot-end needed[1][18]No special hot-end required[18]
Moisture Behaviour
Moisture absorption (hygroscopicity)1–5Low — 0.30 % saturated at 25 °C / 55 % RH (Bambu Lab)[1]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[15]
Equilibrium moisture content at ~50 % RH%0.30 saturated at 25 °C / 55 % RH (Bambu Lab); Prusa measures 0.10 after 7 days at 22 % RH[1][2]Not documented
Drying temperature & time65 °C for 8 h (Bambu Lab)[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 strengthNo dry-versus-conditioned figures published; Bambu Lab states PETG-CF must be properly dried before printing and stored dry after use[1][21]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[21]
Storage requirementSealed with desiccant; Bambu Lab says store dry after use[1][21]Sealed with desiccant; Polymaker groups PETG with the highly hygroscopic materials[21][16]
Mechanical Properties
Tensile strength (XY)MPa35 ± 5 (Bambu Lab) and 47 ± 2 at yield (Prusament) printed XY, ISO 527; 56 at break for 3DXTech[1][2][4]59.9 ± 0.8 printed XY, ISO 527 (Fiberon PET-GF15)[3]
Young's modulusMPa2460 ± 230 (Bambu Lab) and 1700 (Prusament) printed XY, ISO 527[1][2]4144 ± 133 printed XY, ISO 527 (Fiberon PET-GF15)[3]
Elongation at break%4.3 at yield (Prusament, printed XY, ISO 527); 3 at break for 3DXTech[2][4]4.0 ± 0.5 printed XY, ISO 527 (Fiberon PET-GF15)[3]
Flexural strengthMPa68 ± 3 printed horizontal, ISO 178 (Prusament)[2]104.2 ± 2.4 printed XY, ISO 178 (Fiberon PET-GF15)[3]
Flexural modulusMPa2300 printed horizontal, 3100 printed vertical, ISO 178 (Prusament)[2]3705 ± 85 printed XY, ISO 178 (Fiberon PET-GF15)[3]
Charpy impact, notchedkJ/m²Not documented8.7 ± 0.6 printed XY, ISO 179, notched (Fiberon PET-GF15)[3]
Other impact dataCharpy unnotched 29 ± 6 printed horizontal and 43 ± 8 printed vertical (Prusament, ISO 179-1); Izod 4.91 kJ/m² on My Tech Fun bars[2][17]Charpy unnotched 27.2 ± 2.0 printed XY (Fiberon PET-GF15, ISO 179)[3]
Layer adhesion / Z tensileMPa29 ± 4 printed Z (Bambu Lab, ISO 527); 18 ± 3 by Prusa's interlayer adhesion test; 10.7 on My Tech Fun bars[1][2][17]48.2 ± 0.3 printed Z, ISO 527 (Fiberon PET-GF15)[3]
Brittleness1–5Brittle — snaps with little warning[4]Brittle — snaps with little warning; elongation 4.0 % in XY and 2.6 % in Z[3]
Hardness (scale-specific)Shore A / Shore D / Rockwell77 Shore D (Prusa Polymers method)[2]Not documented
Creep resistance / sustained load1–5Below average — a 12 mm bar sagged to 16.4 mm over 5 days at 1.25 kg, less than plain PETG's 19.4[17]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[22][23][17]
Fatigue / repeated-flex resistance1–5Moderate — no CF-grade S-N curve; unfilled printed PETG ran 79 000–193 000 cycles at 30 % of tensile strength[24]Below average — no GF-grade S-N curve; elongation at break falls to 4.0 % in XY against 5.2–9.3 % unfilled[3][24]
Elasticity / flexibility1–5Rigid[1]Rigid[3]
Z strength as % of XY%83 (Bambu Lab, printed Z against XY tensile)[1]80 (Fiberon PET-GF15, printed Z against XY tensile)[3]
Thermal Properties
HDT at 0.45 MPa°C74 (Bambu Lab) and 96 (Prusament), 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°C68 (Bambu Lab) and 80 (Prusament), 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)°C68 (Bambu Lab) and 80 (3DXTech), DSC[1][4]59.5 (DSC)[3]
Melting point / Vicat°C225 melting (Bambu Lab, DSC) — the carbon fibre lets the PET fraction crystallise[1]231.6 melting (DSC); Vicat 232.6 (ISO 306)[3]
Continuous service temperature°C77 — loaded bars begin to move at this temperature, against 61 for Bambu Lab PETG Basic[17]Not documented
Annealing responseNot documentedAnnealing 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)[25]
Flammability / UL 94Flammable; no UL 94 rating published[1]UL 94 HB at 1.5 mm (Fiberon PET-GF15)[3]
Environment & Chemical
UV resistance1–5Moderate — a season or two; the carbon fibre does not add UV stabilisation[16]Not documented
Chemical resistanceWithstands acids, alkalis, oils and UV exposure, as for unfilled PETG[16]Withstands acids, alkalis, oils and UV exposure[16]
Food contactNot certified for food contact[16]Not certified for food contact as filament[16]
Biodegradability / compostabilityNot biodegradable[16]Not biodegradable[16]
RecyclabilityFibre-filled PETG is not accepted in household plastic collection[16]Not accepted in household plastic collection[16]
Electrical & ESD propertiesSurface resistance above 10⁹ ohm/sq — carbon fibre at this loading is not static-dissipative (3DXTech)[4]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[26]Moderate — measurable VOCs and UFPs, ventilation advised[26]
Ventilation / filtration requirement1–5Open a window / occasional ventilation[26]Open a window / occasional ventilation[26]
Dust & fibre handling hazardCarbon fibre is bound in the matrix; sanding dust should not be inhaled[4]Glass fibre is bound in the matrix; avoid inhaling sanding dust[3]
Post-Processing
Sanding & machiningSands to a matte finish more readily than unfilled PETG[18]Sands poorly — the material is tough and gums rather than powders[18]
Gluing & solvent weldingCyanoacrylate; no common solvent welds it[18]Cyanoacrylate; no common solvent welds PETG cleanly[18]
Vapour / chemical smoothingNo practical vapour smoothing[18]No practical vapour smoothing[18]
Support material pairingSupport for PLA or its own material (Bambu Lab)[1]Prints its own supports; Polymaker rates PolyDissolve S1 for PETG[18]
Dimensional accuracy & detailMatte finish hides layer lines; stringing is reduced against unfilled PETG[1]Not documented
Solvents & Solubility
Soluble inNo common workshop solvent; dichloromethane — a carcinogen — dissolves the matrix surface, 1,2-dichloroethane destroys it in a week.[27][28]No common workshop solvent; dichloromethane — a carcinogen — dissolves the matrix surface, 1,2-dichloroethane destroys it in a week.[27][28]
Softened or crazed byAcetone (+16 % weight over 1 year at 23 °C), ethyl acetate, toluene and DMF swell and soften it; methanol crazes it.[27]Acetone (+16 % weight over 1 year at 23 °C), ethyl acetate, toluene and DMF swell and soften it; methanol crazes it.[27]
Solvent welding & smoothing agentDichloromethane reaches only the resin, so the fibre is left standing proud of the surface. Controlled carcinogen.[28]Dichloromethane reaches only the resin, so the fibre is left standing proud of the surface. Controlled carcinogen.[28]

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 — PETG-CF Bambu Lab · 2026-08 · tds
  2. Prusament PETG Carbon Fiber Technical Datasheet Prusa Polymers · 2026-08 · tds
  3. Fiberon PET-GF15 Technical Data Sheet V1.0 Polymaker · 2026-08 · tds
  4. CarbonX Carbon Fiber PETG Technical Data Sheet 3DXTech · 2026-08 · tds
  5. Printed Solid product catalogue Printed Solid · 2026-08 · vendor
  6. SUNLU PETG-CF (PETG Carbon Fiber) 3D Printer Filament 1 kg SUNLU · 2026-08 · vendor
  7. Fibreheart PETG-CF Pro Filament product page Siraya Tech · 2026-08 · vendor
  8. IEMAI CF-PETG 3D Printing Filament product page IEMAI 3D · 2026-08 · vendor
  9. Reli3D Carbon Fiber PETG Filament 1.75 mm, 1 kg Reli3D (Amazon US) · 2026-08 · vendor
  10. PET-G CF15 Sakata 3D Filaments · 2026-08 · vendor
  11. Filament PM CFJet technical data sheet (TDS CFJet ENG.pdf) Filament PM (Plasty Mladec) · 2026-08 · tds
  12. ELEGOO product catalogue ELEGOO · 2026-08 · vendor
  13. Polymaker product catalogue Polymaker · 2026-08 · vendor
  14. 3DXTech product catalogue 3DXTech · 2026-08 · vendor
  15. Prusament PETG Technical Datasheet v1.1 Prusa Polymers · 2022-02 · tds
  16. PETG — material basics Polymaker Wiki · 2026-08 · doc
  17. BambuLab PETG Basic vs Translucent vs PETG-CF — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  18. PET and PETG — Ultimate 3D Printing Materials Guide Simplify3D · 2026-08 · doc
  19. CARBONX PETG+CF — product page (print recommendations) 3DXTech · 2026-08 · doc
  20. Composite materials filled with carbon, kevlar or glass Prusa Knowledge Base · 2026-08 · doc
  21. Wet Filament — signs, causes and drying Polymaker Wiki · 2026-08 · doc
  22. Extrudr PETG vs PCTG vs XPETG-CF — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  23. Prusament PETG-CF vs PETG V0 vs PETG — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  24. Mechanical Properties of Additively Manufactured Polymeric Materials — PLA and PETG — For Biomechanical Applications Polymers 16(13):1868 · 2024-06 · paper
  25. 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
  26. 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
  27. Eastman Spectar copolyester — Chemical resistance (unstressed bars, 1 year at 23 °C) Eastman Chemical Company · 2026-08 · tds
  28. Improve your 3D prints with chemical smoothing Prusa Research · 2026-08 · doc