3D Printing Info

Filament comparison

PETG-GF vs rPETG

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

Glass-fibre polyester (PETG-GF / PET-GF) guideRecycled PETG (rPETG) guide

2 selected · all documented properties

Open these two in the interactive comparisonMore PETG-GF comparisonsMore rPETG comparisons
PETG-GF vs rPETG — documented properties and sources
PropertyGlass-fibre polyester (PETG-GF / PET-GF)PETGRecycled PETG (rPETG)PETG
Market snapshot
Listing priceUSD/kg; dated snapshots$27.38/kg median; $18.99–$29.99/kg across 3 dated product listings$28.99/kg median; $17.24–$39.98/kg across 4 dated product listings
Identity & Market
Base polymer / chemistryGlass-fibre reinforced polyester. Polymaker's Fiberon PET-GF15 uses a PET rather than a PETG matrix and carries 15 wt% glass fibre[1]PETG regranulated from recycled polyester waste; Polymaker's Fiberon PETG-rCF08 adds 8 wt% recycled carbon fibre[2][3][4]
Densityg/cm³1.43 (Fiberon PET-GF15, ISO 1183)[1]1.27 (Prusament) and 1.30 (Fiberon PETG-rCF08), ISO 1183[2][4]
Typical priceUSD/kg1 kg spools cluster near 25[5][6]1 kg spools cluster near 29[7][8][6][9]
Price range across brandsUSD/kg19–30 across brands; ELEGOO 19, Polymaker Fiberon 30[5][6]17–40 across brands; Filament PM RePETG 17, 3DXTech ECOMAX 26, GreenGate3D 32, Fiberon rCF08 40[7][8][6][9]
Market availability1–5Niche, a handful of specialist brands[5][6]Available from several mainstream brands[7][8][6]
Spool sizes & diameters1.75 mm; 0.5 and 1 kg spools[6]1.75 and 2.85 mm; 0.5, 1 and 3 kg spools[6][8]
Typical applicationsStiff, dimensionally stable fixtures; the Fiberon grade is designed to be annealed for heat resistance[1]Not documented
Diameter tolerance± mmNot documented±0.05 (Prusament PETG Recycled), against ±0.02 for virgin Prusament PETG[2][10]
Printing Parameters
Nozzle temperature°CNot documented250 ± 10 (Prusament); 230–255 (Spectrum)[2][3]
Bed temperature°CNot documented80 ± 10 (Prusament); 60–80 (Spectrum)[2][3]
Enclosure / chamber requirement1–5Not documentedOpen frame is fine — Spectrum states a closed chamber is not necessary[3]
Part cooling fanNot documented50 % (Prusament); up to 100 % (Spectrum)[2][3]
Bed surface & adhesion aidTextured PEI, satin or powder-coated sheets; on smooth PEI a glue stick acts as a release agent[10][11]Textured PEI, satin or powder-coated sheets; on smooth PEI a glue stick acts as a release agent[10][11]
Bed-adhesion difficulty1–5Needs the right surface or a thin adhesive — the problem is releasing the part, not sticking it[10][11]Needs the right surface or a thin adhesive — the problem is releasing the part, not sticking it[10][11]
Stringing / oozing tendency1–5Moderate — retraction tuning needed; Polymaker names stringing as PETG's common quirk[11]Moderate — retraction tuning needed; Polymaker names stringing as PETG's common quirk[11]
Overall printing difficulty1–5Not documentedEasy — minor profile tuning; Spectrum describes printing as similar to standard PETG[3]
Hardware Wear & Reliability
Nozzle hardness required1–4Hardened steel required[1]Brass fine indefinitely[2]
Abrasiveness1–5Highly abrasive — standard GF composite[1]Not documented
Nozzle clog risk1–5Moderate — needs dry filament and a clean nozzle; Prusa lists higher risk of nozzle clogging for glass-filled composites[12]Low — recycled PETG prints on the same hardware as virgin PETG: no special hot-end, no drybox and no hardened nozzle[13][14]
Heat-creep / jam sensitivity1–5Slightly sensitive[13]Slightly sensitive[13]
Hotend requirementNo special hot-end required[13]No special hot-end required[13]
Moisture Behaviour
Moisture absorption (hygroscopicity)1–5Moderate (0.3–0.8 %) — the PETG matrix reaches 0.40 % saturated at 25 °C / 55 % RH; no glass-filled grade publishes its own figure[10]Moderate (0.3–0.8 %) — recycled PETG shares the virgin matrix, which reaches 0.40 % saturated at 25 °C / 55 % RH[10]
Equilibrium moisture content at ~50 % RH%Not documented0.07 after 24 h and 0.10 after 7 days at 24 °C / 22 % RH (Prusa Polymers)[2]
Symptoms when wetBubbling and popping at the nozzle, stringing and a rough surface[15]Bubbling and popping at the nozzle, stringing and a rough surface[15]
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[15]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[15]
Storage requirementSealed with desiccant; Polymaker groups PETG with the highly hygroscopic materials[15][11]Sealed with desiccant; Polymaker groups PETG with the highly hygroscopic materials[15][11]
Mechanical Properties
Tensile strength (XY)MPa59.9 ± 0.8 printed XY, ISO 527 (Fiberon PET-GF15)[1]43 ± 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[2][10][3]
Young's modulusMPa4144 ± 133 printed XY, ISO 527 (Fiberon PET-GF15)[1]1500 printed horizontal, 1600 printed vertical (Prusament, ISO 527-1) — the same as virgin Prusament PETG[2][10]
Elongation at break%4.0 ± 0.5 printed XY, ISO 527 (Fiberon PET-GF15)[1]4.5 at yield printed (Prusament); Spectrum quotes 400 at break on moulded specimens[2][3]
Flexural strengthMPa104.2 ± 2.4 printed XY, ISO 178 (Fiberon PET-GF15)[1]63 ± 1 printed horizontal, ISO 178 (Prusament), against 66 ± 2 for virgin Prusament PETG[2][10]
Flexural modulusMPa3705 ± 85 printed XY, ISO 178 (Fiberon PET-GF15)[1]1800 printed horizontal, ISO 178 (Prusament)[2]
Charpy impact, notchedkJ/m²8.7 ± 0.6 printed XY, ISO 179, notched (Fiberon PET-GF15)[1]12 ± 1 printed horizontal and 15 ± 3 printed vertical, ISO 179-1 notched (Prusament)[2]
Other impact dataCharpy unnotched 27.2 ± 2.0 printed XY (Fiberon PET-GF15, ISO 179)[1]Charpy unnotched 25 ± 3 printed horizontal and 38 ± 11 printed vertical (Prusament, ISO 179-1)[2]
Layer adhesion / Z tensileMPa48.2 ± 0.3 printed Z, ISO 527 (Fiberon PET-GF15)[1]15 ± 5 (Prusa Polymers interlayer adhesion test), against 18 ± 4 for virgin Prusament PETG[2][10]
Brittleness1–5Brittle — snaps with little warning; elongation 4.0 % in XY and 2.6 % in Z[1]Moderate[2]
Hardness (scale-specific)Shore A / Shore D / RockwellNot documented74 Shore D (Prusa Polymers method) — the same as virgin Prusament PETG[2][10]
Creep resistance / sustained load1–5Below 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[16][17][18]Below average — no recycled-grade creep test; virgin PETG sagged from 12 to 17.1–20.4 mm over 5 days at 1.25 kg[19][16][17][18]
Fatigue / repeated-flex resistance1–5Below average — no GF-grade S-N curve; elongation at break falls to 4.0 % in XY against 5.2–9.3 % unfilled[1][20]Moderate — no recycled-grade S-N curve; virgin printed PETG ran 79 000–193 000 cycles at 30 % of tensile strength[20]
Elasticity / flexibility1–5Rigid[1]Slightly flexible in thin sections[2]
Z strength as % of XY%80 (Fiberon PET-GF15, printed Z against XY tensile)[1]Not documented
Thermal Properties
HDT at 0.45 MPa°C81.6 as printed, 133.7 after annealing (ISO 75, 0.45 MPa)[1]68 (ISO 75, 0.45 MPa) — the same as virgin Prusament PETG; Spectrum quotes 70[2][10][3]
HDT at 1.8 MPa°C71.8 as printed, 87.3 after annealing (ISO 75, 1.8 MPa)[1]68 (ISO 75, 1.8 MPa)[2]
Glass transition (Tg)°C59.5 (DSC)[1]Not documented
Melting point / Vicat°C231.6 melting (DSC); Vicat 232.6 (ISO 306)[1]Not documented
Annealing responseAnnealing lifts HDT at 0.45 MPa from 81.6 to 133.7 °C[1]Not documented
Thermal expansion (CTE)µm/m·K20 along the print bead and 63–74 in the build direction at 30 °C (30 wt% GF, large-format printed, TMA)[21]Not documented
Flammability / UL 94UL 94 HB at 1.5 mm (Fiberon PET-GF15)[1]Flammable; no UL 94 rating published for standard grades[22]
Environment & Chemical
Chemical resistanceWithstands acids, alkalis, oils and UV exposure[11]Withstands acids, alkalis, oils and UV exposure[11]
Food contactNot certified for food contact as filament[11]Not certified for food contact as filament[11]
Biodegradability / compostabilityNot biodegradable[11]Not biodegradable[11]
RecyclabilityNot accepted in household plastic collection[11]The feedstock itself — Spectrum describes collecting, shredding and re-homogenising PETG waste[3]
Electrical & ESD propertiesSurface resistivity above 10¹² ohm — insulating (Fiberon PET-GF15, ANSI/ESD S11.11)[1]Not documented
Health & Safety
Fume toxicity1–5Moderate — measurable VOCs and UFPs, ventilation advised[23]Moderate — measurable VOCs and UFPs, ventilation advised[23]
Ventilation / filtration requirement1–5Open a window / occasional ventilation[23]Open a window / occasional ventilation[23]
Dust & fibre handling hazardGlass fibre is bound in the matrix; avoid inhaling sanding dust[1]Not documented
Post-Processing
Sanding & machiningSands poorly — the material is tough and gums rather than powders[13]Sands poorly — the material is tough and gums rather than powders[13]
Gluing & solvent weldingCyanoacrylate; no common solvent welds PETG cleanly[13]Cyanoacrylate; no common solvent welds PETG cleanly[13]
Vapour / chemical smoothingNo practical vapour smoothing[13]No practical vapour smoothing[13]
Support material pairingPrints its own supports; Polymaker rates PolyDissolve S1 for PETG[13]Prints its own supports; Polymaker rates PolyDissolve S1 for PETG[13]
Solvents & Solubility
Soluble inNo common workshop solvent; dichloromethane — a carcinogen — dissolves the matrix surface, 1,2-dichloroethane destroys it in a week.[24][25]No common workshop solvent; 1,2-dichloroethane destroys it inside a week and dichloromethane — a carcinogen — dissolves the surface.[24][25]
Softened or crazed byAcetone (+16 % weight over 1 year at 23 °C), ethyl acetate, toluene and DMF swell and soften it; methanol crazes it.[24]Acetone (+16 % weight over 1 year at 23 °C), ethyl acetate, toluene and DMF swell and soften it; methanol crazes it.[24]
Solvent welding & smoothing agentDichloromethane reaches only the resin, so the fibre is left standing proud of the surface. Controlled carcinogen.[25]Dichloromethane brushed on is the only agent that smooths PETG — a controlled carcinogen, not workshop stock.[25]

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. Fiberon PET-GF15 Technical Data Sheet V1.0 Polymaker · 2026-08 · tds
  2. Prusament PETG Recycled Technical Datasheet Prusa Polymers · 2026-08 · tds
  3. Spectrum r-PETG Technical Data Sheet Spectrum Filaments · 2026-08 · tds
  4. Fiberon PETG-rCF08 Technical Data Sheet V1.0 Polymaker · 2026-08 · tds
  5. ELEGOO product catalogue ELEGOO · 2026-08 · vendor
  6. Polymaker product catalogue Polymaker · 2026-08 · vendor
  7. 3DXTech product catalogue 3DXTech · 2026-08 · vendor
  8. GreenGate3D Recycled PET-G — product data GreenGate3D · 2026-08 · vendor
  9. Filament PM RePETG technical data sheet Filament PM (Plasty Mladec) · 2026-08 · tds
  10. Prusament PETG Technical Datasheet v1.1 Prusa Polymers · 2022-02 · tds
  11. PETG — material basics Polymaker Wiki · 2026-08 · doc
  12. Composite materials filled with carbon, kevlar or glass Prusa Knowledge Base · 2026-08 · doc
  13. PET and PETG — Ultimate 3D Printing Materials Guide Simplify3D · 2026-08 · doc
  14. Filament Material Guide Prusa Knowledge Base · 2026-08 · doc
  15. Wet Filament — signs, causes and drying Polymaker Wiki · 2026-08 · doc
  16. Extrudr PETG vs PCTG vs XPETG-CF — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  17. Prusament PETG-CF vs PETG V0 vs PETG — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  18. BambuLab PETG Basic vs Translucent vs PETG-CF — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  19. PCTG vs PETG comparison — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  20. Mechanical Properties of Additively Manufactured Polymeric Materials — PLA and PETG — For Biomechanical Applications Polymers 16(13):1868 · 2024-06 · paper
  21. 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
  22. Prusament PETG V0 Technical Datasheet Prusa Polymers · 2026-08 · tds
  23. 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
  24. Eastman Spectar copolyester — Chemical resistance (unstressed bars, 1 year at 23 °C) Eastman Chemical Company · 2026-08 · tds
  25. Improve your 3D prints with chemical smoothing Prusa Research · 2026-08 · doc