3D Printing Info

Filament comparison

PETG vs PETG-GF

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

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

2 selected · all documented properties

Open these two in the interactive comparisonMore PETG comparisonsMore PETG-GF comparisons
PETG vs PETG-GF — documented properties and sources
PropertyPETGPETGGlass-fibre polyester (PETG-GF / PET-GF)PETG
Market snapshot
Listing priceUSD/kg; dated snapshots$19.99/kg median; $8.99–$69.99/kg across 21 dated product listings$27.38/kg median; $18.99–$29.99/kg across 3 dated product listings
Identity & Market
Base polymer / chemistryPolyethylene terephthalate glycol copolymer — PET with a glycol comonomer that suppresses crystallisation[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/cm³1.24–1.30 (ISO 1183)[1][2][4][5]1.43 (Fiberon PET-GF15, ISO 1183)[3]
Typical priceUSD/kg1 kg spools cluster near 20[6][7][8]1 kg spools cluster near 25[9][7]
Price range across brandsUSD/kg12–70 across brands; IEMAI 12, ELEGOO 14, CHCKX 14, Bambu Lab 18–20, Hatchbox 26, Prusament 38, Prusament PETG V0 70[6][7][10][8][11][12]19–30 across brands; ELEGOO 19, Polymaker Fiberon 30[9][7]
Market availability1–5Ubiquitous, every brand and retailer[6][7][9][8]Niche, a handful of specialist brands[9][7]
Spool sizes & diameters1.75 and 2.85 mm; 0.75, 0.8 and 1 kg spools plus spool-less refills[7][8]1.75 mm; 0.5 and 1 kg spools[7]
Typical applicationsFunctional parts, enclosures and outdoor fittings that need more toughness and heat tolerance than PLA[1][2]Stiff, dimensionally stable fixtures; the Fiberon grade is designed to be annealed for heat resistance[3]
Diameter tolerance± mm±0.02 (Prusament)[1]Not documented
Printing Parameters
Nozzle temperature°C230–260 across brands; Prusament 250 ± 10, Polymaker 240–260[1][2][5]Not documented
Bed temperature°C60–90; Prusament 80 ± 10, Polymaker 60–70[1][5]Not documented
Enclosure / chamber requirement1–5Open frame is fine[5]Not documented
Part cooling fanAround 50 %; Polymaker specifies 20–60 %, less than PLA to protect layer bonding[1][5]Not documented
Bed surface & adhesion aidTextured PEI, satin or powder-coated sheets. On smooth PEI a glue stick is used as a release agent, not an adhesive — PETG bonds to bare PEI hard enough to tear the sheet[1][5]Textured PEI, satin or powder-coated sheets; on smooth PEI a glue stick acts as a release agent[1][13]
Maximum volumetric flow (mm³/s; see test conditions)mm³/s8–15 (PrusaSlicer guidance); My Tech Fun ran Bambu Lab PETG Basic at 13 mm³/s[14][15]Not documented
Warping tendency1–5Slight — corner lift on large flat parts[1][5]Not documented
Bed-adhesion difficulty1–5Needs the right surface or a thin adhesive — the problem is releasing the part, not sticking it[1]Needs the right surface or a thin adhesive — the problem is releasing the part, not sticking it[1][13]
Stringing / oozing tendency1–5Moderate — retraction tuning needed[1][5]Moderate — retraction tuning needed; Polymaker names stringing as PETG's common quirk[13]
Overall printing difficulty1–5Easy — minor profile tuning[5]Not documented
Hardware Wear & Reliability
Nozzle hardness required1–4Brass fine indefinitely[14]Hardened steel required[3]
Abrasiveness1–5Non-abrasive[5]Highly abrasive — standard GF composite[3]
Nozzle clog risk1–5Low — no special hot-end required and clogging is not among the listed drawbacks; Prusa lists no drybox and no hardened nozzle[16][17]Moderate — needs dry filament and a clean nozzle; Prusa lists higher risk of nozzle clogging for glass-filled composites[18]
Heat-creep / jam sensitivity1–5Slightly sensitive[16]Slightly sensitive[16]
Hotend requirementNo special hot-end required[16]No special hot-end required[16]
Moisture Behaviour
Moisture absorption (hygroscopicity)1–5Moderate (0.3–0.8 %) — Bambu Lab reports 0.40 % saturated at 25 °C / 55 % RH; Prusa measures only 0.07 % in 24 h and 0.10 % in 7 days at the drier 22 % RH[1][19]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[1]
Equilibrium moisture content at ~50 % RH%0.10 after 7 days at 24 °C / 22 % RH (Prusa Polymers); 0.40 saturated at 25 °C / 55 % RH (Bambu Lab)[1][19]Not documented
Drying temperature & time60–65 °C for 6–8 h[5][19]Not documented
Symptoms when wetBubbling and popping at the nozzle, stringing and a rough surface[1]Bubbling and popping at the nozzle, stringing and a rough surface[20]
Effect of moisture on strengthPolymaker groups PETG with nylon, PVA and TPU as highly hygroscopic and shows a before-and-after-drying comparison; the loss appears as poor layer adhesion and weak, brittle layers rather than a published dry-versus-conditioned figure[20]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[20]
Storage requirementSealed with desiccant; Polymaker groups PETG with the highly hygroscopic materials[20][13]Sealed with desiccant; Polymaker groups PETG with the highly hygroscopic materials[20][13]
Mechanical Properties
Tensile strength (XY)MPa38–51 (printed XY, ISO 527); Prusament 47 ± 2 at yield; 62 on My Tech Fun 4×4 mm bars[1][2][4][21]59.9 ± 0.8 printed XY, ISO 527 (Fiberon PET-GF15)[3]
Young's modulusMPa1500–2311 (printed XY, ISO 527)[1][2][4][5]4144 ± 133 printed XY, ISO 527 (Fiberon PET-GF15)[3]
Elongation at break%5.2–9.3 at break (printed XY, ISO 527); Prusament 5.1 at yield[2][4][5][1]4.0 ± 0.5 printed XY, ISO 527 (Fiberon PET-GF15)[3]
Flexural strengthMPa58–80 (printed XY, ISO 178); Prusament 66 ± 2[1][2][4][5]104.2 ± 2.4 printed XY, ISO 178 (Fiberon PET-GF15)[3]
Flexural modulusMPa1068–2277 (printed XY, ISO 178)[1][2][4][5]3705 ± 85 printed XY, ISO 178 (Fiberon PET-GF15)[3]
Charpy impact, notchedkJ/m²2.6 (PolyLite) to 11.6 (PolyMax) printed XY, ISO 179, notched; Prusament 6 ± 1[2][4][1]8.7 ± 0.6 printed XY, ISO 179, notched (Fiberon PET-GF15)[3]
Other impact dataCharpy unnotched does not break on Prusa's 4 J pendulum (ISO 179-1); Izod 3.37 kJ/m² on My Tech Fun printed bars[1][21]Charpy unnotched 27.2 ± 2.0 printed XY (Fiberon PET-GF15, ISO 179)[3]
Layer adhesion / Z tensileMPa18 ± 4 (Prusa interlayer adhesion test); 42.8 printed Z for PolyLite PETG; 33 on My Tech Fun bars[1][2][21]48.2 ± 0.3 printed Z, ISO 527 (Fiberon PET-GF15)[3]
Brittleness1–5Moderate[1][2]Brittle — snaps with little warning; elongation 4.0 % in XY and 2.6 % in Z[3]
Hardness (scale-specific)Shore A / Shore D / Rockwell74 Shore D (Prusa Polymers method); measured on printed bars at 68.2 for Extrudr PETG, 72 for Fiberlogy PETG and 72.8 for Prusament PETG[1][21][22][23]Not documented
Creep resistance / sustained load1–5Below average — a 12 mm bar sagged to 18.2 mm (Fiberlogy) and 19.4 mm (Bambu Lab Basic) over 5 days at 1.25 kg[21][15]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][15]
Fatigue / repeated-flex resistance1–5Moderate — 79 000–193 000 cycles at 30 % of tensile strength, about three times printed PLA (R = 0.2, 7 Hz)[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 / flexibility1–5Slightly flexible in thin sections[1]Rigid[3]
Z strength as % of XY%84 (PolyLite, printed Z against XY tensile)[2]80 (Fiberon PET-GF15, printed Z against XY tensile)[3]
Thermal Properties
HDT at 0.45 MPa°C68 (Prusament) to 78 (PolyLite), ISO 75 at 0.45 MPa[1][2][5]81.6 as printed, 133.7 after annealing (ISO 75, 0.45 MPa)[3]
HDT at 1.8 MPa°C65 (Polymaker) to 75 (PolyLite), ISO 75 at 1.8 MPa; Prusament 68[1][2][5]71.8 as printed, 87.3 after annealing (ISO 75, 1.8 MPa)[3]
Glass transition (Tg)°C71–81 (DSC)[2][4][5]59.5 (DSC)[3]
Melting point / Vicat°CAmorphous — no melting point; Vicat 75–84 (ISO 306)[2][4][5]231.6 melting (DSC); Vicat 232.6 (ISO 306)[3]
Continuous service temperature°C61–66 — loaded bars begin to move at this temperature across six grades from four brands; Prusa publishes 68 for Prusament PETG[21][22][23][15][25]Not documented
Annealing responseNot documentedAnnealing lifts HDT at 0.45 MPa from 81.6 to 133.7 °C[3]
Thermal expansion (CTE)µm/m·K65 at 30 °C (neat PETG, large-format printed bead, TMA)[26]20 along the print bead and 63–74 in the build direction at 30 °C (30 wt% GF, large-format printed, TMA)[26]
Flammability / UL 94Flammable; no UL 94 rating published for standard PETG, though flame-retardant V0 grades exist[27][13]UL 94 HB at 1.5 mm (Fiberon PET-GF15)[3]
Environment & Chemical
UV resistance1–5Moderate — a season or two[1]Not documented
Chemical resistanceWithstands acids, alkalis, oils and UV exposure — Polymaker names outdoor use as a result[13]Withstands acids, alkalis, oils and UV exposure[13]
Water / humidity resistance in service1–5Good — minor absorption[1]Not documented
Food contactPET is the polymer of drinks bottles, but printed layer grooves harbour bacteria and no filament here carries a food-contact certification[13]Not certified for food contact as filament[13]
Biodegradability / compostabilityNot biodegradable[13]Not biodegradable[13]
RecyclabilityPET is widely recycled as bottle stock, but printed PETG waste is not accepted in household collection[13]Not accepted in household plastic collection[13]
Electrical & ESD propertiesNot documentedSurface resistivity above 10¹² ohm — insulating (Fiberon PET-GF15, ANSI/ESD S11.11)[3]
Health & Safety
Fume toxicity1–5Moderate — measurable VOCs and UFPs, ventilation advised[28]Moderate — measurable VOCs and UFPs, ventilation advised[28]
Ultrafine-particle emission rateparticles/min≈5 × 10⁹ median for the PET-based T-Glase filament in the same chamber study, against ≈1 × 10⁸ for PLA[28]Not documented
Ventilation / filtration requirement1–5Open a window / occasional ventilation[28]Open a window / occasional ventilation[28]
Dust & fibre handling hazardNot documentedGlass 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[16]Sands poorly — the material is tough and gums rather than powders[16]
Painting & finishingPaint adheres poorly without abrasion and a primer[1]Not documented
Gluing & solvent weldingCyanoacrylate; no common solvent welds PETG cleanly[16]Cyanoacrylate; no common solvent welds PETG cleanly[16]
Vapour / chemical smoothingNo practical vapour smoothing[1]No practical vapour smoothing[16]
Support material pairingPrints its own supports; Polymaker rates PolyDissolve S1 for PETG[16]Prints its own supports; Polymaker rates PolyDissolve S1 for PETG[16]
Dimensional accuracy & detailStringing and blobbing are the usual accuracy limits, not shrinkage[1][5]Not documented
Solvents & Solubility
Soluble inNo common workshop solvent; 1,2-dichloroethane destroys it inside a week and dichloromethane — a carcinogen — dissolves the surface.[29][30]No common workshop solvent; dichloromethane — a carcinogen — dissolves the matrix surface, 1,2-dichloroethane destroys it in a week.[29][30]
Softened or crazed byAcetone (+16 % weight over 1 year at 23 °C), ethyl acetate, toluene and DMF swell and soften it; methanol crazes it.[29]Acetone (+16 % weight over 1 year at 23 °C), ethyl acetate, toluene and DMF swell and soften it; methanol crazes it.[29]
Solvent welding & smoothing agentDichloromethane brushed on is the only agent that smooths PETG — a controlled carcinogen, not workshop stock.[30]Dichloromethane reaches only the resin, so the fibre is left standing proud of the surface. Controlled carcinogen.[30]

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 Technical Datasheet v1.1 Prusa Polymers · 2022-02 · tds
  2. PolyLite PETG Technical Data Sheet Polymaker Wiki · 2026-08 · tds
  3. Fiberon PET-GF15 Technical Data Sheet V1.0 Polymaker · 2026-08 · tds
  4. PolyMax PETG Technical Data Sheet Polymaker Wiki · 2026-08 · tds
  5. Polymaker PETG Technical Data Sheet Polymaker Wiki · 2026-08 · tds
  6. PETG Basic — product page Bambu Lab US Store · 2026-08 · vendor
  7. Polymaker product catalogue Polymaker · 2026-08 · vendor
  8. Printed Solid product catalogue Printed Solid · 2026-08 · vendor
  9. ELEGOO product catalogue ELEGOO · 2026-08 · vendor
  10. Black PETG Filament 1.75 mm 1 kg — product data Hatchbox · 2026-08 · vendor
  11. IEMAI PETG 3D Printing Filament product page IEMAI 3D · 2026-08 · vendor
  12. CHCKX PETG 3D Printer Filament 1.75 mm 1 kg, Black CHCKX (Amazon US) · 2026-08 · vendor
  13. PETG — material basics Polymaker Wiki · 2026-08 · doc
  14. Max volumetric speed Prusa Knowledge Base · 2026-08 · doc
  15. BambuLab PETG Basic vs Translucent vs PETG-CF — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  16. PET and PETG — Ultimate 3D Printing Materials Guide Simplify3D · 2026-08 · doc
  17. Filament Material Guide Prusa Knowledge Base · 2026-08 · doc
  18. Composite materials filled with carbon, kevlar or glass Prusa Knowledge Base · 2026-08 · doc
  19. Bambu Filament Technical Data Sheet — PETG HF Bambu Lab · 2026-08 · tds
  20. Wet Filament — signs, causes and drying Polymaker Wiki · 2026-08 · doc
  21. PCTG vs PETG comparison — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  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. Prusament PETG — material page Prusa Polymers · 2026-08 · doc
  26. 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
  27. Prusament PETG V0 Technical Datasheet Prusa Polymers · 2026-08 · tds
  28. 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
  29. Eastman Spectar copolyester — Chemical resistance (unstressed bars, 1 year at 23 °C) Eastman Chemical Company · 2026-08 · tds
  30. Improve your 3D prints with chemical smoothing Prusa Research · 2026-08 · doc