3D Printing Info

Filament comparison

PETG-GF vs PSU

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

Glass-fibre polyester (PETG-GF / PET-GF) guidePSU guide

2 selected · all documented properties

Open these two in the interactive comparisonMore PETG-GF comparisonsMore PSU comparisons
PETG-GF vs PSU — documented properties and sources
PropertyGlass-fibre polyester (PETG-GF / PET-GF)PETGPSUHIGHTEMP
Market snapshot
Listing priceUSD/kg; dated snapshots$27.38/kg median; $18.99–$29.99/kg across 3 dated product listings$168.00/kg median; $168.00–$168.00/kg across 1 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]Polysulfone — the lowest-temperature and cheapest of the sulfone family[2]
Densityg/cm³1.43 (Fiberon PET-GF15, ISO 1183)[1]1.24 (ISO 1183)[2]
Typical priceUSD/kg1 kg spools cluster near 25[3][4]1 kg-equivalent spools cluster near 250[5]
Price range across brandsUSD/kg19–30 across brands; ELEGOO 19, Polymaker Fiberon 30[3][4]168-250 across formats; 250 g spool $42 (168/kg), 500 g $125 (250/kg) — 3DXTech is the only filament supplier found[5]
Market availability1–5Niche, a handful of specialist brands[3][4]Special order, 1–2 makers worldwide[5]
Spool sizes & diameters1.75 mm; 0.5 and 1 kg spools[4]1.75 mm; 250 g and 500 g spools[5]
Typical applicationsStiff, dimensionally stable fixtures; the Fiberon grade is designed to be annealed for heat resistance[1]Transparent high-temperature housings, medical trays and hot-water fittings[2]
Printing Parameters
Bed temperature°CNot documented120–140 (3DXTech)[2]
Enclosure / chamber requirement1–5Not documentedActively heated chamber required[6][7]
Bed surface & adhesion aidTextured PEI, satin or powder-coated sheets; on smooth PEI a glue stick acts as a release agent[8][9]Not documented
Bed-adhesion difficulty1–5Needs the right surface or a thin adhesive — the problem is releasing the part, not sticking it[8][9]Not documented
Stringing / oozing tendency1–5Moderate — retraction tuning needed; Polymaker names stringing as PETG's common quirk[9]Not documented
Overall printing difficulty1–5Not documentedExpert / industrial hardware only[6][7]
Hardware Wear & Reliability
Nozzle hardness required1–4Hardened steel required[1]Brass fine indefinitely for unfilled grades, but brass softens near these nozzle temperatures — hardened or plated hot ends are the norm[6]
Abrasiveness1–5Highly abrasive — standard GF composite[1]Non-abrasive when unfilled[2]
Nozzle clog risk1–5Moderate — needs dry filament and a clean nozzle; Prusa lists higher risk of nozzle clogging for glass-filled composites[10]Moderate — needs dry filament and a clean nozzle; 3DXTech lists no special nozzle concerns but a mandatory 120 °C pre-dry before every print[11]
Heat-creep / jam sensitivity1–5Slightly sensitive[12]Not documented
Hotend requirementNo special hot-end required[12]Not documented
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[8]Not documented
Equilibrium moisture content at ~50 % RH%Not documented0.30 in 24 h on extruded stock (ASTM D570)[13]
Symptoms when wetBubbling and popping at the nozzle, stringing and a rough surface[14]Not documented
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[14]No dry-versus-conditioned figures are published; 3DXTech mandates a 120 °C, 4 h pre-dry before every print because trapped water flashes to steam at these nozzle temperatures[11]
Storage requirementSealed with desiccant; Polymaker groups PETG with the highly hygroscopic materials[14][9]Not documented
Mechanical Properties
Tensile strength (XY)MPa59.9 ± 0.8 printed XY, ISO 527 (Fiberon PET-GF15)[1]52 (printed XY, ISO 527, 3DXTech); 81 at break on extruded stock (ASTM D638)[2][13]
Young's modulusMPa4144 ± 133 printed XY, ISO 527 (Fiberon PET-GF15)[1]2100 (printed XY, ISO 527)[2]
Elongation at break%4.0 ± 0.5 printed XY, ISO 527 (Fiberon PET-GF15)[1]8 (printed XY, ISO 527) against 50 on extruded stock — nearly three times PPSU's printed 3 %[2][15][13]
Flexural strengthMPa104.2 ± 2.4 printed XY, ISO 178 (Fiberon PET-GF15)[1]87 (printed XY, ISO 178)[2]
Flexural modulusMPa3705 ± 85 printed XY, ISO 178 (Fiberon PET-GF15)[1]2050 (printed XY, ISO 178)[2]
Charpy impact, notchedkJ/m²8.7 ± 0.6 printed XY, ISO 179, notched (Fiberon PET-GF15)[1]Not documented
Other impact dataCharpy unnotched 27.2 ± 2.0 printed XY (Fiberon PET-GF15, ISO 179)[1]Izod notched 69 J/m on extruded PSU stock, converted from 1.3 ft-lb/in (ASTM D256)[13]
Layer adhesion / Z tensileMPa48.2 ± 0.3 printed Z, ISO 527 (Fiberon PET-GF15)[1]Not documented
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 documentedRockwell M120 on extruded PSU stock (ASTM D785)[13]
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]Good. Ensinger lists high creep resistance as a headline property of extruded PSU stock, which is rated to 173 °C heat deflection at 1.8 MPa[13]
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][19]Not documented
Elasticity / flexibility1–5Rigid[1]Rigid[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]172 (printed XY, ISO 75 at 0.45 MPa, 3DXTech); 181 on extruded stock, converted from 358 °F at 66 psi[2][13]
HDT at 1.8 MPa°C71.8 as printed, 87.3 after annealing (ISO 75, 1.8 MPa)[1]174 on extruded PSU stock, converted from 345 °F at 264 psi (ASTM D648)[13]
Glass transition (Tg)°C59.5 (DSC)[1]187 (DSC, 3DXTech) and 185 on extruded stock (ASTM D3418), against 230 for PPSU[2][15][13]
Melting point / Vicat°C231.6 melting (DSC); Vicat 232.6 (ISO 306)[1]Not documented
Continuous service temperature°CNot documented141 long-term service on extruded PSU stock, converted from 285 °F[13]
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)[20]55.8 (extruded PSU stock, ASTM D696; source states 3.1e-5 in/in/°F)[13]
Flammability / UL 94UL 94 HB at 1.5 mm (Fiberon PET-GF15)[1]UL 94 V-0 on extruded PSU stock[13]
Environment & Chemical
Chemical resistanceWithstands acids, alkalis, oils and UV exposure[9]Not documented
Food contactNot certified for food contact as filament[9]Not documented
Biodegradability / compostabilityNot biodegradable[9]Not documented
RecyclabilityNot accepted in household plastic collection[9]Not documented
Electrical & ESD propertiesSurface resistivity above 10¹² ohm — insulating (Fiberon PET-GF15, ANSI/ESD S11.11)[1]Surface resistance above 10¹³ ohm/sq — an insulator (IEC 60093)[2]
Health & Safety
Fume toxicity1–5Moderate — measurable VOCs and UFPs, ventilation advised[21]Moderate — measurable VOCs and UFPs, ventilation advised. None of these polymers was in the chamber study, and all are processed far above the temperatures it covered[21]
Ventilation / filtration requirement1–5Open a window / occasional ventilation[21]Ventilated room or enclosure recommended[21]
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[12]Not documented
Gluing & solvent weldingCyanoacrylate; no common solvent welds PETG cleanly[12]Not documented
Vapour / chemical smoothingNo practical vapour smoothing[12]Not documented
Support material pairingPrints its own supports; Polymaker rates PolyDissolve S1 for PETG[12]Not documented
Solvents & Solubility
Soluble inNo common workshop solvent; dichloromethane — a carcinogen — dissolves the matrix surface, 1,2-dichloroethane destroys it in a week.[22][23]Chlorinated hydrocarbons — dichloromethane, chloroform — dissolve polysulfone; ketones and esters attack it as well.[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.[22]Acetone, MEK, ethyl acetate, benzene and toluene craze or stress-crack it; methanol and isopropanol only marginally.[25][24]
Solvent welding & smoothing agentDichloromethane reaches only the resin, so the fibre is left standing proud of the surface. Controlled carcinogen.[23]Dichloromethane cement welds PSU and NMP softens residual resin. Both are laboratory reagents.[24]

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. ThermaX PSU Technical Data Sheet v3 3DXTech · 2026-08 · tds
  3. ELEGOO product catalogue ELEGOO · 2026-08 · vendor
  4. Polymaker product catalogue Polymaker · 2026-08 · vendor
  5. 3DXTech product catalogue 3DXTech · 2026-08 · vendor
  6. Prusament PEI 1010 Technical Datasheet v1.0 Prusa Polymers · 2024-09 · tds
  7. Prusament PEI 1010 — material page Prusa Polymers · 2026-08 · doc
  8. Prusament PETG Technical Datasheet v1.1 Prusa Polymers · 2022-02 · tds
  9. PETG — material basics Polymaker Wiki · 2026-08 · doc
  10. Composite materials filled with carbon, kevlar or glass Prusa Knowledge Base · 2026-08 · doc
  11. THERMAX PSU — product page (print recommendations) 3DXTech · 2026-08 · doc
  12. PET and PETG — Ultimate 3D Printing Materials Guide Simplify3D · 2026-08 · doc
  13. TECASON S natural (PSU) — stock shape properties Ensinger · 2026-08 · tds
  14. Wet Filament — signs, causes and drying Polymaker Wiki · 2026-08 · doc
  15. ThermaX PPSU Technical Data Sheet v3 3DXTech · 2026-08 · tds
  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. Mechanical Properties of Additively Manufactured Polymeric Materials — PLA and PETG — For Biomechanical Applications Polymers 16(13):1868 · 2024-06 · paper
  20. 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
  21. 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
  22. Eastman Spectar copolyester — Chemical resistance (unstressed bars, 1 year at 23 °C) Eastman Chemical Company · 2026-08 · tds
  23. Improve your 3D prints with chemical smoothing Prusa Research · 2026-08 · doc
  24. Radel PPSU, Veradel PESU, Acudel modified PPSU Design Guide — environmental stress cracking tables Solvay Specialty Polymers · 2026-08 · tds
  25. Chemical resistance — resistance of Ensinger plastics to chemicals (DIN 50 014, 23/50) Ensinger · 2026-08 · tds