3D Printing Info

Filament comparison

PA6/66 vs PETG

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

PA66 (Nylon 66) guidePETG guide

2 selected · all documented properties

Open these two in the interactive comparisonMore PA6/66 comparisonsMore PETG comparisons
PA6/66 vs PETG — documented properties and sources
PropertyPA66 (Nylon 66)PAPETGPETG
Market snapshot
Listing priceUSD/kg; dated snapshotsNot documented$19.99/kg median; $8.99–$69.99/kg across 21 dated product listings
Identity & Market
Base polymer / chemistryPolyamide 66, condensed from hexamethylenediamine and adipic acid; melts around 40 °C above PA6[1]Polyethylene terephthalate glycol copolymer — PET with a glycol comonomer that suppresses crystallisation[2][3]
Densityg/cm³1.14 (extruded unfilled PA66 stock)[4]1.24–1.30 (ISO 1183)[2][3][5][6]
Typical priceUSD/kgNot documented1 kg spools cluster near 20[7][8][9]
Price range across brandsUSD/kgNot documented12–70 across brands; IEMAI 12, ELEGOO 14, CHCKX 14, Bambu Lab 18–20, Hatchbox 26, Prusament 38, Prusament PETG V0 70[7][8][10][9][11][12]
Market availability1–5Special order, 1–2 makers worldwide — no unfilled PA66 filament appeared in any catalogue searched, and the 3DXTech nylon range offers PA6, PA12 and a 6/66 copolymer but no straight PA66[13][8]Ubiquitous, every brand and retailer[7][8][14][9]
Spool sizes & diametersNot documented1.75 and 2.85 mm; 0.75, 0.8 and 1 kg spools plus spool-less refills[8][9]
Typical applicationsNot documentedFunctional parts, enclosures and outdoor fittings that need more toughness and heat tolerance than PLA[2][3]
Diameter tolerance± mmNot documented±0.02 (Prusament)[2]
Printing Parameters
Nozzle temperature°CNot documented230–260 across brands; Prusament 250 ± 10, Polymaker 240–260[2][3][6]
Bed temperature°CNot documented60–90; Prusament 80 ± 10, Polymaker 60–70[2][6]
Enclosure / chamber requirement1–5Enclosure required (passive)[1]Open frame is fine[6]
Part cooling fanNot documentedAround 50 %; Polymaker specifies 20–60 %, less than PLA to protect layer bonding[2][6]
Bed surface & adhesion aidNot documentedTextured 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[2][6]
Maximum volumetric flow (mm³/s; see test conditions)mm³/sNot documented8–15 (PrusaSlicer guidance); My Tech Fun ran Bambu Lab PETG Basic at 13 mm³/s[15][16]
Warping tendency1–5Not documentedSlight — corner lift on large flat parts[2][6]
Bed-adhesion difficulty1–5Not documentedNeeds the right surface or a thin adhesive — the problem is releasing the part, not sticking it[2]
Stringing / oozing tendency1–5Not documentedModerate — retraction tuning needed[2][6]
Overall printing difficulty1–5Advanced — enclosure, hardware upgrades, tuning[1]Easy — minor profile tuning[6]
Hardware Wear & Reliability
Nozzle hardness required1–4Not documentedBrass fine indefinitely[15]
Abrasiveness1–5Not documentedNon-abrasive[6]
Nozzle clog risk1–5Very high — frequent jams without careful setup[17][18]Low — no special hot-end required and clogging is not among the listed drawbacks; Prusa lists no drybox and no hardened nozzle[19][20]
Heat-creep / jam sensitivity1–5Not documentedSlightly sensitive[19]
Hotend requirementNot documentedNo special hot-end required[19]
Moisture Behaviour
Moisture absorption (hygroscopicity)1–5Very high (>2 %)[18]Moderate (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[2][21]
Equilibrium moisture content at ~50 % RH%8.5 at saturation on extruded PA66 stock (ASTM D570) — the highest uptake of any polymer in this dataset[4]0.10 after 7 days at 24 °C / 22 % RH (Prusa Polymers); 0.40 saturated at 25 °C / 55 % RH (Bambu Lab)[2][21]
Drying temperature & timeNot documented60–65 °C for 6–8 h[6][21]
Symptoms when wetNot documentedBubbling and popping at the nozzle, stringing and a rough surface[2]
Effect of moisture on strengthMeasured dry against wet on printed specimens at 6.16 % moisture (Polymaker CoPA): tensile 78.0 → 34.3 MPa, Young's modulus 2703 → 724 MPa, flexural strength 109.8 → 22.6 MPa, while notched Charpy rises 6.9 → 27.7 kJ/m² and elongation 12.7 → 13.2 %[22][17]Polymaker 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[18]
Storage requirementNot documentedSealed with desiccant; Polymaker groups PETG with the highly hygroscopic materials[18][23]
Mechanical Properties
Tensile strength (XY)MPa82.7 at yield and 84.8 at break on extruded PA66 stock (ASTM D638; converted from 12,000 and 12,300 psi) — no printed figure exists because no unfilled PA66 filament was found[4]38–51 (printed XY, ISO 527); Prusament 47 ± 2 at yield; 62 on My Tech Fun 4×4 mm bars[2][3][5][24]
Young's modulusMPa2413 on extruded PA66 stock (ASTM D638; converted from 350,000 psi)[4]1500–2311 (printed XY, ISO 527)[2][3][5][6]
Elongation at break%50 at break on extruded PA66 stock (ASTM D638)[4]5.2–9.3 at break (printed XY, ISO 527); Prusament 5.1 at yield[3][5][6][2]
Flexural strengthMPa113.8 on extruded PA66 stock (ASTM D790; converted from 16,500 psi)[4]58–80 (printed XY, ISO 178); Prusament 66 ± 2[2][3][5][6]
Flexural modulusMPa3034 on extruded PA66 stock (ASTM D790; converted from 440,000 psi)[4]1068–2277 (printed XY, ISO 178)[2][3][5][6]
Charpy impact, notchedkJ/m²Not documented2.6 (PolyLite) to 11.6 (PolyMax) printed XY, ISO 179, notched; Prusament 6 ± 1[3][5][2]
Other impact dataIzod 53 J/m on extruded PA66 stock, converted from 1.0 ft-lb/in (ASTM D256)[4]Charpy unnotched does not break on Prusa's 4 J pendulum (ISO 179-1); Izod 3.37 kJ/m² on My Tech Fun printed bars[2][24]
Layer adhesion / Z tensileMPaNot documented18 ± 4 (Prusa interlayer adhesion test); 42.8 printed Z for PolyLite PETG; 33 on My Tech Fun bars[2][3][24]
Brittleness1–5Not documentedModerate[2][3]
Hardness (scale-specific)Shore A / Shore D / RockwellShore D 86 and Rockwell 85 (108) — the source does not name the scales on extruded PA66 stock (ASTM D2240, D785)[4]74 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[2][24][25][26]
Creep resistance / sustained load1–5Not documentedBelow 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[24][16]
Fatigue / repeated-flex resistance1–5Excellent — living hinges viable[1]Moderate — 79 000–193 000 cycles at 30 % of tensile strength, about three times printed PLA (R = 0.2, 7 Hz)[27]
Elasticity / flexibility1–5Semi-flexible[17]Slightly flexible in thin sections[2]
Z strength as % of XY%Not documented84 (PolyLite, printed Z against XY tensile)[3]
Wear resistance & frictionWear factor 200e-10 in3*min/(ft*lb*h) on extruded PA66 stock (ASTM D3702); Ensinger lists very good slide and wear properties[4]Not documented
Thermal Properties
HDT at 0.45 MPa°C232 on extruded PA66 stock (ASTM D648 at 66 psi; converted from 450 °F)[4]68 (Prusament) to 78 (PolyLite), ISO 75 at 0.45 MPa[2][3][6]
HDT at 1.8 MPa°C90 on extruded PA66 stock (ASTM D648 at 264 psi; converted from 194 °F) — the gap to the 0.45 MPa figure is the widest in the dataset[4]65 (Polymaker) to 75 (PolyLite), ISO 75 at 1.8 MPa; Prusament 68[2][3][6]
Glass transition (Tg)°CNot documented71–81 (DSC)[3][5][6]
Melting point / Vicat°C255 melting on extruded PA66 stock (ASTM D2133; converted from 491 °F)[4]Amorphous — no melting point; Vicat 75–84 (ISO 306)[3][5][6]
Continuous service temperature°C85 long term and 149 short term on extruded PA66 stock (converted from 185 °F and 300 °F)[4]61–66 — loaded bars begin to move at this temperature across six grades from four brands; Prusa publishes 68 for Prusament PETG[24][25][26][16][28]
Thermal expansion (CTE)µm/m·K81.0 (extruded PA66 stock, ASTM D696; source states 4.5e-5 in/in/°F)[4]65 at 30 °C (neat PETG, large-format printed bead, TMA)[29]
Flammability / UL 94UL 94 V-2 on extruded PA66 stock[4]Flammable; no UL 94 rating published for standard PETG, though flame-retardant V0 grades exist[30][23]
Environment & Chemical
UV resistance1–5Not documentedModerate — a season or two[2]
Chemical resistanceNot documentedWithstands acids, alkalis, oils and UV exposure — Polymaker names outdoor use as a result[23]
Water / humidity resistance in service1–5Not documentedGood — minor absorption[2]
Food contactNot documentedPET is the polymer of drinks bottles, but printed layer grooves harbour bacteria and no filament here carries a food-contact certification[23]
Biodegradability / compostabilityNot documentedNot biodegradable[23]
RecyclabilityNot documentedPET is widely recycled as bottle stock, but printed PETG waste is not accepted in household collection[23]
Electrical & ESD propertiesVolume resistance 1e15 ohm-cm and dielectric constant 4 on extruded PA66 stock (ASTM D257, D150)[4]Not documented
Health & Safety
Fume toxicity1–5Moderate — measurable VOCs and UFPs, ventilation advised[31]Moderate — measurable VOCs and UFPs, ventilation advised[31]
VOC emission rateµg/minUp to 180 caprolactam, the dominant VOC from nylon; total VOC reached nearly 200 µg/min, the highest of the nine filaments tested[31]Not documented
Ultrafine-particle emission rateparticles/min≈2 × 10⁸ median — low for ultrafine particles despite the highest VOC mass of any filament tested[31]≈5 × 10⁹ median for the PET-based T-Glase filament in the same chamber study, against ≈1 × 10⁸ for PLA[31]
Hazardous species emittedCaprolactam, at up to 180 µg/min from nylon filament — the largest single-VOC emission rate measured in the study[31]Not documented
Ventilation / filtration requirement1–5Ventilated room or enclosure recommended[31]Open a window / occasional ventilation[31]
Post-Processing
Sanding & machiningNot documentedSands poorly — the material is tough and gums rather than powders[19]
Painting & finishingNot documentedPaint adheres poorly without abrasion and a primer[2]
Gluing & solvent weldingNot documentedCyanoacrylate; no common solvent welds PETG cleanly[19]
Vapour / chemical smoothingNot documentedNo practical vapour smoothing[2]
Support material pairingNot documentedPrints its own supports; Polymaker rates PolyDissolve S1 for PETG[19]
Dimensional accuracy & detailNot documentedStringing and blobbing are the usual accuracy limits, not shrinkage[2][6]
Solvents & Solubility
Soluble inDissolved at 23 °C by formic acid above ~80 %, phenol, m-cresol, 96 % sulphuric acid or hexafluoroisopropanol — laboratory reagents.[32]No common workshop solvent; 1,2-dichloroethane destroys it inside a week and dichloromethane — a carcinogen — dissolves the surface.[33][34]
Softened or crazed byZinc chloride solutions stress-crack it — 10 % marginal, 37 % not resistant; alcoholic calcium chloride dissolves it.[32]Acetone (+16 % weight over 1 year at 23 °C), ethyl acetate, toluene and DMF swell and soften it; methanol crazes it.[33]
Solvent welding & smoothing agentNone — nylon's only solvents are formic acid, phenol and HFIP, all of which degrade the part they wet.[32]Dichloromethane brushed on is the only agent that smooths PETG — a controlled carcinogen, not workshop stock.[34]

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. PA (Nylon) — material basics Polymaker Wiki · 2026-08 · doc
  2. Prusament PETG Technical Datasheet v1.1 Prusa Polymers · 2022-02 · tds
  3. PolyLite PETG Technical Data Sheet Polymaker Wiki · 2026-08 · tds
  4. TECAMID 66 natural (PA66) — stock shape properties Ensinger · 2026-08 · tds
  5. PolyMax PETG Technical Data Sheet Polymaker Wiki · 2026-08 · tds
  6. Polymaker PETG Technical Data Sheet Polymaker Wiki · 2026-08 · tds
  7. PETG Basic — product page Bambu Lab US Store · 2026-08 · vendor
  8. Polymaker product catalogue Polymaker · 2026-08 · vendor
  9. Printed Solid product catalogue Printed Solid · 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. 3DXTech product catalogue 3DXTech · 2026-08 · vendor
  14. ELEGOO product catalogue ELEGOO · 2026-08 · vendor
  15. Max volumetric speed Prusa Knowledge Base · 2026-08 · doc
  16. BambuLab PETG Basic vs Translucent vs PETG-CF — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  17. Moisture Conditioning — effect on printed nylon properties Polymaker Wiki · 2026-08 · doc
  18. Wet Filament — signs, causes and drying Polymaker Wiki · 2026-08 · doc
  19. PET and PETG — Ultimate 3D Printing Materials Guide Simplify3D · 2026-08 · doc
  20. Filament Material Guide Prusa Knowledge Base · 2026-08 · doc
  21. Bambu Filament Technical Data Sheet — PETG HF Bambu Lab · 2026-08 · tds
  22. PolyMide CoPA Technical Data Sheet V5.4 (dry and wet status blocks) Polymaker · 2024-11 · tds
  23. PETG — material basics Polymaker Wiki · 2026-08 · doc
  24. PCTG vs PETG comparison — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  25. Extrudr PETG vs PCTG vs XPETG-CF — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  26. Prusament PETG-CF vs PETG V0 vs PETG — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  27. Mechanical Properties of Additively Manufactured Polymeric Materials — PLA and PETG — For Biomechanical Applications Polymers 16(13):1868 · 2024-06 · paper
  28. Prusament PETG — material page Prusa Polymers · 2026-08 · doc
  29. 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
  30. Prusament PETG V0 Technical Datasheet Prusa Polymers · 2026-08 · tds
  31. 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
  32. Ultramid Nylon Chemical Resistance guide (unmodified PA6 B27E and PA66 A27E) BASF · 2026-08 · tds
  33. Eastman Spectar copolyester — Chemical resistance (unstressed bars, 1 year at 23 °C) Eastman Chemical Company · 2026-08 · tds
  34. Improve your 3D prints with chemical smoothing Prusa Research · 2026-08 · doc