3D Printing Info

Filament comparison

PCTG vs PEEK

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

PCTG guidePEEK guide

2 selected · all documented properties

Open these two in the interactive comparisonMore PCTG comparisonsMore PEEK comparisons
PCTG vs PEEK — documented properties and sources
PropertyPCTGPETGPEEKHIGHTEMP
Market snapshot
Listing priceUSD/kg; dated snapshots$34.99/kg median; $14.00–$50.67/kg across 5 dated product listings$531.87/kg median; $296.14–$770.00/kg across 5 dated product listings
Identity & Market
Base polymer / chemistryPoly(cyclohexylenedimethylene terephthalate) glycol — a copolyester with a higher cyclohexanedimethanol content than PETG[1][2]Polyether ether ketone — a semi-crystalline polyaryletherketone[3]
Densityg/cm³1.23 (Extrudr, ASTM D792; 3DXTech, ISO 1183)[2][4]1.30 (ISO 1183)[3][5]
Typical priceUSD/kg1 kg spools cluster near 34[6][4][7]1 kg-equivalent spools span 296–770; the middle of the market is about 532[8][9][10]
Price range across brandsUSD/kg14–51 across brands; CHCKX 14 in a 10-roll bundle, Push Plastic 30, Proto-pasta 35 at 1 kg, 3DXTech 51[6][4][11]296-770 across brands and spool sizes; 3D4Makers recycled R-PEEK 296 at 750 g, IEMAI 3D 420 at 1 kg, LEHVOSS Luvocom 3F PEEK 9581 532 at 2 kg, 3DXTech ThermaX PEEK 770 at 500 g[8][9][10]
Market availability1–5Available from several mainstream brands[6][4][7][12]Niche, a handful of specialist brands[8][9][5]
Spool sizes & diameters1.75 and 2.85 mm; 0.5, 0.75, 1, 3 and 5 kg spools[6][7][4]1.75 and 2.85 mm; 200 g to 2 kg spools[8][9][5]
Typical applicationsTransparent covers, guards and impact-loaded parts where PETG cracks[1][2]Aerospace brackets, semiconductor handling, sterilisable medical tooling and downhole parts[3]
Printing Parameters
Nozzle temperature°C250–270 (Spectrum, Extrudr)[1][2]380-400 (3DXTech printed-specimen conditions); Victrex quotes a 340-450 melt range for AM 450 FIL[3][5]
Bed temperature°C60–100 (Spectrum)[1]130–140 (3DXTech)[3]
Enclosure / chamber requirement1–5Open frame is fine — Spectrum and Extrudr both say a closed chamber is not necessary, Extrudr adds it helps on larger parts[1][2]Actively heated chamber required[13][14]
Recommended chamber temperature°CNot documentedNot less than 150 for semi-crystalline printing (Victrex AM 450 FIL); bed above 150[5]
Part cooling fanUp to 100 % (Spectrum); 20–50 % (Extrudr)[1][2]Not documented
Bed surface & adhesion aidTextured PEI, satin or powder-coated sheets; on smooth PEI a glue stick acts as a release agent[15][16]Not documented
Maximum volumetric flow (mm³/s; see test conditions)mm³/s1.6–16 at the 20–200 mm/s Extrudr rates the material for, on a 0.4 mm nozzle at 0.2 mm layer[2][17]Not documented
Warping tendency1–5Not documentedSevere — heated chamber needed[13]
Bed-adhesion difficulty1–5Needs the right surface or a thin adhesive — the problem is releasing the part, not sticking it[15][16]Very difficult — special plates or slurry required[13]
Stringing / oozing tendency1–5Moderate — retraction tuning needed; Polymaker names stringing as PETG's common quirk[16]Not documented
Shrinkage%0.2–0.5 (Extrudr, ASTM D955)[2]Not documented
Overall printing difficulty1–5Easy — minor profile tuning[1][2]Expert / industrial hardware only[13][14]
Extruder requirementNot documentedAn all-metal hot end rated above 400 °C and a heated chamber; 3DXTech tests at 0.25 mm layer height on a 0.4 mm nozzle[3][13]
Hardware Wear & Reliability
Nozzle hardness required1–4Brass fine indefinitely — Extrudr explicitly states no hardened nozzle is needed[2]Brass fine indefinitely for unfilled grades, but brass softens near these nozzle temperatures — hardened or plated hot ends are the norm[13]
Abrasiveness1–5Non-abrasive[2]Non-abrasive when unfilled[3]
Nozzle clog risk1–5Low — 3DXTech lists no special nozzle concerns and no minimum layer height for PCTG, only a 65 °C pre-dry[18]Moderate — needs dry filament and a clean nozzle; 3DXTech lists no special nozzle concerns but a mandatory 120 °C pre-dry before every print[19]
Heat-creep / jam sensitivity1–5Slightly sensitive[20]Not documented
Hotend requirementNo special hot-end required[20]Not documented
Moisture Behaviour
Moisture absorption (hygroscopicity)1–5Moderate (0.3–0.8 %) — the copolyester matrix reaches 0.40 % saturated at 25 °C / 55 % RH and 3DXTech specifies a 65 °C, 4 h pre-dry[15][18]Not documented
Equilibrium moisture content at ~50 % RH%Not documented0.45 at saturation, 23 °C (ISO 62); 0.55 at 100 °C[5]
Drying temperature & timeNot documented120 °C for 5 h, target below 0.020 % moisture (Victrex AM 450 FIL)[5]
Symptoms when wetBubbling and popping at the nozzle, stringing and a rough surface[21]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[21]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[19]
Storage requirementSealed with desiccant; Polymaker groups PETG with the highly hygroscopic materials[21][16]Not documented
Mechanical Properties
Tensile strength (XY)MPa43–44 at yield and 45–46 at break (ISO 527, injection-moulded resin data from Spectrum and Extrudr); 48 on My Tech Fun printed bars[1][2][22]60-100 (printed XY): Victrex AM 450 FIL 60-80 at yield and 3DXTech 100, both ISO 527; 98 at yield injection-moulded[3][5]
Young's modulusMPaNot documented3000-4000 (printed XY, ISO 527, Victrex AM 450 FIL); 3720 (3DXTech); 4000 injection-moulded[3][5]
Elongation at break%215–220 at break on moulded specimens (ISO 527); 4.3–4.4 at yield[1][2]28 (printed XY, ISO 527) — remarkably ductile for a high-temperature polymer[3]
Flexural strengthMPaNot documented130 (printed XY, ISO 178)[3]
Flexural modulusMPaNot documented2700 (printed XY, ISO 178)[3]
Charpy impact, notchedkJ/m²93–94 notched Izod at 23 °C on moulded specimens (ISO 180); 3DXTech quotes 8 by ISO 180/A[1][2][4]6.0 (injection-moulded, ISO 179/1eA); unnotched does not break[5]
Other impact dataIzod 4.14 kJ/m² on My Tech Fun printed bars, against 3.37 for PETG on the same rig[22]Izod notched 7.0 kJ/m2 injection-moulded (ISO 180/A). Printed anisotropy is extreme: VICTREX AM 200 on a Stratasys F900 gives Izod notched 1380-1530 J/m XZ against 30-62 J/m ZX (ASTM D256)[5][23]
Layer adhesion / Z tensileMPa21.6 on My Tech Fun 4×4 mm printed bars, against 32.9 for PETG[22]20-85 at yield (printed ZX, ISO 527, Victrex AM 450 FIL); the spread is set by chamber temperature and weld quality[5]
Brittleness1–5Tough — absorbs impact, yields before breaking[1][2]Tough — absorbs impact, yields before breaking[3]
Hardness (scale-specific)Shore A / Shore D / Rockwell69 Shore D measured by My Tech Fun, against 72 for PETG[22]Shore D 84.5 (injection-moulded, ISO 868); Rockwell M100 / R125 on extruded PEEK stock (ASTM D785)[5][24]
Creep resistance / sustained load1–5Below average — a 12 mm bar sagged to 19.4 mm over 5 days at 1.25 kg, slightly worse than PETG's 18.2[22]Excellent — holds load for years. Victrex rates PEEK for long-term creep; injection-moulded flexural stress at 3.5 % strain falls only from 125 MPa at 23 °C to 85 MPa at 125 °C, and extruded stock is rated to 249 °C continuous[25][5][24]
Fatigue / repeated-flex resistance1–5Good — 215 % elongation at break and 94 kJ/m² notched Izod on moulded specimens (Extrudr, Spectrum)[1][2]Excellent — living hinges viable. Victrex rates PEEK for long-term fatigue as well as creep[25]
Elasticity / flexibility1–5Slightly flexible in thin sections[22]Rigid[3]
Z strength as % of XY%Not documented71-84 (VICTREX AM 200 LMPAEK printed on the Stratasys F900 and Fortus 450mc, ZX against XZ tensile yield, ASTM D638); unfilled PEEK's own ZX spread is wider[23]
Thermal Properties
HDT at 0.45 MPa°CNot documented140 (printed XY, ISO 75 at 0.45 MPa, 3DXTech)[3]
HDT at 1.8 MPa°CNot documented152 (unannealed, ISO 75-2/Af, Victrex AM 450 FIL); 160 on extruded stock (ASTM D648 at 264 psi)[5][24]
Glass transition (Tg)°C78 (3DXTech, DSC)[4]143 (DSC, 3DXTech); Victrex gives onset 143 and midpoint 150 (ISO 11357-2)[3][5]
Melting point / Vicat°CAmorphous — no melting point; Vicat 88 (Spectrum, Extrudr)[1][2]343 melting (ISO 11357-3, Victrex); VICTREX AM 200 LMPAEK melts at 303[5][23]
Continuous service temperature°C68 — loaded bars begin to move at this temperature, against 65 for PETG[22]240 UL 746B relative thermal index, strength (RTI electrical 260, impact 180); Ensinger rates extruded PEEK stock at 249 long term[5][24]
Thermal expansion (CTE)µm/m·KNot documented37.8 (extruded PEEK stock, 23-60 °C, ASTM E831; source states 2.1e-5 in/in/°F), rising to 41.9 at 60-100 °C and 55.8 at 100-150 °C[24]
Flammability / UL 94Flammable; no UL 94 rating published for standard grades[26]UL 94 V-0 at 1.5 mm on the base resin; glow-wire flammability index 960 °C at 2.0 mm (IEC 60695-2-12)[3][5]
Environment & Chemical
Chemical resistanceWithstands acids, alkalis, oils and UV exposure[16]Outstanding — resistant to almost all solvents and to steam sterilisation[3]
Water / humidity resistance in service1–5Good — minor absorption; Spectrum describes the polymer as hydrophobic[1]Excellent — essentially unaffected; 0.45 % water at saturation and resistant to steam sterilisation[5][3]
Food contactNot certified for food contact as filament[16]Not documented
Biodegradability / compostabilityNot biodegradable[16]Not documented
RecyclabilityNot accepted in household plastic collection[16]Not documented
Electrical & ESD propertiesSurface resistance above 10¹³ ohm/sq — insulating (3DXTech, ASTM D257)[4]Not documented
Health & Safety
Fume toxicity1–5Moderate — measurable VOCs and UFPs, ventilation advised[27]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[27]
Ventilation / filtration requirement1–5Open a window / occasional ventilation[27]Ventilated room or enclosure recommended[27]
Post-Processing
Sanding & machiningSands poorly — the material is tough and gums rather than powders[20]Not documented
Gluing & solvent weldingCyanoacrylate; no common solvent welds PETG cleanly[20]Not documented
Vapour / chemical smoothingNo practical vapour smoothing[20]Not documented
Support material pairingPrints its own supports; Polymaker rates PolyDissolve S1 for PETG[20]Not documented
Dimensional accuracy & detailOptical clarity is the selling point; Extrudr recommends a layer height at most 50 % of nozzle diameter[2]Not documented
Solvents & Solubility
Soluble inNo common workshop solvent; Eastman's CHDM copolyester data shows 1,2-dichloroethane destroying it within a week.[28]95–98 wt% sulphuric acid dissolves it — 10 g per 100 mL at 40–70 °C gives a dark red solution. Laboratory route only.[29][30]
Softened or crazed byAcetone, ethyl acetate, toluene and DMF swell and soften the copolyester; methanol crazes it (Eastman, 1 y at 23 °C).[28]Concentrated nitric, hydrofluoric, hydrobromic and hydriodic acids attack it; DCM, DMSO and THF swell thin-walled sections.[31][30]
Solvent welding & smoothing agentDichloromethane brushed on is the only agent that smooths PETG — a controlled carcinogen, not workshop stock.[32]None — no solvent softens PEEK, so parts are joined thermally or mechanically, never chemically.[31][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. Spectrum Premium PCTG Technical Data Sheet Spectrum Filaments · 2026-08 · tds
  2. Extrudr PCTG technical data Extrudr · 2026-08 · tds
  3. ThermaX PEEK Technical Data Sheet v3 3DXTech · 2026-08 · tds
  4. MAX-G PCTG Technical Data Sheet 3DXTech · 2026-08 · tds
  5. VICTREX AM 450 FIL — datasheet Victrex · 2025-12 · tds
  6. Push Plastic product catalogue Push Plastic · 2026-08 · vendor
  7. Proto-pasta product catalogue Proto-pasta · 2026-08 · vendor
  8. 3DXTech product catalogue 3DXTech · 2026-08 · vendor
  9. 3D4Makers product catalogue 3D4Makers · 2026-08 · vendor
  10. IEMAI 3D PEEK 3D Printing Filament — store page IEMAI 3D · 2026-08 · vendor
  11. CHCKX 10KG Multicolor PCTG Filament bundle CHCKX (Amazon US) · 2026-08 · vendor
  12. Atomic Filament product catalogue Atomic Filament · 2026-08 · vendor
  13. Prusament PEI 1010 Technical Datasheet v1.0 Prusa Polymers · 2024-09 · tds
  14. Prusament PEI 1010 — material page Prusa Polymers · 2026-08 · doc
  15. Prusament PETG Technical Datasheet v1.1 Prusa Polymers · 2022-02 · tds
  16. PETG — material basics Polymaker Wiki · 2026-08 · doc
  17. Max volumetric speed Prusa Knowledge Base · 2026-08 · doc
  18. MAX-G PCTG — product page (print recommendations) 3DXTech · 2026-08 · doc
  19. ThermaX PEEK — product page 3DXTech · 2026-08 · vendor
  20. PET and PETG — Ultimate 3D Printing Materials Guide Simplify3D · 2026-08 · doc
  21. Wet Filament — signs, causes and drying Polymaker Wiki · 2026-08 · doc
  22. PCTG vs PETG comparison — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  23. VICTREX AM 200 — FDM Material Data Sheet Stratasys · 2024-04 · tds
  24. TECAPEEK natural (PEEK) — stock shape properties Ensinger · 2026-08 · tds
  25. PEEK polymers — product overview Victrex · 2026-08 · doc
  26. Prusament PETG V0 Technical Datasheet Prusa Polymers · 2026-08 · tds
  27. 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
  28. Eastman Spectar copolyester — Chemical resistance (unstressed bars, 1 year at 23 °C) Eastman Chemical Company · 2026-08 · tds
  29. The Effects of Sulfonated Poly(ether ether ketone) Ion Exchange Preparation Conditions on Membrane Properties Yee, Zhang & Ladewig, Membranes 3(3) 182–195 · 2013-07 · paper
  30. Chemical resistance — resistance of Ensinger plastics to chemicals (DIN 50 014, 23/50) Ensinger · 2026-08 · tds
  31. What solvents are not compatible with PEEK? — fluidics technical FAQ IDEX Health & Science · 2026-08 · doc
  32. Improve your 3D prints with chemical smoothing Prusa Research · 2026-08 · doc