3D Printing Info

Filament comparison

PCTG vs PLA Silk

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

PCTG guideSilk PLA guide

2 selected · all documented properties

Open these two in the interactive comparisonMore PCTG comparisonsMore PLA Silk comparisons
PCTG vs PLA Silk — documented properties and sources
PropertyPCTGPETGSilk PLAPLA
Market snapshot
Listing priceUSD/kg; dated snapshots$34.99/kg median; $14.00–$50.67/kg across 5 dated product listings$19.49/kg median; $9.75–$24.99/kg across 15 dated product listings
Identity & Market
Base polymer / chemistryPoly(cyclohexylenedimethylene terephthalate) glycol — a copolyester with a higher cyclohexanedimethanol content than PETG[1][2]PLA with a gloss-forming additive package; suppliers publish the composition as polylactic acid only[3]
Densityg/cm³1.23 (Extrudr, ASTM D792; 3DXTech, ISO 1183)[2][4]1.27 (ISO 1183)[3]
Typical priceUSD/kg1 kg spools cluster near 34[5][4][6]Mainstream 1 kg spools cluster near 20[7][8][9]
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[5][4][10]10–25 across brands; CHCKX 10 in a 16-roll bundle, SUNLU 13, LANDU 18, YXPOLYER 20, Polymaker 22, Devil Design 25[11][12][13][14][15]
Market availability1–5Available from several mainstream brands[5][4][6][16]Stocked by most mainstream brands[7][11][17]
Spool sizes & diameters1.75 and 2.85 mm; 0.5, 0.75, 1, 3 and 5 kg spools[5][6][4]1.75 mm; 1 and 1.1 kg spools; dual- and tri-colour coextruded variants[18][19]
Typical applicationsTransparent covers, guards and impact-loaded parts where PETG cracks[1][2]Decorative prints where surface gloss matters more than strength[3]
Diameter tolerance± mmNot documented±0.03 (Bambu Lab)[20]
Printing Parameters
Nozzle temperature°C250–270 (Spectrum, Extrudr)[1][2]210–240 — 20 °C above the plain PLA window[3]
Bed temperature°C60–100 (Spectrum)[1]35–45[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]Open frame is fine[3][21]
Part cooling fanUp to 100 % (Spectrum); 20–50 % (Extrudr)[1][2]Fan on[3]
Bed surface & adhesion aidTextured PEI, satin or powder-coated sheets; on smooth PEI a glue stick acts as a release agent[22][23]Cool Plate SuperTack, smooth PEI or textured PEI[3]
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][24]Not documented
Warping tendency1–5Not documentedNone[3]
Bed-adhesion difficulty1–5Needs the right surface or a thin adhesive — the problem is releasing the part, not sticking it[22][23]Sticks to anything[25]
Stringing / oozing tendency1–5Moderate — retraction tuning needed; Polymaker names stringing as PETG's common quirk[23]Not documented
Shrinkage%0.2–0.5 (Extrudr, ASTM D955)[2]Not documented
Overall printing difficulty1–5Easy — minor profile tuning[1][2]Easy — minor profile tuning; hotter nozzle and slower cap of 250 mm/s[3]
Hardware Wear & Reliability
Nozzle hardness required1–4Brass fine indefinitely — Extrudr explicitly states no hardened nozzle is needed[2]Brass fine indefinitely[21]
Abrasiveness1–5Non-abrasive[2]Non-abrasive[26][21]
Nozzle clog risk1–5Low — 3DXTech lists no special nozzle concerns and no minimum layer height for PCTG, only a 65 °C pre-dry[27]Very low[21]
Heat-creep / jam sensitivity1–5Slightly sensitive[28]Moderate — good heatbreak cooling needed; PLA softens below 60 °C[29]
Hotend requirementNo special hot-end required[28]No special hot-end required[25]
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[22][27]Moderate — 0.40 % saturated at 25 °C / 55 % RH[3]
Equilibrium moisture content at ~50 % RH%Not documented0.40 saturated at 25 °C / 55 % RH (Bambu Lab)[3]
Drying temperature & timeNot documented55 °C for 8 h in a forced-air dryer, or 65–75 °C for 12 h on an X1 heatbed[3][30]
Symptoms when wetBubbling and popping at the nozzle, stringing and a rough surface[31]Bubbling and popping at the nozzle, stringing, rough surface and weak layers[31]
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[31]Polymaker rates PLA low-sensitivity — the loss shows as poor layer adhesion and brittle layers rather than a published strength figure[31]
Storage requirementSealed with desiccant; Polymaker groups PETG with the highly hygroscopic materials[31][23]Sealed with desiccant below 20 % RH; shelf life at ambient is long[32][25]
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][33]33 (printed XY, ISO 527); eSun Silk broke 22 % below the 16-brand PLA mean on identical 4×4 mm bars[3][34]
Young's modulusMPaNot documented2130 (printed XY, ISO 527)[3]
Elongation at break%215–220 at break on moulded specimens (ISO 527); 4.3–4.4 at yield[1][2]2.8 (printed XY, ISO 527) — a quarter of PLA Basic at 12.2[3][32]
Flexural strengthMPaNot documented75 (printed XY, ISO 178)[3]
Flexural modulusMPaNot documented2460 (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]10.3 (printed XY, ISO 179, notched); unnotched 18.5[3]
Other impact dataIzod 4.14 kJ/m² on My Tech Fun printed bars, against 3.37 for PETG on the same rig[33]Not documented
Layer adhesion / Z tensileMPa21.6 on My Tech Fun 4×4 mm printed bars, against 32.9 for PETG[33]25 (printed Z, ISO 527), and flexural Z collapses to 30 against 75 in XY; eSun Silk broke at 12.3 kg where twelve of the 16 plain PLAs managed 44.6–61.5 kg[3][34][35]
Brittleness1–5Tough — absorbs impact, yields before breaking[1][2]Brittle — snaps with little warning[3]
Hardness (scale-specific)Shore A / Shore D / Rockwell69 Shore D measured by My Tech Fun, against 72 for PETG[33]Not documented
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[33]Poor — no silk-specific creep data published; plain PLA sagged from 12 to 18.7–20.3 mm over 5 days at 1.25 kg[36][37]
Fatigue / repeated-flex resistance1–5Good — 215 % elongation at break and 94 kJ/m² notched Izod on moulded specimens (Extrudr, Spectrum)[1][2]Poor — no grade-specific S-N curve; plain printed PLA ran 38 000–49 000 cycles at 30 % of tensile strength (R = 0.2)[38][29]
Elasticity / flexibility1–5Slightly flexible in thin sections[33]Rigid[3]
Z strength as % of XY%Not documented76 by tensile, 40 by flexural (printed, Bambu Lab)[3]
Thermal Properties
HDT at 0.45 MPa°CNot documented60 (ISO 75, 0.45 MPa)[3]
HDT at 1.8 MPa°CNot documented56 (ISO 75, 1.8 MPa)[3]
Glass transition (Tg)°C78 (3DXTech, DSC)[4]57 (DSC)[3]
Melting point / Vicat°CAmorphous — no melting point; Vicat 88 (Spectrum, Extrudr)[1][2]158 peak melt (DSC); Vicat 66 °C[3]
Continuous service temperature°C68 — loaded bars begin to move at this temperature, against 65 for PETG[33]50 — a loaded bar begins to move at this temperature (My Tech Fun, eSun eSilk PLA)[35]
Annealing responseNot documented50–55 °C for 6–12 h[3]
Flammability / UL 94Flammable; no UL 94 rating published for standard grades[39]Flammable; no UL 94 rating published by the major brands[32][40]
Environment & Chemical
UV resistance1–5Not documentedDegrades within weeks outdoors[29][41]
Chemical resistanceWithstands acids, alkalis, oils and UV exposure[23]Good against weak acids, oils and grease; poor against strong acids and alkalis; dissolved by chloroform, THF and hot benzene[40][29]
Water / humidity resistance in service1–5Good — minor absorption; Spectrum describes the polymer as hydrophobic[1]Good — insoluble in water[32]
Food contactNot certified for food contact as filament[23]Base resin is food-contact grade, but printed layer grooves harbour bacteria; Prusa advises against food use[29]
Biodegradability / compostabilityNot biodegradable[23]Industrially compostable only — needs sustained 55 °C; not home compostable[42][29]
RecyclabilityNot accepted in household plastic collection[23]Mechanically recyclable; not accepted in household plastic collection[42]
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[43]Low hazard — minimal VOC and particle emission[43]
Ventilation / filtration requirement1–5Open a window / occasional ventilation[43]None needed in a normal room[43]
Post-Processing
Sanding & machiningSands poorly — the material is tough and gums rather than powders[28]Wet sanding — dry sanding heats the surface by friction and smears it[41][29]
Gluing & solvent weldingCyanoacrylate; no common solvent welds PETG cleanly[28]Cyanoacrylate for most joints; some grades partially dissolve and bond with acetone[29][44]
Vapour / chemical smoothingNo practical vapour smoothing[28]No practical vapour smoothing — only chloroform, hot benzene or THF, which are laboratory-only[29]
Support material pairingPrints its own supports; Polymaker rates PolyDissolve S1 for PETG[28]Support for PLA (Bambu Lab)[3]
Dimensional accuracy & detailOptical clarity is the selling point; Extrudr recommends a layer height at most 50 % of nozzle diameter[2]55° overhangs and 30 mm bridges; gloss hides fine detail and is destroyed by sanding[3]
Solvents & Solubility
Soluble inNo common workshop solvent; Eastman's CHDM copolyester data shows 1,2-dichloroethane destroying it within a week.[45]Chloroform: 10 % w/v in 2–4 h at 23 °C, every grade and morphology; THF and DMF only at 65 °C. Laboratory reagents.[46]
Softened or crazed byAcetone, ethyl acetate, toluene and DMF swell and soften the copolyester; methanol crazes it (Eastman, 1 y at 23 °C).[45]Acetone, ethyl acetate and toluene plasticise it but dissolve <1 % even at 65 °C; submersion in acetone crazes and destroys parts.[46][47]
Solvent welding & smoothing agentDichloromethane brushed on is the only agent that smooths PETG — a controlled carcinogen, not workshop stock.[47]Chloroform vapour smooths and welds PLA at the cost of tensile strength; acetone does not smooth it at all.[48][47]

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. Bambu Filament Technical Data Sheet V1.0 — PLA Silk+ Bambu Lab · 2026-08 · tds
  4. MAX-G PCTG Technical Data Sheet 3DXTech · 2026-08 · tds
  5. Push Plastic product catalogue Push Plastic · 2026-08 · vendor
  6. Proto-pasta product catalogue Proto-pasta · 2026-08 · vendor
  7. Panchroma Silk PLA collection Polymaker Shop · 2026-08 · vendor
  8. Spectrum PLA Silk — product listing 3DJake International · 2026-08 · vendor
  9. 3DJake ecoPLA Silk Black 1.75mm 1000g 3DJake International · 2026-08 · vendor
  10. CHCKX 10KG Multicolor PCTG Filament bundle CHCKX (Amazon US) · 2026-08 · vendor
  11. Sunlu Silk PLA+ 1.75mm 1kg Sunlu Official Store · 2026-08 · vendor
  12. Bambu Lab PLA Silk 1.75mm 1kg 3D Universe · 2026-08 · vendor
  13. CHCKX 16 Pack Silk Dual Color PLA Filament Bundle CHCKX (Amazon US) · 2026-08 · vendor
  14. YXPOLYER Silk PLA Black&Gold product page YXPOLYER · 2026-08 · vendor
  15. LANDU Silk Tri-Color PLA Filament 1.75 mm 1 kg LANDU (Amazon US) · 2026-08 · vendor
  16. Atomic Filament product catalogue Atomic Filament · 2026-08 · vendor
  17. Overture Silk PLA 1.75mm Overture3D · 2026-08 · vendor
  18. eSUN PLA-Silk Magic 1.75mm eSUN Official Store · 2026-08 · vendor
  19. JAYO Silk PLA+ 1.75mm 1.1kg JAYO Official Store · 2026-08 · vendor
  20. PLA Basic — product page Bambu Lab US Store · 2026-08 · vendor
  21. Filament Material Guide Prusa Knowledge Base · 2026-08 · doc
  22. Prusament PETG Technical Datasheet v1.1 Prusa Polymers · 2022-02 · tds
  23. PETG — material basics Polymaker Wiki · 2026-08 · doc
  24. Max volumetric speed Prusa Knowledge Base · 2026-08 · doc
  25. PLA — Ultimate 3D Printing Materials Guide Simplify3D · 2026-08 · doc
  26. Prusament PLA — material page Prusa Polymers · 2026-08 · doc
  27. MAX-G PCTG — product page (print recommendations) 3DXTech · 2026-08 · doc
  28. PET and PETG — Ultimate 3D Printing Materials Guide Simplify3D · 2026-08 · doc
  29. PLA — material guide Prusa Knowledge Base · 2026-08 · doc
  30. Filament Drying Recommendations Bambu Lab Wiki · 2026-08 · doc
  31. Wet Filament — signs, causes and drying Polymaker Wiki · 2026-08 · doc
  32. Bambu Filament Technical Data Sheet V3.0 — PLA Basic Bambu Lab · 2026-08 · tds
  33. PCTG vs PETG comparison — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  34. 16 PLA brand comparison test — results spreadsheet My Tech Fun (Igor Gaspar) · 2022-10 · test
  35. Testing eSun PLA filaments: PLA-ST vs PLA+ vs Silk PLA My Tech Fun (Igor Gaspar) · 2026-08 · test
  36. BambuLab PLA Basic vs PLA Tough vs PLA-CF — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  37. PolyTerra PLA vs PLA+ — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  38. Mechanical Properties of Additively Manufactured Polymeric Materials — PLA and PETG — For Biomechanical Applications Polymers 16(13):1868 · 2024-06 · paper
  39. Prusament PETG V0 Technical Datasheet Prusa Polymers · 2026-08 · tds
  40. PolyLite PLA Technical Data Sheet V5.4 Polymaker · 2024-11 · tds
  41. Prusament PLA Technical Data Sheet v1.0 Prusa Polymers · 2018-09 · tds
  42. Filamentive PLA (recycled) — product page Filamentive · 2026-08 · vendor
  43. 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
  44. Prusament rPLA Corn Pigment 1kg — product page Prusa Research · 2026-08 · vendor
  45. Eastman Spectar copolyester — Chemical resistance (unstressed bars, 1 year at 23 °C) Eastman Chemical Company · 2026-08 · tds
  46. Solubility Study of Ingeo Biopolymer Grades in Common Organic Solvents (NWPD003) NatureWorks · 2019-10 · tds
  47. Improve your 3D prints with chemical smoothing Prusa Research · 2026-08 · doc
  48. Effect of vapour smoothing in trichloromethane on 3D printed PLA — surface, mechanical and chemical structure Pitale, Keche & Chopra, Engineering Research Express 6(4) 045579 · 2024-12 · paper