3D Printing Info

Filament comparison

PC-GF vs PLA Silk

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

Glass-fibre PC (PC-GF) guideSilk PLA guide

2 selected · all documented properties

Open these two in the interactive comparisonMore PC-GF comparisonsMore PLA Silk comparisons
PC-GF vs PLA Silk — documented properties and sources
PropertyGlass-fibre PC (PC-GF)PCSilk PLAPLA
Market snapshot
Listing priceUSD/kg; dated snapshots$71.27/kg median; $71.27–$71.27/kg across 1 dated product listings$19.49/kg median; $9.75–$24.99/kg across 15 dated product listings
Identity & Market
Base polymer / chemistryPolycarbonate reinforced with 30 wt% short glass fibre[1]PLA with a gloss-forming additive package; suppliers publish the composition as polylactic acid only[2]
Densityg/cm³1.17 (measured on a 100 % infill printed part, ISO 1183-A)[1]1.27 (ISO 1183)[2]
Typical priceUSD/kg1 kg spools cluster near 71[3]Mainstream 1 kg spools cluster near 20[4][5][6]
Price range across brandsUSD/kg71 — BASF Ultrafuse PC GF30 at igo3d is the only priced listing found; Owens Corning sells XSTRAND GF30-PC in 500 g and 1 kg[3][1]10–25 across brands; CHCKX 10 in a 16-roll bundle, SUNLU 13, LANDU 18, YXPOLYER 20, Polymaker 22, Devil Design 25[7][8][9][10][11]
Market availability1–5Niche, a handful of specialist brands — neither Polymaker's nor 3DXTech's polycarbonate range contains a glass-fibre grade, but BASF Forward AM and Owens Corning both sell one through European retail[3][1][12][13]Stocked by most mainstream brands[4][7][14]
Spool sizes & diameters1.75 and 2.85 mm at +/- 0.05 mm; 500 g and 1 kg net spools[1]1.75 mm; 1 and 1.1 kg spools; dual- and tri-colour coextruded variants[15][16]
Typical applicationsFunctional prototyping for mechanical engineering, electronics and automotive[1]Decorative prints where surface gloss matters more than strength[2]
Diameter tolerance± mm+/- 0.05 (Owens Corning XSTRAND)[1]±0.03 (Bambu Lab)[17]
Printing Parameters
Nozzle temperature°C280-330 (Owens Corning XSTRAND GF30-PC)[1]210–240 — 20 °C above the plain PLA window[2]
Bed temperature°C80-110 (Owens Corning XSTRAND GF30-PC)[1]35–45[2]
Enclosure / chamber requirement1–5Enclosure required (passive) — as for unfilled PC[18][19]Open frame is fine[2][20]
Part cooling fanNot documentedFan on[2]
Bed surface & adhesion aidPerforated plate, DimaFix or Magigoo PC glue (Owens Corning)[1]Cool Plate SuperTack, smooth PEI or textured PEI[2]
Warping tendency1–5Not documentedNone[2]
Bed-adhesion difficulty1–5Not documentedSticks to anything[21]
Overall printing difficulty1–5Not documentedEasy — minor profile tuning; hotter nozzle and slower cap of 250 mm/s[2]
Extruder requirementOwens Corning specifies a nozzle above 0.4 mm and hardened steel nozzles and drive wheels[1]Not documented
Hardware Wear & Reliability
Nozzle hardness required1–4Hardened steel required — Owens Corning states glass reinforcement shortens brass nozzle and drive-wheel life[1]Brass fine indefinitely[20]
Abrasiveness1–5Highly abrasive — 30 wt% glass fibre[1]Non-abrasive[22][20]
Nozzle clog risk1–5High — jams from moisture, heat creep or particles; PC already absorbs water from the air and Prusa lists glass-filled composites as a higher clogging risk[23][24]Very low[20]
Heat-creep / jam sensitivity1–5Not documentedModerate — good heatbreak cooling needed; PLA softens below 60 °C[25]
Hotend requirementNot documentedNo special hot-end required[21]
Moisture Behaviour
Moisture absorption (hygroscopicity)1–5Negligible (<0.1 % EMC) — Owens Corning measures below 0.1 % at 23 °C and 50 % RH (ISO 62)[1]Moderate — 0.40 % saturated at 25 °C / 55 % RH[2]
Equilibrium moisture content at ~50 % RH%Below 0.1 at 23 °C and 50 % RH, and below 0.1 at saturation (ISO 62)[1]0.40 saturated at 25 °C / 55 % RH (Bambu Lab)[2]
Drying temperature & timeNot documented55 °C for 8 h in a forced-air dryer, or 65–75 °C for 12 h on an X1 heatbed[2][26]
Symptoms when wetNot documentedBubbling and popping at the nozzle, stringing, rough surface and weak layers[27]
Effect of moisture on strengthNo dry-versus-conditioned figures are published. Polymaker calls PC highly hygroscopic; absorbed water flashes to steam and shows as bubbling and poor layer adhesion[28][27]Polymaker rates PLA low-sensitivity — the loss shows as poor layer adhesion and brittle layers rather than a published strength figure[27]
Storage requirementNot documentedSealed with desiccant below 20 % RH; shelf life at ambient is long[29][21]
Mechanical Properties
Tensile strength (XY)MPa65 at break (printed, ISO 527 at 1 mm/min)[1]33 (printed XY, ISO 527); eSun Silk broke 22 % below the 16-brand PLA mean on identical 4×4 mm bars[2][30]
Young's modulusMPa5400 (printed, ISO 527 at 1 mm/min)[1]2130 (printed XY, ISO 527)[2]
Elongation at break%2.5 at break (printed, ISO 527 at 1 mm/min)[1]2.8 (printed XY, ISO 527) — a quarter of PLA Basic at 12.2[2][29]
Flexural strengthMPa113 at yield (printed, ISO 178 at 2 mm/min)[1]75 (printed XY, ISO 178)[2]
Flexural modulusMPa5500 (printed, ISO 178 at 2 mm/min)[1]2460 (printed XY, ISO 178)[2]
Charpy impact, notchedkJ/m²Not documented10.3 (printed XY, ISO 179, notched); unnotched 18.5[2]
Layer adhesion / Z tensileMPaNot documented25 (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[2][30][31]
Brittleness1–5Brittle — snaps with little warning; 2.5 % elongation at break[1]Brittle — snaps with little warning[2]
Hardness (scale-specific)Shore A / Shore D / RockwellRockwell 70 (118) — the source does not name the scales and Shore D 79 on extruded unfilled PC stock (ASTM D785, D2240); no figure is published for a glass-fibre grade[32]Not documented
Creep resistance / sustained load1–5Excellent — holds load for years. Room-temperature tensile creep of moulded unfilled PC ran unbroken at 41 MPa until the test was stopped, and 30 wt% glass raises the tensile modulus from about 2.3 to 5.4 GPa[33][1]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[34][35]
Fatigue / repeated-flex resistance1–5Not documentedPoor — no grade-specific S-N curve; plain printed PLA ran 38 000–49 000 cycles at 30 % of tensile strength (R = 0.2)[36][25]
Elasticity / flexibility1–5Rigid[1]Rigid[2]
Z strength as % of XY%Not documented76 by tensile, 40 by flexural (printed, Bambu Lab)[2]
Thermal Properties
HDT at 0.45 MPa°CNot documented60 (ISO 75, 0.45 MPa)[2]
HDT at 1.8 MPa°C137 (printed, ISO 75 Method A at 1.8 MPa)[1]56 (ISO 75, 1.8 MPa)[2]
Glass transition (Tg)°C145 (DSC, ISO 11357)[1]57 (DSC)[2]
Melting point / Vicat°C270 stated as melting point (ISO 11357) — unusual for an amorphous polymer, but this is the published figure[1]158 peak melt (DSC); Vicat 66 °C[2]
Continuous service temperature°CNot documented50 — a loaded bar begins to move at this temperature (My Tech Fun, eSun eSilk PLA)[31]
Annealing responseNot documented50–55 °C for 6–12 h[2]
Thermal expansion (CTE)µm/m·K26.2 in XY and 77.4 in Z (printed, ISO 11359-2) — a threefold anisotropy, and the lowest in-plane expansion of any polycarbonate here[1]Not documented
Flammability / UL 94UL 94 V-0 verified (Owens Corning)[1]Flammable; no UL 94 rating published by the major brands[29][37]
Environment & Chemical
UV resistance1–5Good — years with some colour shift. Owens Corning lists UV resistance as a product benefit but publishes no exposure data[1]Degrades within weeks outdoors[25][38]
Chemical resistanceNot documentedGood against weak acids, oils and grease; poor against strong acids and alkalis; dissolved by chloroform, THF and hot benzene[37][25]
Water / humidity resistance in service1–5Excellent — essentially unaffected; below 0.1 % water at saturation (ISO 62)[1]Good — insoluble in water[29]
Food contactNot documentedBase resin is food-contact grade, but printed layer grooves harbour bacteria; Prusa advises against food use[25]
Biodegradability / compostabilityNot documentedIndustrially compostable only — needs sustained 55 °C; not home compostable[39][25]
RecyclabilityNot documentedMechanically recyclable; not accepted in household plastic collection[39]
Electrical & ESD propertiesElectrically insulating (Owens Corning)[1]Not documented
Health & Safety
Fume toxicity1–5Moderate — measurable VOCs and UFPs, ventilation advised[40]Low hazard — minimal VOC and particle emission[40]
Ultrafine-particle emission rateparticles/min≈4 × 10¹⁰ median — the highest ultrafine-particle rate of the nine filaments in the chamber study, above every ABS tested[40]Not documented
Ventilation / filtration requirement1–5Ventilated room or enclosure recommended[40][19]None needed in a normal room[40]
Dust & fibre handling hazardOwens Corning warns that the glass reinforcement is abrasive when melted and advises sufficient ventilation and avoiding extrusion fumes[1]Not documented
Post-Processing
Sanding & machiningNot documentedWet sanding — dry sanding heats the surface by friction and smears it[38][25]
Gluing & solvent weldingNot documentedCyanoacrylate for most joints; some grades partially dissolve and bond with acetone[25][41]
Vapour / chemical smoothingNot documentedNo practical vapour smoothing — only chloroform, hot benzene or THF, which are laboratory-only[25]
Support material pairingNot documentedSupport for PLA (Bambu Lab)[2]
Dimensional accuracy & detailHigh dimensional stability is the headline benefit; the 26.2 um/m*K in-plane CTE is a third of unfilled PC's[1]55° overhangs and 30 mm bridges; gloss hides fine detail and is destroyed by sanding[2]
Solvents & Solubility
Soluble inDichloromethane and chloroform dissolve the matrix and leave the fibre; DMF and dioxane do the same (Covestro).[42]Chloroform: 10 % w/v in 2–4 h at 23 °C, every grade and morphology; THF and DMF only at 65 °C. Laboratory reagents.[43]
Softened or crazed byMethanol, butyl acetate, ether, 1 % NaOH and phthalate plasticisers stress-crack it; acetone, MEK and xylene swell it.[42]Acetone, ethyl acetate and toluene plasticise it but dissolve <1 % even at 65 °C; submersion in acetone crazes and destroys parts.[43][44]
Solvent welding & smoothing agentDichloromethane cement welds the resin, but the fibre keeps the joint from flowing closed. Controlled carcinogen.[45]Chloroform vapour smooths and welds PLA at the cost of tensile strength; acetone does not smooth it at all.[46][44]

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. XSTRAND GF30-PC Data Sheet Owens Corning · 2019-04 · tds
  2. Bambu Filament Technical Data Sheet V1.0 — PLA Silk+ Bambu Lab · 2026-08 · tds
  3. BASF Ultrafuse PC GF30 Black 2.85 mm 1.000 g igo3d · 2026-08 · vendor
  4. Panchroma Silk PLA collection Polymaker Shop · 2026-08 · vendor
  5. Spectrum PLA Silk — product listing 3DJake International · 2026-08 · vendor
  6. 3DJake ecoPLA Silk Black 1.75mm 1000g 3DJake International · 2026-08 · vendor
  7. Sunlu Silk PLA+ 1.75mm 1kg Sunlu Official Store · 2026-08 · vendor
  8. Bambu Lab PLA Silk 1.75mm 1kg 3D Universe · 2026-08 · vendor
  9. CHCKX 16 Pack Silk Dual Color PLA Filament Bundle CHCKX (Amazon US) · 2026-08 · vendor
  10. YXPOLYER Silk PLA Black&Gold product page YXPOLYER · 2026-08 · vendor
  11. LANDU Silk Tri-Color PLA Filament 1.75 mm 1 kg LANDU (Amazon US) · 2026-08 · vendor
  12. Polymaker product catalogue Polymaker · 2026-08 · vendor
  13. 3DXTech product catalogue 3DXTech · 2026-08 · vendor
  14. Overture Silk PLA 1.75mm Overture3D · 2026-08 · vendor
  15. eSUN PLA-Silk Magic 1.75mm eSUN Official Store · 2026-08 · vendor
  16. JAYO Silk PLA+ 1.75mm 1.1kg JAYO Official Store · 2026-08 · vendor
  17. PLA Basic — product page Bambu Lab US Store · 2026-08 · vendor
  18. PolyLite PC Technical Data Sheet V5.4 Polymaker · 2024-11 · tds
  19. ABS / ASA / PC Usage Guide Bambu Lab Wiki · 2026-08 · doc
  20. Filament Material Guide Prusa Knowledge Base · 2026-08 · doc
  21. PLA — Ultimate 3D Printing Materials Guide Simplify3D · 2026-08 · doc
  22. Prusament PLA — material page Prusa Polymers · 2026-08 · doc
  23. Composite materials filled with carbon, kevlar or glass Prusa Knowledge Base · 2026-08 · doc
  24. Polycarbonate — Ultimate 3D Printing Materials Guide Simplify3D · 2026-08 · doc
  25. PLA — material guide Prusa Knowledge Base · 2026-08 · doc
  26. Filament Drying Recommendations Bambu Lab Wiki · 2026-08 · doc
  27. Wet Filament — signs, causes and drying Polymaker Wiki · 2026-08 · doc
  28. PC — material basics Polymaker Wiki · 2026-08 · doc
  29. Bambu Filament Technical Data Sheet V3.0 — PLA Basic Bambu Lab · 2026-08 · tds
  30. 16 PLA brand comparison test — results spreadsheet My Tech Fun (Igor Gaspar) · 2022-10 · test
  31. Testing eSun PLA filaments: PLA-ST vs PLA+ vs Silk PLA My Tech Fun (Igor Gaspar) · 2026-08 · test
  32. TECANAT natural (PC) — stock shape properties Ensinger · 2026-08 · tds
  33. Experimental data for creep and dynamic mechanical properties of polycarbonate and polycarbonate/ABS Data in Brief 42:108264 · 2022-06 · paper
  34. BambuLab PLA Basic vs PLA Tough vs PLA-CF — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  35. PolyTerra PLA vs PLA+ — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  36. Mechanical Properties of Additively Manufactured Polymeric Materials — PLA and PETG — For Biomechanical Applications Polymers 16(13):1868 · 2024-06 · paper
  37. PolyLite PLA Technical Data Sheet V5.4 Polymaker · 2024-11 · tds
  38. Prusament PLA Technical Data Sheet v1.0 Prusa Polymers · 2018-09 · tds
  39. Filamentive PLA (recycled) — product page Filamentive · 2026-08 · vendor
  40. 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
  41. Prusament rPLA Corn Pigment 1kg — product page Prusa Research · 2026-08 · vendor
  42. Makrolon — The chemical resistance (Makrolon 2800, 6 days at 23 °C and 50 °C) Covestro · 2016-12 · tds
  43. Solubility Study of Ingeo Biopolymer Grades in Common Organic Solvents (NWPD003) NatureWorks · 2019-10 · tds
  44. Improve your 3D prints with chemical smoothing Prusa Research · 2026-08 · doc
  45. Weld-On 3 Acrylic Plastic Cement — technical data sheet (shipped as dichloromethane) IPS Corporation · 2002-07 · tds
  46. 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