3D Printing Info

Filament comparison

Magnetic vs PETG-CF

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

Magnetic filament guideCarbon-fibre PETG (PETG-CF) guide

2 selected · all documented properties

Open these two in the interactive comparisonMore Magnetic comparisonsMore PETG-CF comparisons
Magnetic vs PETG-CF — documented properties and sources
PropertyMagnetic filamentSPECIALTYCarbon-fibre PETG (PETG-CF)PETG
Market snapshot
Listing priceUSD/kg; dated snapshots$64.99/kg median; $64.99–$64.99/kg across 1 dated product listings$29.99/kg median; $16.00–$74.22/kg across 11 dated product listings
Identity & Market
Base polymer / chemistryPLA loaded with ferromagnetic iron powder, so printed parts respond to magnets[1]PETG reinforced with chopped carbon fibre[2][3]
Densityg/cm³About 1.85 (Proto-pasta manufacturer figure) — 1.5× standard PLA[1]1.25 (Bambu Lab) to 1.34 (3DXTech), ISO 1183; Prusament 1.27[2][4][3]
Typical priceUSD/kg1 kg spools cluster near 65[5]1 kg-equivalent spools span 16–74; the middle of the market is about 29[2][6][7][8][9][10][11][12]
Price range across brandsUSD/kg64–70 across formats; 1 kg spool 65, 500 g 70, 2 kg 70[5]16–74 across brands; ELEGOO 16 in a 5 kg pack, Reli3D 17, SUNLU 20, IEMAI 22, Siraya Tech 25, Bambu Lab 32, Sakata 3D 53, 3DXTech 67, Prusament 70, Filament PM 74 on 0.5 kg spools[13][2][14][6][7][8][9][10][11][12]
Market availability1–5Niche, a handful of specialist brands[5]Stocked by most mainstream brands[2][14][6][13]
Spool sizes & diameters1.75 and 2.85 mm; 0.1, 0.5, 1 and 2 kg spools[5]1.75 and 2.85 mm; 0.75 and 1 kg spools[14][2]
Typical applicationsSensor targets, magnetic fixtures, and props that need to stick to a magnet or rust deliberately[1]Stiff functional parts and fixtures where PETG's toughness is traded for rigidity and a matte finish[2][3]
Diameter tolerance± mmNot documented±0.02 (Prusament)[3]
Printing Parameters
Nozzle temperature°C192 (Proto-pasta)[1]240–270 (Bambu Lab); 265 ± 10 (Prusament)[2][3]
Bed temperature°C60 (Proto-pasta)[1]65–75 (Bambu Lab); 90 ± 10 (Prusament)[2][3]
Enclosure / chamber requirement1–5Open frame is fine[1]Open frame fine; draught shield helps — Bambu Lab specifies a 35–50 °C chamber[2]
Recommended chamber temperature°CNot documented35–50 (Bambu Lab)[2]
Part cooling fanNot documented0–60 % (Bambu Lab); 50 % (Prusament)[2][3]
Bed surface & adhesion aidNot documentedTextured PEI or engineering plate with glue (Bambu Lab)[2]
Maximum volumetric flow (mm³/s; see test conditions)mm³/s1.6–2.4 at Proto-pasta's 20–30 mm/s on a 0.4 mm nozzle at 0.2 mm layer[1]11.5 on My Tech Fun's Bambu Lab PETG-CF profile[15]
Bed-adhesion difficulty1–5Not documentedNeeds the right surface or a thin adhesive[2]
Stringing / oozing tendency1–5Not documentedSlight — the fibre reduces stringing against unfilled PETG[2][16]
Overall printing difficulty1–5Intermediate — dry filament and a tuned profile; slow, and brittle in filament form[1]Intermediate — dry filament and a tuned profile; hardened nozzle mandatory[2]
Extruder requirementProto-pasta advises an extrusion width 0.05 mm larger than the nozzle and warns feeding is inconsistent below 0.4 mm and on Bowden machines[1]Not documented
Hardware Wear & Reliability
Nozzle hardness required1–4Brass acceptable; hardened steel for volume work[1]Hardened steel required[2]
Abrasiveness1–5Moderately abrasive — metal fill[1]Highly abrasive — standard CF composite[2]
Nozzle clog risk1–5Moderate — needs dry filament and a clean nozzle; Prusa lists metal-filled composites as a higher clogging risk and recommends a 0.6 mm nozzle minimum[17]Moderate — needs dry filament and a clean nozzle; 3DXTech specifies a hardened 0.4 mm minimum nozzle and 0.25 mm layers or higher, and Prusa lists composites as a higher clogging risk[18][19]
Heat-creep / jam sensitivity1–5Not documentedSlightly sensitive[16]
Hotend requirementProto-pasta recommends a wear-resistant or larger nozzle for longer service intervals[1]Hardened steel nozzle; no high-temperature hot-end needed[2][16]
Moisture Behaviour
Moisture absorption (hygroscopicity)1–5Not documentedLow — 0.30 % saturated at 25 °C / 55 % RH (Bambu Lab)[2]
Equilibrium moisture content at ~50 % RH%Not documented0.30 saturated at 25 °C / 55 % RH (Bambu Lab); Prusa measures 0.10 after 7 days at 22 % RH[2][3]
Drying temperature & timeNot documented65 °C for 8 h (Bambu Lab)[2]
Symptoms when wetNot documentedBubbling and popping at the nozzle, stringing and a rough surface[20]
Effect of moisture on strengthPolymaker rates PLA low-sensitivity and publishes no dry-versus-conditioned figures; absorbed water flashes to steam and shows as bubbling and poor layer adhesion[20]No dry-versus-conditioned figures published; Bambu Lab states PETG-CF must be properly dried before printing and stored dry after use[2][20]
Storage requirementNot documentedSealed with desiccant; Bambu Lab says store dry after use[2][20]
Mechanical Properties
Tensile strength (XY)MPaNot documented35 ± 5 (Bambu Lab) and 47 ± 2 at yield (Prusament) printed XY, ISO 527; 56 at break for 3DXTech[2][3][4]
Young's modulusMPaNot documented2460 ± 230 (Bambu Lab) and 1700 (Prusament) printed XY, ISO 527[2][3]
Elongation at break%Not documented4.3 at yield (Prusament, printed XY, ISO 527); 3 at break for 3DXTech[3][4]
Flexural strengthMPaNot documented68 ± 3 printed horizontal, ISO 178 (Prusament)[3]
Flexural modulusMPaNot documented2300 printed horizontal, 3100 printed vertical, ISO 178 (Prusament)[3]
Other impact dataNot documentedCharpy unnotched 29 ± 6 printed horizontal and 43 ± 8 printed vertical (Prusament, ISO 179-1); Izod 4.91 kJ/m² on My Tech Fun bars[3][15]
Layer adhesion / Z tensileMPaNot documented29 ± 4 printed Z (Bambu Lab, ISO 527); 18 ± 3 by Prusa's interlayer adhesion test; 10.7 on My Tech Fun bars[2][3][15]
Brittleness1–5Brittle — Proto-pasta describes the filament as more brittle than standard PLA and needing extra care in handling[1]Brittle — snaps with little warning[4]
Hardness (scale-specific)Shore A / Shore D / RockwellNot documented77 Shore D (Prusa Polymers method)[3]
Creep resistance / sustained load1–5Not documentedBelow average — a 12 mm bar sagged to 16.4 mm over 5 days at 1.25 kg, less than plain PETG's 19.4[15]
Fatigue / repeated-flex resistance1–5Not documentedModerate — no CF-grade S-N curve; unfilled printed PETG ran 79 000–193 000 cycles at 30 % of tensile strength[21]
Elasticity / flexibility1–5Rigid[1]Rigid[2]
Z strength as % of XY%Not documented83 (Bambu Lab, printed Z against XY tensile)[2]
Thermal Properties
HDT at 0.45 MPa°CNot documented74 (Bambu Lab) and 96 (Prusament), ISO 75 at 0.45 MPa[2][3]
HDT at 1.8 MPa°CNot documented68 (Bambu Lab) and 80 (Prusament), ISO 75 at 1.8 MPa[2][3]
Glass transition (Tg)°CNot documented68 (Bambu Lab) and 80 (3DXTech), DSC[2][4]
Melting point / Vicat°CNot documented225 melting (Bambu Lab, DSC) — the carbon fibre lets the PET fraction crystallise[2]
Continuous service temperature°CNot documented77 — loaded bars begin to move at this temperature, against 61 for Bambu Lab PETG Basic[15]
Flammability / UL 94Not documentedFlammable; no UL 94 rating published[2]
Environment & Chemical
UV resistance1–5Not documentedModerate — a season or two; the carbon fibre does not add UV stabilisation[22]
Outdoor durabilityDeliberately rustable — Proto-pasta markets the iron content as oxidising when exposed to moisture[1]Not documented
Chemical resistanceNot documentedWithstands acids, alkalis, oils and UV exposure, as for unfilled PETG[22]
Food contactNot documentedNot certified for food contact[22]
Biodegradability / compostabilityNot documentedNot biodegradable[22]
RecyclabilityNot documentedFibre-filled PETG is not accepted in household plastic collection[22]
Electrical & ESD propertiesFerromagnetic: Proto-pasta states it responds to magnets and behaves similarly to pure iron[1]Surface resistance above 10⁹ ohm/sq — carbon fibre at this loading is not static-dissipative (3DXTech)[4]
Health & Safety
Fume toxicity1–5Low hazard — minimal VOC and particle emission; none of these materials was in the chamber study[23]Moderate — measurable VOCs and UFPs, ventilation advised[23]
Ventilation / filtration requirement1–5Open a window / occasional ventilation[23]Open a window / occasional ventilation[23]
Dust & fibre handling hazardNot documentedCarbon fibre is bound in the matrix; sanding dust should not be inhaled[4]
Post-Processing
Sanding & machiningPolishing and deliberate rusting are the intended finishes[1]Sands to a matte finish more readily than unfilled PETG[16]
Gluing & solvent weldingNot documentedCyanoacrylate; no common solvent welds it[16]
Vapour / chemical smoothingNot documentedNo practical vapour smoothing[16]
Support material pairingNot documentedSupport for PLA or its own material (Bambu Lab)[2]
Dimensional accuracy & detailNot documentedMatte finish hides layer lines; stringing is reduced against unfilled PETG[2]
Solvents & Solubility
Soluble inChloroform dissolves the PLA matrix and leaves the iron powder behind; laboratory reagent, not workshop stock.[24][1]No common workshop solvent; dichloromethane — a carcinogen — dissolves the matrix surface, 1,2-dichloroethane destroys it in a week.[25][26]
Softened or crazed byAcetone and ethyl acetate plasticise the matrix rather than dissolving it; water attacks the exposed iron.[24][1]Acetone (+16 % weight over 1 year at 23 °C), ethyl acetate, toluene and DMF swell and soften it; methanol crazes it.[25]
Solvent welding & smoothing agentNone — PLA has no workshop-safe solvent, and the iron loading blocks the surface flow smoothing needs.[24]Dichloromethane reaches only the resin, so the fibre is left standing proud of the surface. Controlled carcinogen.[26]

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. Magnetic Iron PLA — product page and technical data Proto-pasta · 2026-08 · tds
  2. Bambu Filament Technical Data Sheet — PETG-CF Bambu Lab · 2026-08 · tds
  3. Prusament PETG Carbon Fiber Technical Datasheet Prusa Polymers · 2026-08 · tds
  4. CarbonX Carbon Fiber PETG Technical Data Sheet 3DXTech · 2026-08 · tds
  5. Proto-pasta product catalogue Proto-pasta · 2026-08 · vendor
  6. Printed Solid product catalogue Printed Solid · 2026-08 · vendor
  7. SUNLU PETG-CF (PETG Carbon Fiber) 3D Printer Filament 1 kg SUNLU · 2026-08 · vendor
  8. Fibreheart PETG-CF Pro Filament product page Siraya Tech · 2026-08 · vendor
  9. IEMAI CF-PETG 3D Printing Filament product page IEMAI 3D · 2026-08 · vendor
  10. Reli3D Carbon Fiber PETG Filament 1.75 mm, 1 kg Reli3D (Amazon US) · 2026-08 · vendor
  11. PET-G CF15 Sakata 3D Filaments · 2026-08 · vendor
  12. Filament PM CFJet technical data sheet (TDS CFJet ENG.pdf) Filament PM (Plasty Mladec) · 2026-08 · tds
  13. ELEGOO product catalogue ELEGOO · 2026-08 · vendor
  14. 3DXTech product catalogue 3DXTech · 2026-08 · vendor
  15. BambuLab PETG Basic vs Translucent vs PETG-CF — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  16. PET and PETG — Ultimate 3D Printing Materials Guide Simplify3D · 2026-08 · doc
  17. Composite materials with metal or wood particles Prusa Knowledge Base · 2026-08 · doc
  18. CARBONX PETG+CF — product page (print recommendations) 3DXTech · 2026-08 · doc
  19. Composite materials filled with carbon, kevlar or glass Prusa Knowledge Base · 2026-08 · doc
  20. Wet Filament — signs, causes and drying Polymaker Wiki · 2026-08 · doc
  21. Mechanical Properties of Additively Manufactured Polymeric Materials — PLA and PETG — For Biomechanical Applications Polymers 16(13):1868 · 2024-06 · paper
  22. PETG — material basics Polymaker Wiki · 2026-08 · doc
  23. 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
  24. Solubility Study of Ingeo Biopolymer Grades in Common Organic Solvents (NWPD003) NatureWorks · 2019-10 · tds
  25. Eastman Spectar copolyester — Chemical resistance (unstressed bars, 1 year at 23 °C) Eastman Chemical Company · 2026-08 · tds
  26. Improve your 3D prints with chemical smoothing Prusa Research · 2026-08 · doc