3D Printing InfoFilament comparison
Magnetic vs rPETG
Compare printing settings, strength, heat resistance, dated prices and sources.
2 selected · all documented properties
| Property | Magnetic filamentSPECIALTY | Recycled PETG (rPETG)PETG |
|---|---|---|
| Market snapshot | ||
| Listing priceUSD/kg; dated snapshots | $64.99/kg median; $64.99–$64.99/kg across 1 dated product listings | $28.99/kg median; $17.24–$39.98/kg across 4 dated product listings |
| Identity & Market | ||
| Base polymer / chemistry | PLA loaded with ferromagnetic iron powder, so printed parts respond to magnets[1] | PETG regranulated from recycled polyester waste; Polymaker's Fiberon PETG-rCF08 adds 8 wt% recycled carbon fibre[2][3][4] |
| Densityg/cm³ | About 1.85 (Proto-pasta manufacturer figure) — 1.5× standard PLA[1] | 1.27 (Prusament) and 1.30 (Fiberon PETG-rCF08), ISO 1183[2][4] |
| Typical priceUSD/kg | 1 kg spools cluster near 65[5] | 1 kg spools cluster near 29[6][7][8][9] |
| Price range across brandsUSD/kg | 64–70 across formats; 1 kg spool 65, 500 g 70, 2 kg 70[5] | 17–40 across brands; Filament PM RePETG 17, 3DXTech ECOMAX 26, GreenGate3D 32, Fiberon rCF08 40[6][7][8][9] |
| Market availability1–5 | Niche, a handful of specialist brands[5] | Available from several mainstream brands[6][7][8] |
| Spool sizes & diameters | 1.75 and 2.85 mm; 0.1, 0.5, 1 and 2 kg spools[5] | 1.75 and 2.85 mm; 0.5, 1 and 3 kg spools[8][7] |
| Typical applications | Sensor targets, magnetic fixtures, and props that need to stick to a magnet or rust deliberately[1] | Not documented |
| Diameter tolerance± mm | Not documented | ±0.05 (Prusament PETG Recycled), against ±0.02 for virgin Prusament PETG[2][10] |
| Printing Parameters | ||
| Nozzle temperature°C | 192 (Proto-pasta)[1] | 250 ± 10 (Prusament); 230–255 (Spectrum)[2][3] |
| Bed temperature°C | 60 (Proto-pasta)[1] | 80 ± 10 (Prusament); 60–80 (Spectrum)[2][3] |
| Enclosure / chamber requirement1–5 | Open frame is fine[1] | Open frame is fine — Spectrum states a closed chamber is not necessary[3] |
| Part cooling fan | Not documented | 50 % (Prusament); up to 100 % (Spectrum)[2][3] |
| Bed surface & adhesion aid | Not documented | Textured PEI, satin or powder-coated sheets; on smooth PEI a glue stick acts as a release agent[10][11] |
| Maximum volumetric flow (mm³/s; see test conditions)mm³/s | 1.6–2.4 at Proto-pasta's 20–30 mm/s on a 0.4 mm nozzle at 0.2 mm layer[1] | Not documented |
| Bed-adhesion difficulty1–5 | Not documented | Needs the right surface or a thin adhesive — the problem is releasing the part, not sticking it[10][11] |
| Stringing / oozing tendency1–5 | Not documented | Moderate — retraction tuning needed; Polymaker names stringing as PETG's common quirk[11] |
| Overall printing difficulty1–5 | Intermediate — dry filament and a tuned profile; slow, and brittle in filament form[1] | Easy — minor profile tuning; Spectrum describes printing as similar to standard PETG[3] |
| Extruder requirement | Proto-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 required1–4 | Brass acceptable; hardened steel for volume work[1] | Brass fine indefinitely[2] |
| Abrasiveness1–5 | Moderately abrasive — metal fill[1] | Not documented |
| Nozzle clog risk1–5 | Moderate — 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[12] | Low — recycled PETG prints on the same hardware as virgin PETG: no special hot-end, no drybox and no hardened nozzle[13][14] |
| Heat-creep / jam sensitivity1–5 | Not documented | Slightly sensitive[13] |
| Hotend requirement | Proto-pasta recommends a wear-resistant or larger nozzle for longer service intervals[1] | No special hot-end required[13] |
| Moisture Behaviour | ||
| Moisture absorption (hygroscopicity)1–5 | Not documented | Moderate (0.3–0.8 %) — recycled PETG shares the virgin matrix, which reaches 0.40 % saturated at 25 °C / 55 % RH[10] |
| Equilibrium moisture content at ~50 % RH% | Not documented | 0.07 after 24 h and 0.10 after 7 days at 24 °C / 22 % RH (Prusa Polymers)[2] |
| Symptoms when wet | Not documented | Bubbling and popping at the nozzle, stringing and a rough surface[15] |
| Effect of moisture on strength | Polymaker rates PLA low-sensitivity and publishes no dry-versus-conditioned figures; absorbed water flashes to steam and shows as bubbling and poor layer adhesion[15] | Polymaker 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[15] |
| Storage requirement | Not documented | Sealed with desiccant; Polymaker groups PETG with the highly hygroscopic materials[15][11] |
| Mechanical Properties | ||
| Tensile strength (XY)MPa | Not documented | 43 ± 1.8 printed horizontal at yield, ISO 527-1 (Prusament), against 47 ± 2 for virgin Prusament PETG; Spectrum quotes 52 at yield on moulded specimens[2][10][3] |
| Young's modulusMPa | Not documented | 1500 printed horizontal, 1600 printed vertical (Prusament, ISO 527-1) — the same as virgin Prusament PETG[2][10] |
| Elongation at break% | Not documented | 4.5 at yield printed (Prusament); Spectrum quotes 400 at break on moulded specimens[2][3] |
| Flexural strengthMPa | Not documented | 63 ± 1 printed horizontal, ISO 178 (Prusament), against 66 ± 2 for virgin Prusament PETG[2][10] |
| Flexural modulusMPa | Not documented | 1800 printed horizontal, ISO 178 (Prusament)[2] |
| Charpy impact, notchedkJ/m² | Not documented | 12 ± 1 printed horizontal and 15 ± 3 printed vertical, ISO 179-1 notched (Prusament)[2] |
| Other impact data | Not documented | Charpy unnotched 25 ± 3 printed horizontal and 38 ± 11 printed vertical (Prusament, ISO 179-1)[2] |
| Layer adhesion / Z tensileMPa | Not documented | 15 ± 5 (Prusa Polymers interlayer adhesion test), against 18 ± 4 for virgin Prusament PETG[2][10] |
| Brittleness1–5 | Brittle — Proto-pasta describes the filament as more brittle than standard PLA and needing extra care in handling[1] | Moderate[2] |
| Hardness (scale-specific)Shore A / Shore D / Rockwell | Not documented | 74 Shore D (Prusa Polymers method) — the same as virgin Prusament PETG[2][10] |
| Creep resistance / sustained load1–5 | Not documented | Below average — no recycled-grade creep test; virgin PETG sagged from 12 to 17.1–20.4 mm over 5 days at 1.25 kg[16][17][18][19] |
| Fatigue / repeated-flex resistance1–5 | Not documented | Moderate — no recycled-grade S-N curve; virgin printed PETG ran 79 000–193 000 cycles at 30 % of tensile strength[20] |
| Elasticity / flexibility1–5 | Rigid[1] | Slightly flexible in thin sections[2] |
| Thermal Properties | ||
| HDT at 0.45 MPa°C | Not documented | 68 (ISO 75, 0.45 MPa) — the same as virgin Prusament PETG; Spectrum quotes 70[2][10][3] |
| HDT at 1.8 MPa°C | Not documented | 68 (ISO 75, 1.8 MPa)[2] |
| Flammability / UL 94 | Not documented | Flammable; no UL 94 rating published for standard grades[21] |
| Environment & Chemical | ||
| Outdoor durability | Deliberately rustable — Proto-pasta markets the iron content as oxidising when exposed to moisture[1] | Not documented |
| Chemical resistance | Not documented | Withstands acids, alkalis, oils and UV exposure[11] |
| Food contact | Not documented | Not certified for food contact as filament[11] |
| Biodegradability / compostability | Not documented | Not biodegradable[11] |
| Recyclability | Not documented | The feedstock itself — Spectrum describes collecting, shredding and re-homogenising PETG waste[3] |
| Electrical & ESD properties | Ferromagnetic: Proto-pasta states it responds to magnets and behaves similarly to pure iron[1] | Not documented |
| Health & Safety | ||
| Fume toxicity1–5 | Low hazard — minimal VOC and particle emission; none of these materials was in the chamber study[22] | Moderate — measurable VOCs and UFPs, ventilation advised[22] |
| Ventilation / filtration requirement1–5 | Open a window / occasional ventilation[22] | Open a window / occasional ventilation[22] |
| Post-Processing | ||
| Sanding & machining | Polishing and deliberate rusting are the intended finishes[1] | Sands poorly — the material is tough and gums rather than powders[13] |
| Gluing & solvent welding | Not documented | Cyanoacrylate; no common solvent welds PETG cleanly[13] |
| Vapour / chemical smoothing | Not documented | No practical vapour smoothing[13] |
| Support material pairing | Not documented | Prints its own supports; Polymaker rates PolyDissolve S1 for PETG[13] |
| Solvents & Solubility | ||
| Soluble in | Chloroform dissolves the PLA matrix and leaves the iron powder behind; laboratory reagent, not workshop stock.[23][1] | No common workshop solvent; 1,2-dichloroethane destroys it inside a week and dichloromethane — a carcinogen — dissolves the surface.[24][25] |
| Softened or crazed by | Acetone and ethyl acetate plasticise the matrix rather than dissolving it; water attacks the exposed iron.[23][1] | Acetone (+16 % weight over 1 year at 23 °C), ethyl acetate, toluene and DMF swell and soften it; methanol crazes it.[24] |
| Solvent welding & smoothing agent | None — PLA has no workshop-safe solvent, and the iron loading blocks the surface flow smoothing needs.[23] | Dichloromethane brushed on is the only agent that smooths PETG — a controlled carcinogen, not workshop stock.[25] |
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
- Magnetic Iron PLA — product page and technical data Proto-pasta · 2026-08 · tds
- Prusament PETG Recycled Technical Datasheet Prusa Polymers · 2026-08 · tds
- Spectrum r-PETG Technical Data Sheet Spectrum Filaments · 2026-08 · tds
- Fiberon PETG-rCF08 Technical Data Sheet V1.0 Polymaker · 2026-08 · tds
- Proto-pasta product catalogue Proto-pasta · 2026-08 · vendor
- 3DXTech product catalogue 3DXTech · 2026-08 · vendor
- GreenGate3D Recycled PET-G — product data GreenGate3D · 2026-08 · vendor
- Polymaker product catalogue Polymaker · 2026-08 · vendor
- Filament PM RePETG technical data sheet Filament PM (Plasty Mladec) · 2026-08 · tds
- Prusament PETG Technical Datasheet v1.1 Prusa Polymers · 2022-02 · tds
- PETG — material basics Polymaker Wiki · 2026-08 · doc
- Composite materials with metal or wood particles Prusa Knowledge Base · 2026-08 · doc
- PET and PETG — Ultimate 3D Printing Materials Guide Simplify3D · 2026-08 · doc
- Filament Material Guide Prusa Knowledge Base · 2026-08 · doc
- Wet Filament — signs, causes and drying Polymaker Wiki · 2026-08 · doc
- PCTG vs PETG comparison — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
- Extrudr PETG vs PCTG vs XPETG-CF — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
- Prusament PETG-CF vs PETG V0 vs PETG — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
- BambuLab PETG Basic vs Translucent vs PETG-CF — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
- Mechanical Properties of Additively Manufactured Polymeric Materials — PLA and PETG — For Biomechanical Applications Polymers 16(13):1868 · 2024-06 · paper
- Prusament PETG V0 Technical Datasheet Prusa Polymers · 2026-08 · tds
- 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
- Solubility Study of Ingeo Biopolymer Grades in Common Organic Solvents (NWPD003) NatureWorks · 2019-10 · tds
- Eastman Spectar copolyester — Chemical resistance (unstressed bars, 1 year at 23 °C) Eastman Chemical Company · 2026-08 · tds
- Improve your 3D prints with chemical smoothing Prusa Research · 2026-08 · doc