3D Printing Info

Filament comparison

PLA Stone vs TPU-CF

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

Stone-filled PLA guideCarbon-fibre TPU guide

2 selected · all documented properties

Open these two in the interactive comparisonMore PLA Stone comparisonsMore TPU-CF comparisons
PLA Stone vs TPU-CF — documented properties and sources
PropertyStone-filled PLAPLACarbon-fibre TPUFLEX
Market snapshot
Listing priceUSD/kg; dated snapshots$22.99/kg median; $15.99–$49.16/kg across 6 dated product listings$107.05/kg median; $107.05–$107.05/kg across 1 dated product listings
Identity & Market
Base polymer / chemistryPLA filled with stone or mineral powder — Formfutura StoneFil declares 40–50 wt% stone powder[1][2]Carbon-fibre reinforced thermoplastic polyurethane at the hard end of the range[3]
Densityg/cm³1.22 (Bambu Lab PLA Marble) and 1.50–1.70 (Formfutura StoneFil), ISO 1183[2][1]1.22 (Extrudr FLEX HARD CF, ISO 2781)[3]
Typical priceUSD/kg1 kg spools cluster near 21[4][5]107 for the only retail listing found (Extrudr 0.5 kg coil, incl. VAT)[6]
Price range across brandsUSD/kg16–49 across brands; SUNLU 16, ELEGOO 19, Polymaker 21, Bambu Lab 25, Prusament 38, Filament PM MarbleJet 49 on 0.5 kg spools[7][5][4][8][9][10]One listing only: EUR 49.56 incl. VAT per 0.5 kg coil, direct from Extrudr; no reseller or second brand found[6]
Market availability1–5Stocked by most mainstream brands[4][5][7]Niche, a handful of specialist brands — Extrudr's FLEX HARD CF is the only carbon-filled flexible with a published datasheet found here[3]
Spool sizes & diameters1.75 and 2.85 mm; 0.5 and 1 kg spools plus refills[5][1]1.75 mm; 0.5 and 2 kg coils[6]
Typical applicationsArchitectural models, sculpture and props with a matte mineral surface[2]Stiffened flexible parts — damping mounts and semi-rigid brackets[3]
Printing Parameters
Nozzle temperature°C190–230 (Bambu Lab)[2]230–260 (Extrudr FLEX HARD CF)[3]
Bed temperature°C35–45 (Bambu Lab)[2]50–90 (Extrudr FLEX HARD CF)[3]
Enclosure / chamber requirement1–5Open frame is fine[2]Open frame is fine[3]
Part cooling fanFan on[2]Not documented
Bed surface & adhesion aidNot documentedPEI sheet or painter's tape; Polymaker warns TPU can over-stick and advises a glue stick as a release agent[11][12]
Maximum volumetric flow (mm³/s; see test conditions)mm³/sNot documented1.6–8 at the 20–100 mm/s Extrudr specifies on a 0.4 mm nozzle at 0.2 mm layer[3]
Overall printing difficulty1–5Easy — minor profile tuning; 0.2 mm nozzles are not usable[13]Advanced — enclosure, hardware upgrades, tuning; hardened nozzle needed[3]
Extruder requirementNozzles below 0.4 mm are not compatible (Bambu Lab)[13]Not documented
Hardware Wear & Reliability
Nozzle hardness required1–4Brass acceptable; hardened steel for volume work — Bambu Lab's compatibility table says no hardened nozzle is needed while the note under the same table groups PLA Marble with particle-filled materials that should always use one[13]Hardened steel required — Extrudr marks FLEX HARD CF as needing a hardened nozzle where its unfilled FLEX grades do not[3]
Abrasiveness1–5Moderately abrasive — stone fill[13][1]Highly abrasive — standard CF composite[3]
Nozzle clog risk1–5Moderate — needs dry filament and a clean nozzle[13]High — jams from moisture, heat creep or particles; a flexible base plus chopped carbon fibre, which Prusa lists as a higher nozzle-clogging risk, and Extrudr requires a hardened nozzle[14][3][11]
Hotend requirementNot documentedNo special hot-end required, but a direct-drive extruder is (Simplify3D)[11]
Moisture Behaviour
Moisture absorption (hygroscopicity)1–5Moderate — 0.44 % saturated at 25 °C / 55 % RH[2]Moderate[15]
Equilibrium moisture content at ~50 % RH%0.44 saturated at 25 °C / 55 % RH (Bambu Lab)[2]Not documented
Drying temperature & timeNot documented60 °C for 6 h (Extrudr FLEX HARD CF)[3]
Symptoms when wetNot documentedBubbling and popping at the nozzle, stringing and a rough surface[15]
Effect of moisture on strengthPolymaker rates PLA low-sensitivity and publishes no dry-versus-conditioned figures for this grade; absorbed water flashes to steam and shows as bubbling and poor layer adhesion[15]Polymaker groups TPU with the highly hygroscopic materials; no dry-versus-conditioned figures are published[15]
Storage requirementNot documentedSealed with desiccant; often kept in a dryer during the print[15]
Mechanical Properties
Tensile strength (XY)MPa33 ± 4 printed XY, ISO 527 (Bambu Lab)[2]Not documented
Young's modulusMPa2330 ± 240 printed XY, ISO 527 (Bambu Lab)[2]35 (Extrudr FLEX HARD CF, ISO 527-2/5A/500)[3]
Elongation at break%6.7 ± 0.5 printed XY, ISO 527 (Bambu Lab)[2]380 ultimate elongation (Extrudr FLEX HARD CF, ISO 527-2/5A/500), against 490 for the unfilled FLEX HARD[3]
Flexural strengthMPa75 ± 5 printed XY, ISO 178 (Bambu Lab)[2]Not documented
Flexural modulusMPa2920 ± 180 printed XY, ISO 178 (Bambu Lab)[2]Not documented
Charpy impact, notchedkJ/m²9.5 ± 2.6 printed XY, ISO 179, notched (Bambu Lab)[2]Not documented
Other impact dataCharpy unnotched 24.0 printed XY (Bambu Lab, ISO 179)[2]Not documented
Layer adhesion / Z tensileMPa30 ± 4 printed Z, ISO 527 (Bambu Lab)[2]Not documented
Brittleness1–5Brittle — snaps with little warning[2]Very ductile — bends far before failing[3]
Hardness (scale-specific)Shore A / Shore D / RockwellNot documented70 Shore D (Extrudr FLEX HARD CF, ISO 868), against 58 Shore D for the unfilled FLEX HARD[3]
Creep resistance / sustained load1–5Poor — no stone-filled creep test; plain printed PLA sagged from 12 to 16.2–21.8 mm over 5 days at 1.25 kg[16][17][18]Below average — no CF-grade creep test; the grade is 70 Shore D where a 95A TPU bar crept from 74.5 to 82.7 mm over 5 days at 1.25 kg[3][19]
Fatigue / repeated-flex resistance1–5Poor — no grade-specific S-N curve; plain printed PLA ran 38 000–49 000 cycles at 30 % of tensile strength and the mineral filler leaves a brittle compound[20][2]Good — 380 % ultimate elongation and a damping application set (Extrudr cites longboard wheels), below the unfilled grades[3]
Elasticity / flexibility1–5Rigid[2]Semi-flexible[3]
Z strength as % of XY%91 by tensile, 73 by flexural (printed, Bambu Lab)[2]Not documented
Wear resistance & frictionNot documentedAbrasion 26 mm³ (Extrudr FLEX HARD CF, ISO 4649-A) — the same as the unfilled FLEX HARD[3]
Thermal Properties
HDT at 0.45 MPa°C56 (ISO 75, 0.45 MPa)[2]Not documented
HDT at 1.8 MPa°C53 (ISO 75, 1.8 MPa)[2]Not documented
Glass transition (Tg)°C56 (DSC)[2]-24 (Extrudr FLEX HARD CF)[3]
Melting point / Vicat°C156 peak melt (DSC); Formfutura gives a 120–170 melting range for StoneFil[2][1]Vicat A 140 (Extrudr FLEX HARD CF, ISO 306)[3]
Environment & Chemical
UV resistance1–5Degrades within weeks outdoors[21]Good — years with some colour shift; Polymaker lists UV exposure among the conditions TPU withstands[12]
Chemical resistanceNot documentedWithstands industrial solvents and UV exposure (Polymaker)[12]
Food contactNot documentedNot food safe without specific certification (Polymaker)[12]
Biodegradability / compostabilityNot documentedNot biodegradable[12]
RecyclabilityNot documentedNot accepted in household plastic collection[12]
Health & Safety
Fume toxicity1–5Low hazard — minimal VOC and particle emission[22]Low hazard — minimal VOC and particle emission; TPU was not among the nine filaments in the chamber study[22]
Ventilation / filtration requirement1–5None needed in a normal room[22]Open a window / occasional ventilation[22]
Dust & fibre handling hazardFormfutura's SDS sets an occupational limit of 1 mg/m³ for the stone powder and lists it as both a fibre and a particulate — do not dry-sand without extraction[1]Carbon fibre is bound in the matrix; sanding dust should not be inhaled[3]
Post-Processing
Sanding & machiningSands to a stone-like matte surface[1]Difficult to sand or smooth; Polymaker limits post-processing to trimming or tumbling[12]
Gluing & solvent weldingNot documentedCyanoacrylate bonds TPU; no common solvent welds it[12]
Vapour / chemical smoothingNot documentedNo practical vapour smoothing[12]
Support material pairingSupport for PLA (Bambu Lab)[2]Polymaker warns TPU supports are often very difficult to remove[12]
Dimensional accuracy & detailMatte mineral surface hides layer lines; 55° overhangs and 30 mm bridges as for plain PLA[2]Tear strength 165 kN/m (Extrudr FLEX HARD CF, ISO 34-1B)[3]
Solvents & Solubility
Soluble inChloroform dissolves the PLA matrix (10 % w/v, 2–4 h at 23 °C) and leaves the filler as loose sludge; laboratory reagent.[23]DMF, DMSO, NMP and THF dissolve the TPU matrix and leave the fibre; ketones are partial solvents. Laboratory reagents.[24]
Softened or crazed byAcetone, ethyl acetate and toluene plasticise the matrix but dissolve <1 % even at 65 °C; acetone submersion crazes parts.[23][25]Toluene and benzene swell it up to +50 % by weight at 23 °C; esters swell it severely; ethanol and IPA soften it.[24]
Solvent welding & smoothing agentChloroform vapour attacks only the resin fraction, so the filler is left standing proud; no workshop-safe agent exists.[26][25]None practical — the true solvents (DMF, THF, NMP) are laboratory reagents and leave the joint swollen and weak.[24]

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. StoneFil safety data sheet Formfutura · 2026-08 · msds
  2. Bambu Filament Technical Data Sheet — PLA Marble Bambu Lab · 2026-08 · tds
  3. Extrudr Product Catalogue (DURAPRO PA12 data block) Extrudr · 2025-03 · tds
  4. PLA Marble — product page Bambu Lab US Store · 2026-08 · vendor
  5. Polymaker product catalogue Polymaker · 2026-08 · vendor
  6. Extrudr TPU FLEX Hard CF — product page (1.75 mm, 0.5 and 2 kg coils, price) Extrudr (FD3D GmbH) · 2026-08 · vendor
  7. ELEGOO product catalogue ELEGOO · 2026-08 · vendor
  8. Printed Solid product catalogue Printed Solid · 2026-08 · vendor
  9. SUNLU High Speed PLA Marble 3D Printer Filament 1 kg SUNLU · 2026-08 · vendor
  10. Filament PM PLA MarbleJet technical data sheet Filament PM (Plasty Mladec) · 2026-08 · tds
  11. Flexible (TPE/TPU) — Ultimate 3D Printing Materials Guide Simplify3D · 2026-08 · doc
  12. TPU — material basics Polymaker Wiki · 2026-08 · doc
  13. PLA Usage Guide Bambu Lab Wiki · 2026-08 · doc
  14. Composite materials filled with carbon, kevlar or glass Prusa Knowledge Base · 2026-08 · doc
  15. Wet Filament — signs, causes and drying Polymaker Wiki · 2026-08 · doc
  16. BambuLab PLA Basic vs PLA Tough vs PLA-CF — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  17. Polymaker PLA Pro vs PLA-CF — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  18. Carbon Fiber PLA vs META-PLA vs PLA+ vs PLA by Sunlu — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  19. BambuLab TPU 95A HF vs Qidi TPU 95A HF — results spreadsheet My Tech Fun (Igor Gaspar) · 2024-02 · test
  20. Mechanical Properties of Additively Manufactured Polymeric Materials — PLA and PETG — For Biomechanical Applications Polymers 16(13):1868 · 2024-06 · paper
  21. PLA — material guide Prusa Knowledge Base · 2026-08 · doc
  22. 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
  23. Solubility Study of Ingeo Biopolymer Grades in Common Organic Solvents (NWPD003) NatureWorks · 2019-10 · tds
  24. Elastollan — Chemical properties: swelling and chemical resistance BASF · 2026-08 · tds
  25. Improve your 3D prints with chemical smoothing Prusa Research · 2026-08 · doc
  26. 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