How to pick a filament: PLA, PETG, ABS, ASA, TPU and PA-CF in practice
A short guide to the filaments I run daily on Bambu Lab, Prusa and other FDM machines — when to use what, what to avoid.
"Which spool should I buy?" is a question I get almost daily. Short answer: depends where the part ends up. Long answer is this article.
PLA — the default
Indoor parts, prototypes, decoration. Easy to print, dimensionally stable, low odour. Hates a car in the sun (softens around 55 °C) and UV. Ideal for open Bambu Lab A1 / A1 mini. Watch out for PLA-Silk — clogs nozzles more often.
Picks: Polymaker PolyTerra, Prusament PLA, Bambu PLA Basic / Matte. 0.4 nozzle, PEI sheet, 60 °C bed.
PETG — the workhorse
Tougher than PLA, OK outdoors, holds up to ~70 °C. Great for brackets, enclosures, kitchen helpers (food contact only with certified variants). Bonds aggressively to PEI — use a release layer.
Picks: Prusament PETG, Devil Design PETG. Glue stick or Magigoo PETG. On Bambu P1S/X1C raise cooling or thin details blob.
ABS / ASA — outdoor and thermally loaded parts
Need an enclosed chamber — without it expect warping and delamination. Bambu Lab P1S, X1C, Prusa CORE One and enclosed Voron are made for them. ASA beats ABS for UV; today it is the better outdoor choice.
Picks: Polymaker PolyLite ASA, Fiberlogy ABS+. Always ventilate.
TPU — flexible
Cases, gaskets, RC tyres. Shore 95A is universal, Shore 85A is genuinely soft and needs slow speeds. Skip TPU on Bowden setups.
PA-CF / PAHT-CF — functional parts
Carbon-filled polyamides are strong, heat-resistant and abrasive. Need a hardened nozzle, a hot chamber and dry filament. For automotive parts, jigs and machine components this is the go-to material on Bambu X1C and Prusa XL.
Money-saving rules
- Dry your filament — PETG, PA, TPU and ABS absorb moisture fast. A 80 EUR dryer pays for itself in a month.
- Cheap filament = more nozzle service. No-name PLA-CF will eat brass nozzles for breakfast.
- For Bambu AMS, avoid spools with uneven winding — "filament tangle" failures are more common on no-name brands.
Not sure what to buy for a specific part? Drop me a message — free guidance within 24 h.
Frequently asked questions
PLA, no question — ideally matte from Polymaker, Prusament or Bambu Lab. Easy to print, low odour, dimensionally stable. Avoid PLA-Silk and cheap no-name brands that clog nozzles.