PLA vs PETG

PLA and PETG are the two most popular consumer filaments. Most projects come down to choosing between them.

Use PLA when

• The part is decorative, low-stress, or indoor.
• You want maximum surface finish quality.
• You print on an open-frame printer in a cool room.
• You need a sharp first-layer trace (PLA's lower printing temp gives it crisper detail).

Use PETG when

• The part will sit outside or in a sunny window.
• The part will see mechanical stress (snap fits, brackets, hooks).
• The part needs to be food-contact-adjacent (PETG bottles, etc.) — PETG is generally considered safer than PLA for this, though neither is FDA-certified once printed.
• You need a part that can deform slightly without snapping.

Where PETG wins

• Toughness: PLA shatters; PETG bends.
• Heat resistance: PETG softens around 80°C vs PLA's 60°C.
• Layer adhesion: PETG bonds layers strongly, making it more reliable for thin-walled parts that experience torsional load.

Where PLA wins

• Speed: PLA prints faster on most consumer printers.
• Detail: sharper corners, cleaner overhangs without stringing.
• Bed adhesion: PLA sticks to almost anything. PETG can stick too well to PEI sheets and tear the surface — use a release agent or a textured plate.
• Cost: marginally cheaper per kg in most catalogs.

Stringing and oozing

PETG is notorious for stringing. The fixes:

1. Dry the filament — a wet PETG spool strings badly.
2. Lower the nozzle temperature 5–10°C from the recommended start.
3. Increase retraction distance and speed (only for direct-drive extruders).

Storage

Both filaments absorb moisture, but PETG is hygroscopic enough that even a week in open air degrades print quality. See storing filament.