Overview
PETG (Polyethylene Terephthalate Glycol) combines the ease of printing of PLA with the strength and chemical resistance of ABS. It offers excellent layer bonding, low shrinkage, and is widely considered food-safe when printed on appropriate equipment.
PETG is an outstanding choice for functional mechanical parts, enclosures, and anything that needs to be tougher than PLA without the warping challenges of ABS.
Technical Properties
| Property | Value |
|---|---|
| Tensile Strength | 53MPa |
| Flexural Modulus | 2.1GPa |
| Heat Deflection Temp | 70–80°C |
| Layer Resolution | 0.1–0.3mm |
| Density | 1.27g/cm³ |
| Elongation at Break | 130% |
| Shrinkage | ~0.4% |
Advantages & Limitations
Advantages
- ✓Food-safe when printed on certified equipment
- ✓Excellent moisture and chemical resistance
- ✓High layer adhesion - parts are semi-translucent and visually attractive
- ✓Minimal warping - no enclosure required for most prints
- ✓Good impact toughness vs PLA
Limitations
- ✗Prone to stringing if retraction settings are not dialled in
- ✗Surface finish can show layer lines more visibly than ABS
Applications
Mechanical enclosuresWater bottles & food containersOutdoor fixturesMedical non-implant partsSnap-fit componentsPiping & fluid handling
Printing Tips
Print PETG at 230–250 °C with a bed temperature of 70–85 °C. Use a PEI sheet or light hairspray on glass. Slow down the first layer to 20 mm/s for best adhesion. Increase retraction distance slightly to reduce stringing.
Frequently Asked Questions
Is PETG stronger than PLA?
PETG is tougher than PLA - it has higher elongation at break (130% vs 6%) meaning it bends before it snaps. Tensile strength is similar, but PETG handles impact loads much better.
Can PETG be used outdoors?
Yes, PETG has reasonable UV resistance and is moisture-resistant, making it suitable for short-term outdoor use. For prolonged outdoor exposure, ASA is a better choice.