How to print with PETG Filament?

PETG is the material that fills the gap between easy-printing PLA and engineering-grade ABS. It offers significantly better impact resistance and temperature tolerance than PLA, with far less warping and printing difficulty than ABS. For functional parts, kitchen accessories, chemical-resistant components, and anything that needs to outlast PLA, PETG is the first choice.

Key Properties

Heat deflection temperature	62°C
Tensile strength	40–50 MPa
Density	1.27 g/cm³
Shrinkage	Virtually zero
Food contact safe	Yes
Chemical resistance	Excellent (oils, cleaning agents, mild solvents)
UV resistance	Moderate (UV Resistant variant: certified excellent)
Moisture sensitivity	High — dry before use
Diameter tolerance	±0.05 mm

Recommended Print Settings

Nozzle temperature	230–245°C
Bed temperature	70–90°C
Print speed (standard printers)	20–80 mm/s
Print speed (Bambu Lab / high speed)	Up to 150–200 mm/s with tuned profiles
Cooling fan	50–70% (lower than PLA)
Enclosure	Not required, helpful for large parts
Diameter tolerance	±0.05 mm

Drying PETG Before Printing

PETG is highly hygroscopic — it absorbs moisture from the air faster than PLA, and printing with wet PETG causes stringing, surface rough texture, popping during extrusion, and poor layer bonding. This is the single most common cause of poor PETG results.

• Dry at 65–70°C for 4–6 hours before printing if exposed to air for more than a few days
• Store in sealed containers or resealable bags with silica gel desiccant
• A filament dry box feeding directly to the printer is ideal for PETG in humid climates

Bed Adhesion

PETG adheres strongly — sometimes too strongly. The key is preventing it from bonding permanently to your bed surface.

• PEI sheets: Apply a very thin layer of glue stick or hairspray before printing. Bare PEI at high bed temperatures can bond so permanently to PETG that the print tears the PEI surface on removal. Never print PETG directly on bare PEI above 80°C without a release layer.
• Glass: Apply a thin layer of glue stick. Works reliably and gives a smooth first layer.
• Textured PEI: Generally safe for PETG without a release agent at 70–75°C — the texture provides adhesion without flat-surface bonding risk. Check your printer's recommendation.

Printing Transparent and Clear PETG

PETG is naturally near-transparent in its base form — ideal for light diffusers, display cases, and backlit components. To maximise clarity:

• Use a higher nozzle temperature (240–245°C) for better layer fusion
• Reduce cooling fan to 20–40% to allow layers to meld fully
• Increase infill overlap percentage to reduce internal voids
• Print slowly (20–40 mm/s) for maximum transparency
• Dry the filament thoroughly — moisture causes milky cloudiness in clear PETG

Common Issues and Fixes

Stringing

PETG strings more than PLA. Dry the filament first — most stringing is caused by moisture. Then increase retraction distance (4–6mm for Bowden, 1.5–3mm for direct drive) and speed, reduce travel speed, and try enabling combing mode. A temperature tower helps find the sweet spot where stringing minimises without sacrificing layer adhesion.

Layer Adhesion Problems

Increase nozzle temperature by 5°C and reduce cooling fan speed. PETG needs more heat and less cooling than PLA for strong inter-layer bonding. This is the most common trade-off — more cooling gives better overhangs; less cooling gives stronger layers.

Bed Adhesion Too Strong (Print Won't Release)

Let the bed cool fully to room temperature before attempting removal. If using PEI, add a glue stick release layer next time. Never force a PETG print off a hot PEI bed.

Rough Surface Texture or Popping Sounds

This is wet filament. Dry at 65–70°C for 4–6 hours and retry.

Post-Processing PETG

• Sanding: PETG sands well from 200 grit upward. Wet sanding gives the best surface finish.
• Painting: Accepts acrylic and enamel paints with a plastic primer. No vapour smoothing (unlike ABS).
• Gluing: Cyanoacrylate (super glue), epoxy, and IPA-based adhesives all work well. Ensure surfaces are clean and lightly sanded.
• Drilling and tapping: PETG machines cleanly. Drill slowly at low speed to avoid melting.

Food Safety

Eolas Prints PETG is food contact safe. For food-contact applications, note that layer lines in FDM prints create microscopic crevices where bacteria can accumulate. For items that will be washed repeatedly or used with food, print with tighter layers, use a food-safe coating, or choose solid infill. Our PETG UV Resistant variant is also food contact certified.

Eolas Prints PETG Range

• PETG Filament — standard grade, food safe, virtually zero shrinkage. Available in 1.75mm and 2.85mm in multiple colours.
• PETG UV Resistant — certified UV stable for outdoor applications. Maintains colour and structural integrity after extended sun exposure. Food safe.
• PETG Transition — gradient colour, UV resistant, made sustainably from manufacturing offcuts. Ideal for outdoor decorative parts.