PETG prints best with a nozzle temperature of 230–250°C, a bed temperature of 70–85°C, and moderate print speeds. It’s stronger and more heat-resistant than PLA, but it requires a few specific settings adjustments to avoid the stringing, poor adhesion, and surface defects that frustrate most beginners. Here’s what you need to get clean, reliable PETG prints.
Temperature Settings
PETG has a working temperature range of 220–260°C at the nozzle, but most brands print well between 230 and 250°C. A good starting point is 240°C for the first layer, then 235–245°C for the rest of the print. If you’re after maximum layer strength (for functional parts, enclosures, or anything that needs to handle stress), push closer to 255°C. For the best surface finish, stay toward the lower end of your filament’s range.
Set your bed temperature between 70 and 85°C. Glass beds generally need the higher end of that range for reliable adhesion, while textured PEI sheets work well around 70–75°C. Some slicer profiles default as low as 50°C, but bumping up to at least 70°C makes a noticeable difference in first-layer reliability.
Choosing the Right Build Surface
PETG bonds aggressively to smooth PEI sheets. So aggressively, in fact, that it can rip chunks out of the surface when you try to remove a print. If you’re using a smooth PEI plate, you need a release agent between the filament and the surface. The most popular options are a thin layer of glue stick, a light coat of hairspray, or even a dusting of baby powder for prints with large flat bottoms. Some users dissolve glue stick in water, filter out the waxy residue, and apply the solution with a microfiber cloth or spray bottle for a thinner, more even coating. A spray of glass cleaner (like Windex) also works as a release agent on smooth PEI and is easy to reapply between prints.
Textured PEI sheets are the easier option for PETG. The texture gives enough grip for adhesion during printing but releases cleanly once the plate cools. If you’re printing PETG regularly, a textured sheet saves a lot of hassle. For textured or specialty plates where you still want a release agent, hairspray preserves the surface texture transfer better than glue stick.
Print Speed
PETG is less forgiving than PLA when it comes to speed. Print too fast and you’ll see poor layer adhesion, extruder skipping, and rough surfaces. Print too slow and the extra heat exposure causes oozing, stringing, and warped features. For standard PETG filament, 30–50 mm/s is a reliable range. If you’re dialing in a new filament, start around 15 mm/s and work upward until you find the sweet spot for your printer.
Some specialty high-speed PETG filaments (like Bambu Lab’s translucent PETG) are formulated to handle speeds up to 200 mm/s, but don’t assume regular PETG can do the same. Standard formulations fall apart at those speeds. One setting that should always be fast: travel moves. Set these to at least 120 mm/s so the nozzle spends as little time as possible moving between print areas, which reduces oozing and stringing.
Retraction Settings to Reduce Stringing
Stringing is the most common complaint with PETG, and retraction settings are your main tool for fighting it. The right values depend on your extruder type:
- Direct drive extruders: 0.5–2 mm retraction distance
- Bowden extruders: 3–6 mm retraction distance
Going beyond these ranges often causes jams rather than reducing stringing. For retraction speed, 20–45 mm/s works well. Too fast and the gears grind the filament; too slow and the molten material has time to ooze before the retraction takes effect. If you’re still seeing fine hairs between features after tuning retraction, try lowering your nozzle temperature by 5°C increments. PETG stringing is almost always a temperature or retraction problem, not a speed problem.
Part Cooling Fan Settings
PETG needs less cooling than PLA. Too much fan and you weaken the bond between layers, which defeats one of PETG’s main advantages (its strength). Too little fan and overhangs droop and fine details lose definition. A fan speed of 30–50% is a common starting point. Turn the fan off entirely for the first few layers to ensure strong bed adhesion, then ramp it up gradually. For purely functional parts where appearance doesn’t matter, you can run with minimal or no cooling to maximize layer bond strength.
Hotend Compatibility
You don’t need an all-metal hotend for PETG. Standard PTFE-lined hotends work fine as long as you stay below 250°C, which covers most PETG printing. Higher-temperature PTFE tubes (like Capricorn brand) extend that safe range to around 260°C. If you’re already printing PLA on a budget printer, you can almost certainly print PETG without any hardware changes. An all-metal heat break is a worthwhile $10 upgrade if you plan to regularly push temperatures above 250°C for maximum strength prints.
Keeping Filament Dry
PETG absorbs moisture from the air, and wet filament causes bubbling, popping sounds during extrusion, rough surface texture, and excessive stringing. If your spool has been sitting out for a few weeks, dry it before printing at 60–65°C for 4–6 hours in a filament dryer or a conventional oven set to its lowest temperature. Don’t exceed 70°C or the filament can start to soften and fuse on the spool. Polymaker recommends a more aggressive 70°C for 8 hours for their PETG, so check your specific brand’s data sheet if available.
For long-term storage, keep spools in sealed bags or containers with desiccant packets. A dry box that feeds filament directly to the printer is the gold standard if you live in a humid climate.
Ventilation During Printing
PETG produces lower emissions than ABS, but it’s not emission-free. Lab testing has detected small amounts of toluene, xylene, ethylbenzene, and formaldehyde during PETG printing. At 250°C and above, benzene also appears. Total volatile organic compound concentrations measured in one study were around 550 parts per billion at the source, which translates to roughly 16 ppb in a typical room. These are low concentrations, but the recommendation from researchers is straightforward: print in a space where people aren’t sitting for extended periods, and ventilate the room. An enclosed printer with a basic carbon filter, or simply running the printer in a room with an open window, covers most home setups.
Removing Prints From the Bed
Let the bed cool completely before trying to remove a PETG print. On textured PEI, most prints pop off on their own once the plate reaches room temperature. On smooth surfaces, a plastic scraper is the safest removal tool since metal scrapers can gouge PEI coatings.
For stubborn prints, drip isopropyl alcohol around the edges and wait a few minutes. It wicks underneath and loosens the bond without requiring force. Alternatively, put the entire build plate in the freezer for 15–20 minutes. The temperature difference causes the print to contract and release. If PETG residue is left behind on the plate, print a large flat layer of the same filament directly over the residue, let it cool, and peel everything off in one piece. This trick works surprisingly well and avoids scraping damage to the build surface.