One common issue that users encounter with PETG filament is stringing or “easy drawing,” where thin strands of filament form between different parts of the print. Stringing can ruin the appearance of prints, especially on complex models. Fortunately, there are several effective ways to reduce or eliminate this issue.
- Optimize Retraction Settings
One of the primary causes of stringing is inadequate retraction settings. Retraction refers to the process where the filament is pulled back into the nozzle during non-extrusion moves to prevent unwanted filament leakage. Adjusting the retraction settings can significantly reduce stringing with PETG.
Retraction Distance: Increase the retraction distance slightly, typically between 5mm to 7mm for direct drive extruders and up to 10mm for Bowden setups.
Retraction Speed: Increase the retraction speed to quickly pull the filament back, usually around 30-50mm/s, depending on your printer’s capabilities. However, avoid setting it too high to prevent clogs.
2. Lower Printing Temperature
PETG has a relatively high printing temperature range (230-250°C), but higher temperatures can cause the filament to remain molten for longer periods, leading to stringing. Try lowering the printing temperature in small increments (5°C at a time) until you find a balance where the filament flows smoothly without causing stringing. Many users find that temperatures around 240°C work well for reducing stringing with PETG.
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Adjust Travel Speed
During non-printing moves, increasing the travel speed can help prevent stringing. A faster travel speed, such as 150mm/s or more, minimizes the time the nozzle spends moving between parts, reducing the chances of oozing filament and string formation. -
Use a Cooling Fan
Effective cooling helps solidify PETG quickly, reducing the chances of stringing. Make sure your printer’s cooling fan is set to run at an optimal speed (about 50-70%) after the first few layers to prevent excessive filament drooping or stringing.
Stringing with PETG filament can be frustrating, but by optimizing your retraction settings, adjusting the print temperature, increasing travel speed, and ensuring proper cooling, you can significantly reduce or eliminate the issue. These adjustments will improve the quality of your prints, resulting in smoother and more accurate models.