The wave pattern you're experiencing on some parts of your printed model could be caused by several factors. Here are some troubleshooting steps you can try:
Check your printer settings: Ensure that your printer is properly calibrated, especially the bed leveling. Incorrect bed leveling can result in uneven layers and cause wave-like patterns.
Print temperature: PETG filament requires a specific temperature range for optimal printing. Make sure you are using the correct temperature recommended by the filament manufacturer. Fine-tuning the temperature might also help reduce the wavy patterns.
Cooling: Insufficient cooling can cause overheating and lead to warping or other distortions. Check your part cooling fan to ensure it is functioning properly during the print.
Print speed: If you are printing too fast, it can affect the quality of the print. Try reducing the print speed to see if it helps eliminate the wave patterns.
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