How to prevent PETG warping during 3D printing

Question: How do I stop PETG from warping off the bed?

Answer: To reduce PETG warping, start by ensuring your print bed is properly prepared. Use a clean, smooth surface like a glass bed or PEI sheet. Apply a thin layer of glue stick or use specialised adhesives designed for PETG to improve adhesion. Set your bed temperature to around 70-80°C to keep the first layers warm and minimise shrinkage. Print the first layer slower, around 20-25 mm/s, and increase the initial layer height slightly for better grip. If possible, print inside an enclosure or shield the printer from drafts to maintain a stable ambient temperature. Avoid excessive cooling on the first few layers; set your fan speed to 0-30% initially. Finally, consider using a brim or raft to increase the contact area with the bed, which helps hold the print down during cooling. Following these steps should significantly reduce warping and improve print success with PETG.