How to Prevent PETG Warping on the Print Bed

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

Answer: To prevent PETG from warping, start by ensuring your print bed is clean and free of grease or dust. Use isopropyl alcohol to wipe the surface. Set your bed temperature to around 70-80°C to improve adhesion. Applying a thin layer of a suitable adhesive like a glue stick or specialised print surface (e.g., PEI sheet) can help PETG stick better. Use a brim or raft in your slicer settings to increase the surface area of the first layer. Print the first layer slowly, at about 20-25 mm/s, and ensure it’s squished slightly onto the bed for good contact. Avoid cooling the print too quickly; keep the part cooling fan off or very low for the first few layers. Lastly, try to print in a draft-free environment or use an enclosure to maintain stable ambient temperature. These steps should significantly reduce warping and improve your PETG prints.