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—use isopropyl alcohol for best results. Set your bed temperature between 70°C and 80°C to maintain good adhesion. Use a suitable build surface like a PEI sheet, glass with a glue stick, or blue painter’s tape for better grip. Applying a thin layer of glue stick or specialised adhesion spray can also help. Enable a brim or raft in your slicer settings to increase the surface area of the first layer, which reduces edge lifting. Print the first layer slowly, around 20-25 mm/s, and check that the nozzle height is calibrated correctly—too high and the filament won’t stick, too low and it could cause uneven extrusion. Finally, avoid drafts and sudden temperature changes by printing in an enclosed or semi-enclosed space. These steps will greatly reduce warping and improve your PETG print quality.