[Sonic Mini 8K] Replacing the FEP Film

Replacing the FEP film or PFA (nFEP) film is an essential maintenance task for resin 3D printers. Minor scratches and smudges on the release film usually don't require replacement as they don't affect print quality. However, a replacement is necessary if it has become dented, deformed, or pierced.

If you need to replace a new FEP film, just follow the instructions in this article.

The FEP film needs to be replaced periodically. Learn more about when to replace it here.

1. Disassembling the Resin Vat

• Remove the resin vat from the printer 
• Clean the entire resin vat thoroughly with 95% sanitizing alcohol
• Use a soft paper towel to wipe the resin vat and let it dry
• Place the resin vat in an upside-down position 
• Use the 3 mm wrench to loosen the 4 corner screws 
• Use the 2.5 mm wrench to loosen the remaining screws on the bottom of the vat
• Use a wrench to pry the metal frame and remove it from the resin vat
• Flip the metal frame over 
• Use a 2mm wrench to remove all screws on the metal frame
• Remove the old FEP film
• Clean the vat and frame with 95% sanitizing alcohol to remove any residual resin

To loosen stubborn screws, apply alcohol to the screw joints and let them sit for about 15 minutes before attempting to loosen them again. For details, please refer to article here.

2. Placing the New FEP Film

• Remove the protective film from the new FEP film before installing it onto the frame
• Sandwich the new FEP film between the two metal frames (please refer to the video)
• Hold the FEP film in place and ensure the holes and everything else is properly lined up 
• Poke holes in the FEP film with a sharp-pointed item like wrench
• Tighten the 8 screws located at the corners, alternating between opposite corners to ensure even tension

• Tighten the 4 screws located in the middle of each side, alternating between opposite screws.

• Tighten the remaining screws alternatively

3. Reassembling the Resin Vat

• Place the newly installed FEP film frame back into the resin vat (the holes with the bevels should be pointed up)
• Tighten the 4 screws located at the four corners of the frame diagonally

• Tighten the 8 screws located in the middle of each side diagonally

• Tighten the remaining 2.5mm screws

• Using a box cutter, trim the excess FEP film as close to the vat as possible, ensuring that nothing protrudes
• Done!