[Sonic 4K] Replacing the FEP Film

Replacing the FEP film or PFA (nFEP) film is an essential maintenance task for resin 3D printers. It needs to be changed if it becomes dented, deformed, or pierced, but minor scratches and smudges on the film usually don't require replacement as they don't affect print quality.

If you need to replace a new FEP film, follow these steps:

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

Disassembling the Resin Vat

1. Take the vat and clean it thoroughly with the sanitizing alcohol, then use a soft paper towel to wipe it and let it dry
2. Place the resin vat in an upside-down position and loosen the 14 screws from the vat using a 2.5mm wrench

3. Remove the metal frame from the resin vat using a wrench

4. Remove the old FEP film.
5. Clean the vat and frame 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 how to Remove Stripped Screws

Adding New FEP Film and Reassembling the Resin Vat

1. Apply the new FEP film to the bottom of the resin vat
2. Then place the metal frame on top of the FEP film
3. Hold it in place and once the holes and everything else are properly lined up
4. Poke holes in the FEP film with a sharp-pointed item like a wrench
5. Tighten the 4 screws located at the corners, alternating between opposite corners to ensure even tension

6. Tighten the 6 screws located in the middle of each side, alternating between opposite screws.

7. Tighten the remaining screws alternatively 

8. Using a box cutter, trim the excess FEP film as close to the vat as possible, ensuring that nothing protrudes
9. Finished