After a couple of failed prints from files that had already worked before, I knew the culprit: a worn, cloudy FEP film. In May 2021 I showed how I replaced it on my NOVA3D Elfin2 Mono SE.
When to change the FEP
My FEP looked fuzzy, dark and damaged after all my prints. The giveaway was failed prints from files that were already sliced and had printed correctly before. When I emptied the vat I found hardened resin stuck on the bottom, and some areas were damaged so badly that the UV light from the LCD wouldn't pass through properly. It was impossible to clean, so it needed replacing.
Step by step
- Put on gloves and a mask. I once thought it wouldn't be a problem, breathed in a lot of resin fumes, and it was not nice.
- Remove the failed print and set it aside.
- Empty the vat, filtering the resin into a container so you can reuse it.
- Wipe off the remaining resin with paper towels.
- Take the vat to your desk and unscrew the 12 screws holding the FEP frame.
- Remove the old film and clean the frame with a bit of isopropyl alcohol, since resin and dirt collect in between.
- Fit the new NOVA3D FEP, pressing the screws through so it sits in place.
- Tighten all the screws firmly. The film has to be under tension to stay flat and work properly.
- Clean the new FEP inside and out to remove fingerprints.
- Clean the LCD screen with isopropyl alcohol too.
- Put the vat back, screw it in, pour the resin and run a test print.
I had put this off for a couple of weeks, trying and trying again. But once the FEP reaches its limit, it's better to just change it.