How to replace the FEP on an Elegoo Mars /2/Pro

I’ve seen a few threads posted on various places about confusion with replacing a FEP on an Elegoo printer so thought I’d do a post showing how to do. It’s really very very easy, nothing to worry about and takes about twenty minutes. Just take your time and follow these easy steps.

Firstly you need a few things:

  • New FEP, I use these Fep sheets from Amazon. On a Mars 2 and pro you need the 200mm x 140mm size.
  • Two Allen (hex) keys sized:
  • A deck of playing cards (25 cards I used, about 8mm worth in height when stacked).
  • A sharp knife.
  • A sharp pointed tool, I use a pick but a toothpick should do.
  • Kitchen towel to sit the reservoir tank on.

So start off by removing the tank from the printer. Clean any excess resin out with alcohol and kitchen towel, obviously wearing gloves. Remove the old FEP by unscrewing the screws on the underside of the tank, when the FEP holder is free, remove all the other screws so the two parts of the frame release the old FEP sheet. Clean up all the parts and get ready to fit the new FEP.

Firstly put down some kitchen towel to have a clean space and protect the FEP. Place the bottom piece of the frame on the towel and then put 24 stacked playing cards in the centre. Rest the new FEP sheet on the frame, centralise it as best you can, there will be a cm or so excess all around. That’s fine. Lay the second part of the frame on top of the FEP and line it up with the bottom part.

Press down on the frame, the FEP will have some slack due to the playing cards, this is fine. Whilst holding down the frame firmly, pierce the corner small screw hole. Push a screw down into it and screw down firmly but not mega tight.

Now do the other three corners. Then start doing the extra screws. Do them in an opposing fashion. Once they’re all in do them up tight.

Remove the playing cards, pop the frame over the bottom of the tank and push the frame into the tank. You may struggle as the excess FEP will get in the way. Push it down into the bottom of the reservoir, pierce the corner screwhole in the FEP and screw down one of the larger screws.

Once again, do the rest in an opposing fashion. When they’re all in, do them up tight.

Now the FEP is fitted it should be almost like a drum skin, and twang when you tap it. Now cut the excess off the FEP by running a new sharp blade around the inner edge of the reservoir.

Job done!