Prints are failing spectacularly!

[Legion]

Hello,
I purchased an Elegoo Mars P last year (august 2020) and since a couple of weeks I'm having problems:

instead of getting a print of the model I'm getting a chunky block of resin (see attached picture)

• The problem started slowly (once every 4/5 prints) but now is consistent and I can't get a nice print at all.
  
  
• I'm using the following resin: ELEGOO LCD UV 405nm Rapid 3D Resin for LCD 3D Printer 1000g Photopolymer Resin Grey. I've always used this resin so far, so I would exclude the resin.
  
  
• Also tested printing the same files I've been using so far and the problem is consistent, so I would exclude a problem with the slicer or the settings of the slicer.
  
  
• Also the printer is still in the same place and I could exclude changes in the lighting or the temperature of the room.
  
  

any suggestions?

The only possible things I could think of is that the LCD is malfunctioning

[cliffyk]

Do not use custom font colours on this forum. Those of us using the more conventional light colour scheme see your post like this:



At first it looked as though there was no message--then I realised what was going on and "highlighted" the text:



"last August" was 8 months ago, if you have printed for more than 250 to 350 hours (just 1.25 hours/day average) since then there's a 99.44% chance the LCD shutter is shot--that (250 to 350 hours) is how long they last (it's warranted for just 3 months).

Remove the resin vat and platen assembly, placer a sheet of printer paper on the lLCD and "print" this file (VatClean-00.stl. It is a full screen block that fully "illuminate" the LCD, if the LCD is bad you'll see dark blotches, streaks, etc. or just an overall too dark display.

like this:


a good LCD will display this:

[Legion]

Thanks, I'll give it a try

---

not sure if I did the test correctly, in my case I see the pattern with a bunch of squares which I guess are from the lamp undrneath the screen.
I used the "clean tank" option from the settings

   

[cliffyk]

It looks a bit dim overall. However if you have accomulated more than 250 to 300 hours of printing time it is shot--time for a replacement. Tou can trey increasing your exposure times by 25% to 30% to maybe buy some time--but you'l need a new LCD before too long. Elegoo should be more upfront about this in the owner's manual...