Burr, sag or something like that

[wolfloner]

Hi everyone,

I've a Mars C since an year ago, using Elegoo classic grey resin without problems.
But since a while, I don't know but all my prints have troubleshouting.
I'm printing very tiny items, 6mm to 20mm maximum, but mostly they are around 8mm.
I'm using Dotlbit FEP (0.015 to 0.02mm tick)
And I'm printing the whole tray almost each times.

Here my setting :




After a few layers, a kind of smudge sticks to the center of my print like a kind of skin. I thought of an agglomerate of flakes from unprinted media. I usually use 0.3mm supports. So I pump up them at 0.5mm even a while ago, I gone to 0.8.

what so ever the problem persists.



So I thought about the suction effect in the middle of the tank, I retensioned the FEP using the sponge method (https://www.youtube.com/watch?v=tsokPTRL...ooOfficial)
And today, It's even worse.
My print was good on a side of the tray not on the other where just half of the print was good. All the rest sticks to the tank bed.

Please do you have any ideas where can from my troubleshouting, it's already a month I broke my mind to know where are my mystakes and I start get crazy

Help !!!!
Thank you for the futures answers

[cliffyk]

it is most likely that the LCD shutter has gone bad--it is a "consumable" component (a "wear item") and typically wear out after 250 to 300 hours of printing. You can read more about how the shutter works and why they wear out in my post here.

If your printer is a year old and you have not yet replaced the LCD I guaranty that is the problem--in fact so does Elegoo, thay only warranty it for 3 months--from the owner's manual:

[wolfloner]

Thanks Cliffick,

You've right, I tested the screen with a basic rectangle to see the whole screen. The screen test from Elegoo isn't enough efficient. There are many black holes everywhere on it.
I ordered new one since, I must just install it now ^^

[cliffyk]

99.44% of he printing issues you described are LCD related--they wear out with disappointing frequency. Currently I have two "just-n-case" spares in stock.

In their defence, Elegoo has never promoted or claimed the built-in "Exposure Test" to be a "Screen Test"--that said I have never found any use for it at all--even as an "exposure test".

The owner's manuals I have seen have only provided a most cursory explanation of it's initialization and existence; and no real description of it's supposed utility...