Why do good prints go bad?


I’ve been using the Moai for about a year now.
When it works, it’s fantastic! Amazing details.
Unfortunately the thing is very temperamental!
1 of every 3 prints fails. I’m getting a cured blob of hard plastic on the fep vat film and a thin smear on the build plate. I clean the Vat and plate and run the very same print at the very same settings under the very same conditions in the very same position and it works.
Really? Am I the only one?

I agree. There seems to be no explaining some of the failures. Very aggravating.

one thing to note is that printing 1 model on the same area over and over would degrade the FEP film faster
has it been like this since the starts? have you ever re-place the FEP film or run a check up once in a while?

Yes I know that about printing in the same spot clouds up the film in the fep vat.
What I described happens even with a brand new vat…with brand new film…even with the pdms vat. Failure…no changes…success!

try to increase the z reset position by 1 or 2, see if that make any changes in the success rate
I’m suspecting the new vat you are having require re-leveling

Thanks for your response!
I had 4 successful prints with the new vat film, the new laser, and a new data card…but I didn’t level the build plate.Then 2 failures. I leveled the build plate. Failure. I raised the z reset by 1. Failure. How do you check the card reader?

how is the re-level results ( ABCD)
you know the card reader fails when it won’t show the directory files, and fails to prints files that are used to print fine even though you have re-format the SD card or change cards multiple times

Ok…so I ordered a new card reader, 4 weeks later…got it today. I bought a new laser, new film, leveled the build plate, new resign, SD card. Even bought one of your heaters. Still…the vat doesn’t peel from the build plate. I sat there and watched the level count go up…but the vat does not move. Just a chunk of cured resin on the vat film.
Any more suggestions?

is the vat tilts when you boot up your Moai?
if not, please check your PM motor, if it’s broken i’m afraid you would have to purchase a new one as well

The vat tilts when I boot up

It doesn’t tilt when the part is printing.
Could it be a setting?
Thanks.

20200516_063013_HDR-1 20200516_063029_HDR-1

These are the settings I’ve been using

One thing I forgot to tell you! Back in January I accidentally dripped some resin down onto the acrylic plate guarding the mirrors in the galvo assembly. I replaced the acrylic play with a same sized piece of plastic I cut out of the plastic that comes in a picture frame. It worked okay. Could the laser have degraded that piece of plastic over time? A little resin dripped down around the mirrors, but I’ve had successful prints anyway.
Your advice is greatly appreciated… I still love this Moai! LOL

@markmarinelli is the tilting also not happen when you try with the pre-sliced gcodes?
if so, try to re-flash the firmware using this guide : https://peopoly.dozuki.com/Guide/Moai+-+Firmware+Upgrade/3

no, the sole purpose of the acrylic is to protect the galvo from resin drops, nothing special about how it’s made

Whoa! those settings did it! thank you
although Im using z reset 1817 instead of 1877…

Thanks!!

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the settings on the guide i sent was for PDMS, 1817 is for FEP, nothing to worry about

So I’m using the firmware settings you suggested and got 5 perfect prints. Then one like this picture…the first layer of the models platform is ripped away from the supports on the C/D side of the plate. I re leveled it and got more prints with the same problem
Should I lower the PM motor speed setting?

Lower it to 10 and increase the support tip size, that will do the trick

I lowered the PM motor to 10 and increased support tips to 1.25 and it’s still happening.

Why does the vat get stuck while the PM motor is tipping it, then spring loose and there’s a loud clunking sound? It’s happening when the deformed area is being printed?

Let’s go back to the basics
the loud clicking noise is the peeling sound, from the shape of the model it’s easy to understand why
you will notice from your orientation there’s a sudden change in surface area from support to model’s base.
I recommend to hollow the model in Asura, place a few 3mm vent holes and orient your model. Use inner support as well