Peeling stopped working on Moai 130

I have an issue I’ve not run into before. recently my Moai has stopped peeling.
the vat tilt system works and it runs a tilt at startup but my last 7-8 print attempts from Asura have failed (I assume) due to no/intermitent peeling.
I haven’t change any of my build/slice/print parameters.
I use model gray in a FEP vat.
I usually start a print and close the door so I didn’t notice the lack of peeling until recently.
At first I though it was a FEP issue so I changed the FEP film twice and no improvement. I switched to a new bottle of resin and no change. finally I noticed that the bed is not tilting after each layer.
I don’t know enough about gcode to look at the file and tell if there’s anything missing.

I format the card before every print.
I’ve been printing very successfully for over a year and suddenly this happens.
any ideas would be appreciated.

A little more info.
Peeling is definitely not happening anymore despite the bed tilting at startup.
I’ve considered that peel force with a load is preventing tilt motion but there’s no indication that it’s even trying to peel so I’m ruling out mechanical malfunction for now.
I need to try an old gcode file that used to work to see if it will peel. If it does then that should point to a flaw in the new gcode.
Again, same old copy of Asura with same old settings.
If signs point to gcode I’ll try reinstalling Asura and reslicing

This happened to others (me included: Why is the Vat not peeling?).
If you are lucky, that’s maybe just some bad contact (try unpluging and dismounting the pm motor, and put it back), if not…
You can also try to update/reinstall the firmware, as some pointed in that direction.

@Gimungus any updates after @totoreador suggestions?

Run it with no resin in the Vat. This may not be a GCode issue as vat tilt happens in the machine. You can insert gcode but if you haven’t changed it then it is most likely not the issue.

Check the cabling on the vat tilt motor, and check the bolt that attaches to the vat tilt frame. It might be falling to gravity, but the suction may be too much to allow it to fall through the same means. Make certain the bolt is taught, there might be some rotation.

If all of this is checks out, then I would want to examine your model orientation & suction.

I had a similar problem and the conclusion was, for me anyway, that the Asura software must have a bug somewhere that make it not write correctly to the SD card, and after a few tries it corrupts the SD. What i did was reformat the SD, fully, mot the quick format. Then I slice the file to my hard drive on the laptop. THEN insert the SD and drag to file to the SD and let the operating system to copy the file to the SD. I have not had the problem since, except when I forgot to look where the software was going to save the file and it went on the SD. After a few of these i had to format the SD again. All is fine now, i just do not install the SD into the laptop until the file is put on my desktop. This was i remember to have the OS copy the file and not let Asura do it.

An update.
I tried running the ring test file and it printed flawlessly.
I replaced Asura with same version but new copy.
Peeling is still intermittent to non existent with other files.
I opened the printer, tightened the set screw to the vat tilt mechanism (it wasn’t loose) but I loosened and retightened anyway.
Sometimes I get peels for about half the print the it stops
Sometimes it won’t peel at all
Suction is not likely the issue as the largest cross section of the file is no more than 60mm x 8mm.
Placement in vat seems to make no difference
Z-axis orientation makes no difference
One time it peeled consistently for around 800 layers then the peel motor started making clicking sounds like it was either slipping wasn’t strong enough to peel anymore. I pushed down on the vat, the print pulled loose from the FEP and peeling resumed…for a while before stopping again.
Most often it just doesn’t even try to peel.
I’ll try again with no resin.
I am using a 3rd party FEP material that I’ve had lots of success with for many months but just to rule that out I ordered some more from peopoly but it’s not here yet.
If it behaves with no resin I might assume the current FEP is too sticky.

Removed the vat and ran my print file for a few dozen layers. It “peeled” as normal. Replaced the vat and relieve led the build plate and ran the same file. No peeling now. I’d expect it should try and make some noise if it was trying to peel but couldn’t overcome peel forces. This wouldn’t be the issue. Print cross section is very small.
Set screw on peel motor is tight. Plug on peel motor is well seated and secure.
Really getting frustrated.

Wow, auto correct really messed up my last reply.

I removed the vat and ran a fresh file. All ran well and peeling was according regularly.
Replaced the vat and leveled the bed. I tried the same file but there was no peel happening once the vat and resin was replaced.
The motor did not even appear to be trying since it wasn’t making noise.
I have new Peopoly FEP arriving soon and I also ordered a replacement peel motor today in case the motor going bad or is to weak to pull against the FEP.
As I mentioned earlier that I tightened the set screw and checked the connection on the motor and they’re good.
I haven’t replaced the firmware yet but I think I’ll try that next while I’m waiting for parts to arrive.

Are you only slicing in Asura? I would jump straight to Cura and test a slice to see what happens. I know Asura can be buggy at times, but what slicer isn’t. I don’t think you need to replace the FEP anymore as it does not seem like your issue is with the film. Even if the film was going bad, the motor should attempt to tilt and wouldn’t click. Clicking while attempting to tilt might mean that there is something in the way, physically, stopping the tilt.
Run your test gcode with no resin and pull the power to your laser to watch the mechanations on the interior. It sounds like you tried to do all of this with resin in the vat. Unless you’re printing something that takes up more than 1/3 of the surface area of the printer you’re not going to experience peel forces that would stop the vat from tilting on a healthy tilt motor.
If your tilt motor is going bad, you can upgrade to the 1.20 firmware and start using Z Lift and disable it all together. That is a much better alternative for FEP film but not for PDMS.

My process is build in Maya, export .stl, cleanup/hollow (if needed) in meshmixer, add support/slice in Asura 2.24. This has worked great for me for the past year.
I have no experience with Cura.
I reloaded firmware v1.18, set Peopoly recommended settings from the wiki, re-leveled the bed again, created a new model/gcode file and printed.
This file has a significantly larger footprint than the previous one.
Peeling was working great at first. I left for a couple hours and when I checked again peeling had completely stopped. No motor sound, no movement of the vat at all. I let it go for another hour or so to see if it would start peeling again and it never did.
Peeling seems to be pretty random.
The clicking noise I mentioned earlier happens very infrequently but it is loud. I’d definitely sounds like the motor or shaft is slipping even though all screws are tight.
I have a new peel motor on order and will swap it out when it arrives.
One thing I haven’t mentioned yet is that prior to all this I had been printing some large footprint models. That’s when the motor noise first began. It was way more frequent then. I think I may have damaged the motor during that time.
I doubt there’s any physical blockage since the vat tilts cleanly on startup every time.
When I had the printer open earlier I also noticed that the motor cable has some resin residue on it. I’m thinking a drop must have spilled through the opening at the front of the vat while removing the build plate at some time. There was no sign of this residue on the plug however so I don’t think it could have gotten into the board or the connection. This may be nothing but I’m running out of ideas. Crossing my fingers I don’t have some crazy intermittent short on the board.

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Sorry for not seeing this before, I think the motor is the right way to go.
Its unlikely that the controller is bad, but just inspect it for resin as it can be conductive. Use a toothbrush with some IPA to clean it with no power.
I think you should go to 1.20 on the firmware and start using Z Lift. Which is Z Follows set to a negative number. I have mine set to 350 right now, which is if I remember correctly 3.5mm of travel. That vat tilt is perhaps the weakest link of the Moai, but is necessary on PDMS vats.

New motor arrived today. Pulled out the printer and replaced the motor as well as a general cleanup.
Re assembled everything, re-leveled the build plate and jumped right into the deep end with the file that’s been giving me so much trouble.
311 layers into a 1649 layer file and so far everything is working as it should.
Assuming this fixes things I’m not sure what’s up with the old motor. It was working intermittently. Maybe it was just worn out and not strong enough to pull with a load on it.
Not an electronics guy so I don’t even know how to go about looking into that.


20.5 hours later and my first successful print in over a month.
Looks like it was the motor. Running a second attempt at the same file. Looking good so far.