FEP Vat failure


Made it :slight_smile: Thanks for the tips, guys.

Beyond that, went back to my old VAT, it’s a bit cloudy, but the print is almost done and no signs of problems. I’m using exactly the same settings and temperature is the same print as it was with the new FEP VAT, about 30.5C. I’m posting the results when it finishes, with the settings (the print is really slow, I’ve lowered motor speed to 12 and reset went to 60).

I was thinking, maybe asura will create supports taking the new FEP VAT in consideration? Because I honestly don’t know what else to do.

Thanks again


Supports are finally there! But model is cuted into two halves… What is going on?! :frowning:


Check if the laser is blocked by a cable or similar - I can not think of any other possible reason.


One more try, one more failure. Tried Asura automatic supports.
Also, looked for debris in the VAT, was clean. Tension looks homogeneous. Waited 20 minutes with 30.3C - 30.6C to start printing. Resin was very “liquid”.

Any ideas of what could be wrong?


Room temperature: 30.6C (as picture attached)

Firmware version: 1.16

System Setting is default per Peopoly recommendation? (Yes/No) Yes

Build plate type: (Standard 1-piece / easy to level): easy to level

Vat: (Silicon vat / FEP vat) : FEP VAT

Cura Version and Profiles: 3.4.1, 40nm August profiles

Infill %: default (70%)

Laser Power: 54 (didn´t print the corner test until 54)

Z-reset position: 1816

PM Motor Speed: 12

Z Follow Speed: 10

What type Vat: (Peopoly Original vat, Recoated Peopoly vat, custom vat made by user): New FEP VAT

What type of resin: Hi-temp gray

Leveling measurement:

A, B, C, D (example 10.9mm) --> A (10.68) B (10.73) C (10.74) D (10.71)


have you increased pm reset?


Kept it in 40, I´ve heard I could move it to 80, but wasn´t sure about which would be the effect.


try with 60, also for that particular model you can probably use 0.06 layer height with no visible difference in quality


Thanks Matt, I´ll. Layer resolution affects the peelling forces?


well… less layers, less tilt actions :slight_smile: also it may help with that particular resin


Hi all,
Just wanted to pass on a couple tips for working with the FEP vat and large models, FWIW.

  1. Supports, if you think you have enough you don’t. This is from the print that works fine (size 100mmx75mmx30):

I have found that XYZNobel software works very well to create a forest of crosslinked supports.

  1. Positioning of the part correctly prior to support generation. Download PreForm from Formlabs and see how it will position the model. Replicate in your support maker of choice as closely as possible.

  2. Change the vat tilt settings to increase the tilt (40->60) and slow down (PM_moto=~10)

  3. Thicker FEP film (flexvat.com…just saying) is more forgiving, but the standard film works ok, but is more finicky. The Aluminum vat from Peopoly is pretty good, and changing film is a relatively quick task. I haven’t tried the Flexvat vat, but it is pretty similar from the looks of it.

  4. I can’t stay I have a quantitative reason why this works, but by observation, Rain-X (from a post in this forum) seems to decrease the release force (by sound…) when applied to the FEP film. The film is relatively hydrophobic, but with enough wiping around the Rain-x sticks.

I am running Cura 3.4.1, and either Peopoly standard resin (for testing) or Photocentic high tensile SLA resin (actual parts)

Also, the FEP vat smells way less.


Got a reply from @peopoly and did two tests with the ring gcode, the same settings I´ve used before, but increased PM reset to 80 and reduced PM Moto Speed to 10. With 51 laser power, the ring test print failed.
Raised laser power to 54 and got it right, but some holes didn´t open. Hard to grasp what´s going on, but I´m going to run another test with my model tomorrow. More supports, different orientation (head/ears down, one more drain hole), and 60nm resolution. Let´s see.

And I hope @peopoly can help, I´m not sure if I may have got another wierd hi-temp (gray) batch or I have something going on with my new FEP or maybe more hardware settings tweaking.

The next step would be using blue resin with the same settings and models. If it doesn´t work, I´ll go back to the old VATs and forget about New FEP VAT and hi-temp resing for good, I need to finish another prototype and my ecorche, which is almost ready for printing.




Did you mamage to print large scale models reliably and consistently?

I´ve done the same (reduced PM Moto to 10 and increased PM Reset to 80), but the only thing I can print is the ring test (using 54 laser power with hi-temp gray resin).


Hi Ricardo,
Yes, it seems to be consistent (on a not huge sample size of 4 identical big parts, and an assortment of little test parts). Though with the enormous caveat that I haven’t gone beyond the Peopoly standard resin, and Photocentric high tensile resin. Don’t want to jiggle the handle too much…


Thanks for the info, I´ll try the standard blue resin with the same parameters to see how it goes.


i think im going to give up on the fep vat and self level build plate, no support for fep vat, no good settings for normal resin no solid understanding of how to print larger objects every print a fail even though those stupid pillar test work and are set to 10.7
with the fep vat you cant see through the side so you have no idea if its actually printing… i never got a successful print
self level build plate is so messy its better to use the original,

so far there’s nothing but negative issues with this printer, to be honest id rather have my money back.


The printer is actually very good but I do have to say that the FEP vat has been a disappointment. Go back to PDMS and try the self leveling vat - yes its a little messier but it does get good prints once you set it up correctly.


I think I’ll be ditching FEP myself as well. I’ve had 3 failures out of 3 attempt. Seems alright for small prints like the ring test and maybe miniatures, but it’s so damned sticky it rips the supports apart, no matter how many I place. I’ll be doing one more attempt with some thicker supports, but I don’t have any faith in it working.

I even tried adding some Rain-X but that didn’t seem to have any effect unless I got the wrong type.

Main reason I bought the FEP vat was because I can source the FEP film easily in the UK - It’s nigh impossible to find the solar encapsulate for resurfacing the PDMS vat in the UK and £35 plus postage and customs charges with a 2 week delivery time isn’t something I’m willing to pay considering I’m still yet to have a perfect print myself.


Seems like similar problem
The setting parameters can be seen in picture .
worked with:
cura 2.6.2-14 (slicing) 50 micron, latest setting, add additional Base (raft) in cura
Chitu (supports)

FEP-VAT was clean of debris prior to printing
Leveling - perfect

Print result - disaster - Layers separation ! ! !
BTW- first layers were successfully attached to Z Block

What’s wrong ?
It’s me or the VAT ?
Should I give up the FEP-VAT for large parts (never tried other than FEP-VAT)


I am experiencing a lot of issues with the FEP Vat as well. I am using the XYZ software for adding support, and even after using the automatically generate option on highest density and thickest support my prints will not come out clean. I just seems that the FEP is too sticky to print properly on.

I will try and replace the FEP to see if that will clear up anything, otherwise I will be giving up on is as well and move back to the PDMS. For something I’ve waited to so long it’s quite a letdown really as the printer can produce some outstanding results (just not with this vat it seems >_<)


I have just bought the FEP Vat together with the easy to level build plate and i had the same experience as all other people here. Not any of my prints were successful… until i realized that the TEMPERATURE OF THE RESIN is of significant influence to the printing process as well. As a matter of fact, after some googling i found out that the Formlabs Form 2 printer all have a heated resin vat. As this is (process-wise) one of the very few differences between the costly Form 2 and our Moai i thought I would give it a try to heat up the resin before printing.

I did that using a hot air blower and heated the entire inside of the printing chamber of the Moai up to 38 degrees Celcius… (so that’s not too accurate :slight_smile: and I kept all parameters exactly the same…and… in stead of a failed print i had a 100% successful print…

That made me decide to build a heater inside the printing chamber of the Moai.
A silicone 220V 200 Watts 200x200 mm heating element stuck to a 200x200 mm aluminium plate and a thermostat will do that job just fine and is going to cost me approx $30,-

Does anybody have experience with a heater inside the Moai?

Edit: Sorry… I found that the topic “chamber heater” already exists in this forum… but still The 3D printer silicone heater (220V) that does not need a power supply (and without a fan - so… silent) has not been mentioned there. I will get back to this topic as soon as I have build one.