Print Quality Issue with Black Resin

Sure, I had to scale it down to embed, but here it is on Imgur:

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Oh, and no I haven’t tried .1 for anything yet. I’ll give it a go w/ grey and post it here. Between grey and black at .5 the results seem similar, but grey is easier to see the details in I think, esp in a photo.

Hey all,

Thanks so much for taking the time to voice your concerns about Black resin!

I can’t offer many specifics at this time, but I can say we’re absolutely aware of these concerns, and we’re working hard on software improvements that will be released as efficiently as possible.

I’d expect there to be significant improvements over the next few months as we are able to implement feedback and data into software/process improvements now that thousands of units are in the field. Please keep the feedback coming! We look at all of it and take it into account.


Thanks for letting us know DKirch. Any details you can offer would be great. Timelines or an explanation of the problem for example.

I printed the tolerance test linked from the FormLabs white paper titled “Engineering Fit: Optimizing Design for Functional 3D Printed Assemblies”.

I can’t insert the test pin in any of the holes. I can get it about halfway into the biggest hole, but it’s very tight.

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Have you ever checked galvo mirrors and the main mirror inside of your Form 2?
Especially, you’d better check signs of contamination on the galvo mirrors by fine dust.
A flash light is good for inspecting the mirror surface.
If there is fine dust on the mirror, there must be contamination by the power of the laser beam.

After cleaning all optical passes. my Form 2 was reborn and its print quality got super fine. :wink:
You’d better follow Formlabs instruction for it.

Good luck~



Thanks for printing the same model on yours.
Now, I see I am not alone on this ship… :sunglasses:

Yes, your print seems also over-cured, but a little better than mine.
I have tested other standard resin types.
Unfortunately, all of them are in the almost same quality.
The worst one is with the white resin.

Shown below is printed with 0.05mm layer thickness, white resin on Form 2.

Shown below is with the same layer thickness, white resin on Form 3.

With clear resin on Form 3, and somewhat better.

With grey resin on Form 3.

I tried 0.1mm layer thickness with the grey resin, but worse than 0.05mm.

Please check the Formlabs PreForm release notes. You can find layer thickness setting improvement notes on version 3.1.1, but most of them seem not perfect at this moment as DKirch mentioned.

I had expected better results with the grey resin because Formlabs showed a feather(wing) print sample, but was disappointed by my result.

All prints seem pretty over-cured.
Shown below shows some dimensions of the test model.

However, the results are all pretty chunky.

As you mentioned, we cannot get any kind of clear gaps.
Form 2 print shows clear gaps. (below)

However, the current setting of Form 3 is very serious.

Now, I am totally tired of keeping cleaning my only one resin tank for changing resin types.
At this moment, I give up testing mine.
I believe it seems quite better to wait for the next PreForm update.

Anyone who has not received Form 3 yet, you do not need to envy people already got it.
We are struggling with it.
Also, Formlabs mentioned ‘the next few months’ for its software improvements.

When galvo mirrors or the main mirror of Form 2 is contaminated by fine dust, we usally get a very similar result.
However, Form 3 is new, so I hope that all the issues are due to parameter settings of the software, not due to the LPU or the foggy resin tank film.




Yes, I also hope this issue is due to the software, not the hardware.


Thanks for doing all that testing, in your own time, with your own resin!

I have to say once more, I’m not impressed at all with how FormLabs handled the Form 3 release. We are currently only printing Tough resin with our Form 3 and were pretty satisfied by the quality (less so by the speed that is lagging significantly behind the Form 2 at the moment).

Good to know that it isn’t worth it to clean our (for now) only resin tank and use it for Grey, but that we better keep those prints on our Form 2s…

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Yes, I also expected better quality.
As you know, the higher the expectation, the greater the disappointment.
I hope it can be solved as soon as possible.

However, another big unexpected difference is the print time.
It is more than 1.5 times longer than by Form 2.
A small and simple model takes similar to using Form 2, but there will be much longer print time for many models or any big model.

My print samples are all tilted.
I will post results with the flat layout.



Thanks for your reply and explanation.

I believe an official notification or announcement regarding it will be better.
As you can imagine, Form 3 users are all struggling with this problem, but most of them do not know why it happens.
Frankly, I feel like that Formlabs is covering up this issue recently.

I could not find any official information regarding this issue.
Only few people on this forum can get this kind of important information.
I thought mine was defective. Many Form 3 users think like me.

I hope this issue can be solved soon.


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+1 on everything JC says. I think he and I are getting very similar results on this part across all the resins we’ve tried.

Folks keep saying they can’t get tanks. After my first few prints I ordered 3 more tanks and got them swiftly. I had emailed support asking about the listed 3mo lead time on the website and was told that since I already had my Form 3 it wouldn’t be a problem, and sure enough it wasn’t.

Definitely not feeling confident Formlabs has a handle on the problem and a clear path to a solution. I’d been considering getting into 3D printing for some time and the announcement of the Form 3 was the impetus to dig in relying on the Formlabs brand to preorder it w/o waiting for reviews. It seems that may have been a mistake. Not sure if I should wait around for a fix or see if I can return it.


Usually, Formlabs announces a new update in a month, and the latest PreForm was updated on Sep. 19th.
I believe that they will find solution quite soon and that the mechanism of Form 3 seems better than Form 2.

Just I am wondering why Formlabs did rush to announce and begin to sell Form 3 although they did not achieve acceptable resin settings.

I believe our feedback regarding any print issue will be helpful to improve Form 3.

Now, I am trying to print test models with a different approach, because I like to see how the X-axis movement of the LPU affects the result.

with flat orientation.

@Joonghyun_Cho, thank you for taking the time to do these tests. Your results are representative of what I’m experiencing on my Form 3 with white resin.

Don’t beat yourself up too badly, I drank the same Kool-Aid.

Back when I upgraded to the Form 2, I hung onto my 1+ because it supported faster (0.2mm) printing with Clear. But the Form 2 turned out to be superior in every other way, and with the announcement of Draft resin that last advantage became mute. Meanwhile Form 1 tanks and replacement parts became harder to acquire, and the “lifetime” discount on resin bottles for Kickstarter backers ended.

As we speak, Formlabs marketing is making a big fuss about the improved print quality of the Form 3. Given the smaller laser spot and perpendicular beam with spatial filter, there seemed good reason to expect those claims to hold up. I also could have sworn reading somewhere (or hearing) print times were supposed to be slightly faster than the Form 2. I even spoke with a couple people at the user summit who had their hands on the printer before release and didn’t flag any major warning signs.

All that left me with a pretty good feeling - enough to grab my discount code and place pre-orders for both the 3 and 3L, and eventually sell my Form 2 along with most of its consumables (including a dozen or so trays). I wasn’t going to be caught on old, unsupported tech this time around, and made the decision to jump all-in to the new ecosystem. I figured there’d be some inevitable growing pains on initial release, but (at least in my own experience) Formlabs has generally had a decent reputation for customer support.

Reading this thread and a few others has me concerned. From what I gather it seems the Form 3 is slower, louder, smellier and (for the moment and at least for some types of prints) doesn’t match the quality of the Form 2. I really hope the print quality issues are just a matter of the software team dialing in settings for the resin profiles.

Thanks everyone for all the hard work to investigate and compare; keep the photos coming.

rkagerer and jbrownson,

Yes, Formlabs has done the great achievement for Form 2.
I believe they will do their best for Form 3 and Form 3L too.
Formlabs is one of the most reliable companies to me.
I think they need some more time at this moment. I like to wait and give them the time.


I appreciate all the optimism. Good to hear the journey w/ Form 2 was similar and ended well. There is certainly a lot to be impressed by in the Form 3, and it makes sense that the new tech should perform better when dialed in. The surface finish is quite remarkable, esp in clear resin.

I did that same print in .025 btw this this result. It’s pretty comparable to the .05 results I got earlier imo.


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Not impressed with my Form 3 either. Apart from the issues highlighted about it is much noisier than my Form 2, a lot slower to both get ready to print and to actually print. Wish I had bought 2 more second hand Form 2’s rather than the Form 3 now.



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@Komodo and @jbrownson,

Oh! The new version(3.1.2) of PreForm was released today.

  • Improved the 100 micron layer thickness setting for Grey Resin
  • Improved the 50 micron layer thickness setting for Dental Model Resin
  • Improved the 50 micron layer thickness setting for Tough Resin
  • Improved the 25 micron layer thickness setting for Color Resin

I am going to test the new grey resin setting.


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This is a test before the recent PreForm update(v3.1.2).

All models are flat, not with an angled orientation. Flat layout seems better than angled.

Gaps parallel to the LPU movement direction are clearer.


This is the result of the recent PreForm version 3.1.2.

It seems to get a little better than 3.1.1, but not enough for my expectation nor even close yet to the result from Form 2.

PreForm 3.1.2 (below), 0.1mm layer thickness

PreForm 3.1.1 (below)

PreForm 3.1.2 (below)

PreForm 3.1.1 (below)

Winner Winner Beta Tester! :crazy_face: Why do I keep doing this???