Print Quality Issue with Black Resin


@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.



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.




@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.



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???




Right! This obvious slower print time is due to the LPU movement, so it doesn’t seem able to be reduced a lot.
Also, much noisier due to fans and the LPU moving sound, but it doesn’t seem to be changed.

Therefore, it has to have some other outstanding merits.
O.K. The design is great, and I love its several new functions.
However, I hope the print quality at least can be remarkable after tuning up the resin settings.



I think that you’re correct that some of the slowness is due in part to the LPU movement, but I think that one other reason is the smaller laser dot.

The 85 micron dot is 40% smaller than the dot of the Form 2, so it stands t reason that the laser has to spend more time to fill in the same area as before.

So unless they figure out how to dramatically speed up the one galvo (X direction) and the LPU movement (Y direction) I don’t think you’ll see much improvement on the speed.


It seems that given the stats of the Form3 that this is something that should be able to be fixed in a software update


Here’s the test print on my Form 3 in White V4. I didn’t take a very good picture, but as you can see, the small holes are completely filled in and there is no gap between the shapes along the back.


.1 or .05 resolution? I just did a .1 and it looks about the same as yours (hard to tell where yours filled in on the front though) but was going to do .05 based on results from above. Won’t run it if you did .05 though.

Form 2 below on left, Form 3 on right. 0.1 resolution. I think this demonstrates that my Form 2 need some maintenance more than the Form 3 being way better. My results are better than Joonghyun’s from post 17 above though (for Form 3).


Thank you for your efforts at Formlabs. Nevertheless it is very disappointing to me that I’m used as a beta-tester when buying a newer machine that is supposed and announced to be much better than the old one.


To those having issues with speed and noise, are you running the latest firmware (1.3.4)? We changed it to turn the fan off when the printer is idle and have been working hard to speed up print times.


@piGuy Your result looks almost the same as mine. Current software settings seem to be over-curing, such as strong laser power with slow scanning speed?
I doubt that the better surface quality which Formlabs has put up also can be affected by this over-curing.
Let’s wait for the next PreForm and Firmware.



Your Form 3 result seems similar to mine too.
This quality can’t be accepted by my field. I am wasting my time and resins with this current print setting. Perhaps you all too.

Also, your Form 2 has some serious issues.
You would better check any contamination on the galvo mirrors and the main mirror. If you use a regular resin tank(not LT), the foggy silicone surface can cause the issue.

You should be better to contact Formlabs for further instruction for it.



Thanks for the information.
Yes, I am. Unfortunately, it can’t solve this print quality issue. The fan off function during idle status is much better.
I am looking forward to any better result on the upcoming update of PreForm and firmware.



3,607 hrs on Form 2-1
4,093 hrs on Form 2-2
1,503 hrs on Form 3
7,763 hrs on previously retired Form 2 (interesting this is almost exactly the summed total of my two current Form 2’s)


It should have all been done before the machine was released…now we are all guinea pigs for testing resin at $150/L with sup-par results. The management has not learned past lessons, and rushed this machine out to beat some competitors, likely…without bothering to get the settings right for the small subset of resins you can actually use on the Form. 3. If you haven’t bought a Form3 yet, I would wait. Especially if you have a Form2 that’s working. The Form3 is not ready for serious work yet.