Form 3L Issue Seen on Video!


@CraigBroady Thank you for your response. I can understand now what Formlabs’ position must have been regarding this issue when the video was shot. I understand how difficult it can be to match engineering and development time with marketing time.

I was not sure what might have happened so I wanted to be assured. I really appreciate you reaching out and clarifying the issue seen. This gives me confidence to order the Form 3L. As I said before, when all is said and done, I have no doubt the Form 3 and 3L will be the best SLA printers in the market. The images are proof enough that the 3L is capable of large prints. I am really excited about 3L’s capabilities.

I do have a question though. Due to large parts being heavy, do you notice any parts warping? Low peel forces might mitigate that issue but have you noticed anything?

Also, the flexible resin tank is probably the main point of discussion among the community members. Would you be able to provide any info on the life of the tank? There is no pricing available for the resin tank for the 3L, but I expect it to be expensive, knowing that the smaller 3’s tank cost’s $150. Just want to get a rough estimate on how long it’s expected to last with appropriate usage.

Nevertheless, thank you for your feedback. I am sure this will help clear doubts if any.


Glad I could help.

I haven’t noticed warping on parts that could be attributed to weight, though I could imagine some scenarios where that could happen. Because we expect large and heavy parts to be printed on the Form 3L, the entire Z-axis system (tower, build platform, carriage, guide rail) is designed to deflect negligibly under those loads. Same thing for Form 1, 2, and 3, but just a different scale. Because of the linear nature of the LFS peel system, I would not expect peel forces to be notably higher than what we would see on a Form 3. If the part is insufficiently supported under its own weight however, (for example due to inadequate supports) then I could see warping becoming a problem. Again, similar issue to any inverted SLA system—it’s just a matter of scale.

As for the tanks, I don’t have too much information that I can share right now. I can tell you that the Form 3L tank is based on the same technology that we use in the Form 3 tank. I’ve had a Form 3 on my desk for about four months now and it sees a print roughly every other day. For the most part, I’ve used the same resin tank, and I haven’t yet noticed any signs of degradation. I’ve had one or two failures, and they have been remarkably easy to clean—no “oatmeal” in the tank means no filtering required.


That’s positive news for the tank. Regular usage, minimal degradation, and low print failures. And since Form 3L is based on the same technology, I think it should be the same quality if not better.

Ah yes. The dreaded oatmeal. Glad that the new system reduces cleanup time while increasing the print quality remarkably. I saw some images of clear resin prints. They are amazing. I did a project with a Form 2, 3D printing lenses, using an article posted on the website. There was a lot of post processing required. But with this new machine, I feel a lot of post processing steps have been minimized.

Thank you for the information Craig.


@CraigBroady the no “oatmeal” had me confused, could you elaborate on what you see when you have a failed print on the Form 3?

What is the process for cleaning out the Form 3 resin tanks?


“Oatmeal” is the term sometimes used to describe a failure mode on the Form 2. The laser will cure a layer on the tank that does not attach to the rest of the part, then the wiper removes it from the tank bottom. Repeat many times and your resin tank is filled with these small cured bits, leading to an oatmeal-like consistency.

On the Form 3, the mixer is not used every layer for many resins. That means that the path drawn by the layer stays stuck to the bottom of the tank. Cleanup is simple: you just use the “tank tool” in the finish kit to scoop out the pancake-like cured bit.


“Oatmeal” and “Pancake” failure modes. Clearly these were discovered and coined while eating (or dreaming about) breakfast after overnight print trials. =]


I’m always dreaming about breakfast, Brandon


This thread has sparked a touch of curiosity about the the 3L.

How much resin does the large speaker print take?

… and does the printer use the cartridges in parallel or sequentially? ie will we have to change both cartridges at the same time or will it report something like “Cartridge A is now empty” so that it will carry on printing while the cartridge is changed?


The large speaker is about 2.5L.

As for cartridges, I believe the current plan is sequentially.


@CraigBroady I love the no oatmeal feature of the Form 3. Very soft failures when a single item on the bed doesn’t stick and I don’t have to filter out the sludge. Failures are quite rare on our 3 so far but every once in a while an engineer gets lazy and doesn’t support properly or puts a 0.010" walled cylinder on there. It is nice that it doesn’t impact the other parts.