My experience with the Form 4(B) so far/ Semi-Review from a Semi-Industrial User Perspective

[eaglechen]

Hello there. I would like to start a discussion for the Form 4 for some perhaps necessary feedback to hopefully make this product better.

You may have been like me, couple months ago, scouring the internet for reviews and experiences for the Form 4. I am here to offer you a perspective from a semi-industrial user. If you are shopping for a resin printer as your hobby, this probably should not be a consideration – the material I have thrown in the trash as failed prints over the last 2 months would pay for a desktop system nowadays that can probably produce similar results on paper albeit with a lot more tuning and perhaps questionable material properties. My business consists of essentially a service bureau and non-profit work providing general purpose educational models, functional prototypes, and very limited and niche production parts with the engineering materials. I have not quite dared to venture into biomed projects for the fear of chucking 100 dollar failed prints in the trash. I received this 4B at the end of the May, and I assure you, I have put this printer through its paces. I think we are up to 300-400 hours of printing on this unit, so printing time of around 50-65% everyday nonstop for the near last two months in mainly general purpose V5 materials and tough 1500. For reference, I have used every Formlabs SLA product since Form 1+ in some professional capacity, and paid for all but one of all of Formlabs’s SLA printers. I am certain that there are people a lot smarter than me working in additive in the field and especially at Formlabs, but I am certainly not the average user than Formlabs claims can learn the in and outs of this system in 20 minutes. You will probably will not have a good experience with this product with no training or experience.

Obviously, this is my experience and will contains my personal opinions. Just getting that out of the way. I believe Form 4 can be very game changing in the long run and can outprint some of the industrial DLP printers out there in a lot of settings, but we are a few but very large steps from being there yet in my opinion.

If you are too lazy to read, I will summarize as follows: unless you are a dentist who only prints little and simple models without supports directly on platform (but you can probably buy something more reliably and with more throughput with the budget of a dental lab), Form 4/B cannot produce parts with the website claimed reliability or tolerance. I do not mean that the printer cannot do it reliably, I mean the printer cannot print a lot of parts AT ALL in almost all materials. I cannot, at the moment, recommend this printer as an “industrial” experience. If you buy this in the hopes of supplementing your business or getting into additive manufacturing, you will face a tremendous learning curve and will probably have a bad time. I will now break down this claim, this is a long post so feel free to take your time:

Form 4 definitely represents a step forward in terms of print process, speed, and machine hardware performance, but it comes nowhere close to the reliability of its claimed competitors in the industrial realm at the moment. The print settings are not mature, and post processing consists of steps that are very finnicky and geometry dependent even in the hand of a very experienced operator. None of that matters however, as the printer, at the moment, cannot produce real world parts with accurate geometries anywhere close to the claimed tolerances of like +/-0.2mm or whatever percentage, especially in large, blocky models without warping in EVERY print. Engineering materials such as tough are much worse. Here is my overall print success rate with 10-20 cartridges of materials printed so far (I’m really not making rocket parts nor trying to satisfy the best artists on the planet, these are all pretty simple with reasonable expectations). This is without considering cure failures (where the thing prints, but it warps in the cure so I have to remake it and hope another orientation works):

I think wanting at least 90-95% print reliability in the hands of an experienced user is not asking for too much right?

Client expectations are sky high today, people expect 3D prints to be delivered overnight, perform as high as strong plastics injection molded plastics, and contain high detail and surface finish the same as that 5 cent injection molded part. If I give clients a part that does not stand up at least to perfect visual scrutiny, they will not even accept it for free. I chose Form 4 for the surface ability to offer fast material swap and surface finish at a lower price for a similar experience on paper to the more expensive industrial DLP systems. It is abundantly clear the direction Formlabs is headed towards with Form 4—industrial 3d printing or at least the low end of it. The fact that I was not allowed to purchase the Form 4B variant without a medical service plan should serve abundantly clear for this reason ($1000/ year, of which I put to good use already). I do welcome this change – 3D printing is a tool for me. The dream of additive manufacturing is CAD in – part out reasonably reliability, and I am willing to pay a reasonable price for this, and if the Form 4 works as advertised it would actually be tremendous value. Unfortunately, this has not been my experience so far. I do feel like I am paying this premium price to beta-test a printer not particularly superior to a desktop system I can tune and fix. Material properties and software aside, I am definitely not achieving industrial print quality. Again, I have thrown away warped and failed prints with the same price of some desktop mSLA printers.

Let’s start with some good from the experience:

1. Sales is very responsive and answers all my questions, on time and even same day. A superior experience compared to convincing $50000-250K printer companies and their dealer network that I matter (a lot of them do not call me back).
2. Support team all need an immediate and big raise. They have glued this experience together and are the only reason I still have this printer. Their limitation is they are only trained on customer support. They are fantastic at reading from a script and giving you free material and consumables to troubleshoot (again, why I still have this system). However, they are not engineers and cannot offer technical solutions or tell me what the engineers are thinking. I was basically politely told I cannot talk to the engineers or really anyone outside the support team as a liaison. I understand this from a business standpoint, but with any industrial system usually you work through a distributor with engineers and technicians on staff that I used to be able to access with a direct phone line for actual technical troubleshooting.
3. Printer was delivered promptly. Printer, cure, wash all perform without hardware issue and printer was calibrated fine. Form 4 hardware is solid and has tremendous future potential, and in a different league compared to Form 3 in my opinion. It can probably print with better supports and even go a little faster (room for a lot of improvement). The problems I will detail are likely software and print settings fixable to some degree. No hardware has failed (yet).
4. It is as fast as they say. Maybe just as fast as the desktop systems and industrial DLPs today, but it does seem to achieve whatever print speeds Formlabs markets. Most prints 5-7 hours or less. I will admit it does hurt a lot less throwing away a 3-4 hour failed print vs a 30 hour one…
5. Print volume is bigger than Form 3, I can fit 99% of parts I have come across on it.
6. New cartridge system is robust. It’s all RFID now, no issues for recognition. New filling system is fast and good. The price of general purpose is now lower. How many companies can say they reduced price these days huh? That being said I think the resin estimate by Preform and resin management by dashboard is still basically not useable. It’s not accurate by a long shot, and I mainly just guesstimate and hot swap cartridges in the middle of the print when material runs out. I do not believe the material use estimate to be accurate either, in reality I budge about 20-30% more material than Preform estimates.
7. New general purpose materials have much better functional properties; I can make smaller details survive peeling off supports. All prints in multiple materials capture fine detail, good anti-alias tuning, and look great with fine surface finish, much better than Form 3 and crisper than some low end desktop DLP with a claimed 38719837908109423K display and 1 nanometer micron size pixels. Circular layers are anti-aliased and round. Cosmetically and on paper accuracy is better than Form 3. However, at this moment this does not matter if the overall print warps. A lot ore on this later.
8. Print time estimate seems to be more accurate.
9. The tanks wont leak and will last longer from redesign, no matter material. However, I do question how much better is the textured surface + so called low force display technology versus the desktop solutions. More on this and peel forces later.

I also will mention that you do probably not want this printer on your desk or in your office room. This thing is loud. The cooling fan of the LED array makes this thing sound like a jet airplane taking off during printing. The wiper is equally fast and furious. The general purpose resins do not really smell, but the engineering ones do a little. Additionally, you probably also do not need me to explain what a 5 gallon bucket of isopropyl alcohol will smell like either to you and people around you. My point is you really kind of need a dedicated workspace for this thing.

By the way, a lot of my parts do not fit in the legacy Cure unit, of which is still being sold with Form 4 as a package. Formlabs knows and discloses this; if you look at their social media and such you will see everyone there using a CureL meant for the 3L to cure the parts off the Form 4. The CureL (around $5K) has a beautiful interface, can heat faster, and exposes the parts much more evenly with a lot more light intensity that will actually achieve the part properties consistently for engineering materials much better than the regular cure. This is fine and I have worked around it, but in reality you really should have the full work flow of two washes (one to do initial wash and one to fully clean the parts) and the big CureL. Now we are looking at around $10K for the regular Form 4 and around $15K for the 4B workflow. This is not cheap and very much almost twice the starting cost of the machine itself. Just letting you keep in mind that you will probably need this for better throughput. I personally think the legacy cure needs a major redesign.

Now you have read so far, let’s begin the somewhat deep technical analysis of Form 4’s current printing deficiency that I have personally encountered. Fortunately, I do think these are software fixable or at least software mitigatable. Now, timeline wise is anyone’s guess. Realistic, I estimate 1-2 years because a lot of these refer to the print process and settings of the machine itself.

Firstly, support material generation represents a definite regression compared to Form 3. At the moment, support structure is much denser, using much more material can be difficult to breakaway in most cases. Forget the ripping the part straight from the support material experience with Form 3, I had to carefully work and use cutters in some cases. Dense support structure frequently cut my hand during removal work. I first noticed this with smaller Grey V5 parts being welded to the parts. I found the default Tough 1500 supports being essentially welded to the model after curing. Support team informed me that Form 4 contains higher peel forces compared to Form 3, warranting the denser and thicker support structure and touch points. Features such as breakaway structures are not available, and for large models and certain settings Preform will actually anchor the parts down in places with big (up to 1mm) support dots. I do think this is actually necessary for large models to print reliably, as you can literally hear the printer ripping the print from the film for these layers. I have tried smaller manual support point sizes without reliable success outside cases of using small points (0.3mm) to support detail and 0.5-0.6mm normal touch tips to actually anchor the model with some success. The astute observers here may notice this is the almost exact support tips default paraments offered by some other desktop 3D printing slicers for cheap mSLA printers, making me question whether the Form 4 actually offers lower force in peeling in a real-world useful and not purely academic way. I was told to turn down tip and density, but I experimented with this with little success. Keep in mind this will cause detachments and warping during curing with inadequately supported model. Furthermore, the similar experience of editing supports for even 1 hour for large projects to achieve a better (or barely printable from probably unprintable) results has not changed. This is not a new problem, automatic orientation and support generation is just not enough, hence why I do think new users face a very steep learning curve far from the “learn to print in 20 minutes” experience.

Secondly, how this all interacts with the curing process is inconsistent and in reality not reliable for me to depend on. I think in reality testing by Formlabs in this regard is unfortunately minimal. Luckily, the general purpose materials now can be cured in just cold conditions with no heat and just LED blasting for 5 minutes. Formlabs has put out confusing guidelines with some youtube videos and online posts recommending support material before curing, and some saying for most geometries after curing. The support team recommends for most materials after curing to remove supports, and I agree with this. You really need to cure on supports for any hopes for accuracy, especially for the engineering materials with like 70C-80C curing. The glass transition temperature of the engineering resins are substantially lower than the curing temperature, meaning the material will soften and turn into a blob and bend without supports anchoring them down. Even if you cure on supports, the weight of heavy models will cause the support lattice to bend and collapse, probably causing dimensional inaccuracies in the part itself. This makes the post-cure process very finnicky, and often I just have to pray that the model wont bend or reprint in a different orientation with supports to have a semi-successful cure. The tough resins are, well, tough, and support removal for a large model after curing will suck. The general purpose V5 stuff can benefit from curing on supports, but all the engineering materials are pretty much guaranteed to warp if you do not cure on supports. This process is so inconsistent it’s almost artistic in nature. But hey, this is nothing new if you used Form 3. Even if you cure on supports, the weight of some large parts will cause the support to bend as the cure heats up, making me guess the final part dimensional accuracy will be affected (it is, just fortunately has not caused a problem for me yet).

By the way, we are at the point that you should consider that the entire workflow is slower than the printer. Preparing the file for 1 hour + 20 min wash + 1 hour curing + 1-2 hours sanding to make it look good for engineering materials is easily twice the duration of like a 2-3 hour print. Just something to keep in mind. It’s realistically 1-3 hours per print outside the printing itself before part in hand. A kind of no-brainer, but Formlabs kind of brushes over this point. Not a huge deal, but a lot of hands on work before part in hand for sure compared to industrial FDM or even SLS. Not probably a weak point, just part of the process.

Let’s get to the bread and butter issue of this post. I am willing to accept all that, and work around all those limitations. The main issue with this printer is actually this. Currently, the printer cannot produce expanding areas, especially the part where the models first attaches to the supports accurately. You can especially see this with spherical models. Furthermore, the much larger issue is small expanding areas and most likely the internal forces of layer curing leads to the first one inch of the printed model (anywhere where a model starts from supports) warping away significantly from the rest of the model. This happens to EVERY model, I just can hide this better in organic and artistic things, but for jig and machine replacement parts that needs to be accurate, forget it. In summary, every model printed off the Form 4 will warp right out of the machine. The general purpose materials are bad (grey and colored materials slightly better than clear), the engineering materials are even worse. It does not matter how thin or thick the model is, the part will warp. Interestingly, support tips do not fail during this process, and turning the supports up to 1mm will not help. The internal stresses of the model are high enough that it bend the support columns. Currently, software does not address this, and some models that printed relatively ok will bend on its own after a few days in a normal indoors setting.

Here is a highly scientific diagram I drew by hand to illustrate both issues:

Warping:

Poor expanding area performance (basically, the underside of a sphere/ rod will show ripples/ staircases, also overhands all look terrible and bends upwards if unsupported on both ends)

Here are some pictures I have to fully document this issue:

Hard to see by entire one side of architectural model caves inwards where it first attach to supports by like 10-20 degrees:

Thin object oriented 45 degree upwards from X and Y axis, warped in both:

Badly warped architectural model straight from the printer with corners pulling upwards (client rejected this part even for free):

Test array I have created of blocks, you can scroll through my Google drive to see more and .form files for things, moral of the story is no matter orientation the 1st inch or so of the model has to be sacrifice and warped away from the rest of the part:

5mm+ warping of Grey V5:

5mm+ warping of clear v5:

5mm+ warping of Tough 1500:

Machine part jig, you can probably guess how these were oriented. Bottom attachment is supposed to be a square, this is after orienting these differently and printing like 3 times to minimize damage, ultimately did not fit on the machine.

To emphasize, this is directly out of the printer. This happens doing the print process. I personally guess the cause to be the settings not yet fully optimizing the internal stresses during curing of each layer. This is not bending during wash or cure, I know what that is and that happens too unfortunately in addition to this. A lot of these models are literally ripped from online sharing websites for desktop FDM printing. I am not building rocket parts, and I would like to think my expectation of the advertised 0.2mm printing tolerance to be reasonable. Small models can warp up to 0.5-1mm, large models 2-5mm. It does not matter whether part is 1 inch of 6 inches long. It is admittedly frustrating seeing a $500 FDM printer people built in their bedroom print a part with straight walls and flat bottoms. Sure, they don’t look good, but they work and fit… I even created an orientation test model to document this issue and put the .form files in the Google drive link. There are a lot of photos here and I unfortunately do not have the time to explain everything, but I trust you all can browse this folder and figure out the gist of my problem:

https://drive.google.com/drive/folders/1OP1raLwcLq2u-i0olpYbg8TqfCSYyP9k?usp=drive_link

By the way, I would like to think I have tried every orientation, every trick. If the printing technique (different orientation, support editing, welding the model down with 1mm points), I have tried it. Support team has ran out of idea as well… I have been in this game for a while, and I can tell you for sure this is probably more so a printer print process and settings issue. It is frustrating that this printer can blow the best sculptors on this planet out of the water but cannot print a straight edge. Also, if you look at Formlab’s website you will see most advertising models and accuracy videos mainly printing little cubes and stuff directly on the platform of which they take a caliper to. Unfortunately, basically no real parts are designed for this, the Formlabs online guideline of 10-15 angle for a flat surface is nowhere near enough. Support recommends the in reality 30-35 degree self-supporting angle almost all DLP printers do. Also, I have indeed tried printing on platform as well. You can tell Preform is not optimized for this, I really was never able to get this to work for models with even a large flat surface. Straight overhangs will be ruined and support material anchoring part of the model directly on platform will usually fail for some reason from support cutting off and not pealing halfway through and lead to model explosion. Furthermore, this is not recommended anyways and severely restricts the useful geometry that can be printed.

So, where does this leave us? I do think this machine has potential, regardless of the time it takes to unlock said potential. I recommend Formlabs to investigate the following:

1. Investigate the effect of print settings on early layer performance and warping during print process. My personal guess would be to investigate the effect of temperature and heat generated during polymerization on these early layers alongside exposure (a VERY educated guess). I would highly recommend a read of the work done on the second half of this article (a much more important suggestion): Preventing Warping of Resin Printed Pieces: Alternative Way of Fighting Resin Shrinkage – mind.dump()

2. Retune early layers for better overhang and expanding area performance.

3. Retune support materials for better density, breakaway structures like Form 3, and smaller touch tips.

4. I personally think the new peel forces and kinematics of Form 4 should warrant a support material thinking rework, I don’t think the support material guides based off of Form 3 and older Formlabs products will work going forward. Something like this system may be beneficial:Orientation & Supports Assessment It is very weird to me that Formlabs seems the only printer in the DLP/mSLA space that pushes for orienting parts at like a 30 degree angle and have no advanced settings such as editing support material bracing and selecting different kind of supports. I get why this is for part orientation, you can’t lay things flat on the Form 4 and get a straight part. However, here is a competitor stacking a bunch of little things in one build what I do not believe the Form 4 can print (the straight edge overhangs will be messed up and the small contact on build plate for an entire stack of parts will detach). Obviously this is possible with a similar print process:
   

   

5. Arraying models vertically for making a bunch of parts at once like the picture above should be a Preform feature. All your competitors do this in some way already with their software from launch.

6. I would buy a Form cure redesign that would allow you hang the build plate like hanging on the Form wash to cure the parts and completely fit everything in Form 4 instantly. The kinematics of the support materials are designed seemingly for pulling versus having compression forces after already being softened after curing heat. The bro-scientist in me thinks this will lead to much more dimensionally accurate curing. If a larger version of Form 4 ever gets made, I think this will be crucial to cure those larger and heavier parts with heat.

7. This is the least concrete and most vague but I think nevertheless an important suggestion. Here is a sample of Formlab’s two largest competitors in functional material. Ironically, the top end DLP machines are moving towards a completely open system where materials are mostly 3rd party provided (and actually at a reduced price compared to Formlabs, albeit case by case and usually only a small cost savings). Anyhow, here are some datasheets with their engineering materials:

• https://www.loctiteam.com/wp-content/uploads/2023/05/W00834.pdf
• https://move.forward-am.com/hubfs/LFS%20Documentation/General/Printer%20Workflows/LFS_Stratasys_3d_printer_workflow.pdf?hsLang=en
  Notice these materials mostly cure at room temperature. I believe going forward it would be in Formlab’s benefit to investigate relying instead of heat, utilizing a stronger cure chamber with higher power LEDs to blast the parts to achieve the same amount of energy. I know for a fact large SLA systems rely on this, and should create much better dimensional accuracy and cure speed allows for support removal before print. I am not a material scientist, and this does sound like questionable bro science, but I think that the fact these work flows exists and the Fast Cure (which from what I understand does not heat but just blasts the parts) gives some credit to this possibility. Ultimately, removing supports before curing is much easier.

8. Speaking on materials, more long-term durable material such as dual-cure and at least environmentally stable materials enabling niche production roles for end use-parts will be crucial. I know PU exists, but I mean like an actual material I can realistic use without like a materials labs and multiple dry cabinets and a multi thousand dollar lab setup. All your competitors have this already.

Again, there are much smarter people than I working in the AM field and at Formlabs, and my suggestions are only my speculation based off of the print defects I have experienced and what I want out of a system. If problems 1-3 above can be mostly solved, I would be already be ecstatic. I bet Formlabs is working on some of this anyways. The point of this post is to encourage collaboration and make a better printer hopefully in the end to solve my issues. I know how hard engineering and building a product like this is, I just hope we can come to a more mature product faster.

Edit: Also quick update on a more optimistic note as of like last week (7/15ish). Support gracious sent me a cartridge of Precision Model, it is for now as accurate as they say. It can print everything every other material has failed at (and continue to fail at). It is not perfect, but it is at least 90% there and definitely printing client-read models without warping. I happened to turn the lights of in the room one evening and was observing, noticed that most layers and printing a double exposure. I have no idea what this actually is of course, but it could be a primitive/ different version of the blog post I have mentioned in suggestion #1. Whatever it is, it works. Parts do not warp and internal part forces seems more annealed. Expanding areas such as anything spherical still suck, but better. I do not believe the material itself of precision model is some super mega special sauce, I think perhaps this gives more credibility to fixing all other materials to print settings. Obviously, only printing in precision model is not a long term solution and I would really like to get back to using Tough 1500/ any other general purpose material and expand into biomed stuff without worrying about 1st print reliability. I implore Formlabs to investigate this further and hopefully come to a quick solution. This gives me hope however and I will be keeping the machine for now.

[leonhart88]

Thanks for taking the time to write this up. There were some growing pains during the Form 3 launch and hopefully these are growing pains for the Form 4 that will get sorted out over time.

[verdugod]

Thanks for your in-depth feedback @eaglechen . Your reliability experience is definitely not what we expect to see for the Form 4. Our SLA product team would like to talk to you to better understand what’s happening and figure out how to improve your experience asap. If you’re up for it can you DM your email and I’ll connect you?

[dan_d]

As a company that’s seriously switching from a higher end resin printer to potentially multiple Form 4’s, it would be great to hear what sort of resolution there is to these problems.

[Catechxis]

Useful review, many thanks. I was hesitant of buying a 4B as I previously bought an Ulimaker S5 and then all my friends showed me better results on machines 1/10 of the price. So, I just did my first print on the 4b and surface wise it is good, but dimensionally warped and out of square. My Prusa SL1S gives much better results. Of course I am going to persevere and hoping this is just me getting use to the machine.

[eaglechen]

Update:

Met with the Formlabs SLA product team 2 days ago. They were incredibly professional and seem to listened to most of my feedback.

A large part of the discussion is the warping issue – I really appreciated the team’s willingness to work with me going forward, unfortunately, I was explicitly told that there is not a current concrete timeline to fix this warping issue.

I was informed Formlabs is in the preliminary stages of gathering information regarding this issue, and I was also told an estimation of this timeline is not currently possible either. I guess for now I will stick to only printing Precision model since all other material seems to exhibit this problem. Realistically, this feels like a major print settings overhaul is required and we are in for a long haul.

[kmcnultyform]

Hey @eaglechen – thanks for talking to us a few days ago. We appreciate your time and extensive feedback! As context for others, I’m Kyle and lead the SLA product team.

From our conversation, it sounds like you’re happy with most aspects of your Form 4: speed, hardware reliability, cartridge and dispense system, build volume, new materials, tank lifetime, sales and support. But you’re not happy with:

1. Warping on overhangs, expanding areas, and bottom corners/edges with Grey v5 and Tough 1500 resin. This issue was solved with Precision Model resin. But you understandably want the same performance with other resins. Your prints are succeeding but your voted print success rate is low because of warping.
2. Ease of support removal and touchtip size

Our team started looking into your warping issue right away – we’re currently collecting more examples and information. Today, Form 4 printers are reporting our highest print success rate ever, so we haven’t heard of many other customers with this issue. But we agree it’s important and are committed to finding a solution. We expect to solve it with new print settings in the next few months.

For supports, we’re continuously working on ways to improve support removal and supported surface quality. We should have a few different improvements here (software and print settings) over the next several months.

In terms of your other ideas/requests, we’re definitely thinking about a lot of them. A few updates:

1. Printer noise: the high power backlight requires a lot of cooling. We’re working on a firmware change later this year to make the fans quieter.
2. Arraying models: definitely interesting. But I haven’t seen many customers actually doing it successfully, even though some slicers have the feature. Let me know if you know people doing this regularly.
3. Tough materials with room temperature post cure: I see how this could be valuable for reducing temperature induced warping. Many of our customers have been looking for higher HDT, so our engineering resins have been focused towards higher post-cure temperatures. We’ll keep this in mind for future materials.
4. Long-term durable material: you mentioned long-term cyclic loading in indoor, ambient environments. Depending on the load, we see other customers having success with Flame Retardant, Rigid 4000, or Rigid 10K. Have you tried any of those? What competitor resins do you recommend here?

@Catechxis: I’d love to learn more about your prints on Form 4 vs Prusa SLS1. I just emailed you to discuss more.

[eaglechen]

Morning @kmcnultyform, again, I appreciate your time speaking with me. A lot of ideas are tossed around during the meeting, let’s summarize and put them into concrete, actionable items. Everything else is in all honestly, a nitpick. I ultimately don’t care if the printer is louder than a freight train if it makes me amazing parts. Let’s sort by timeline to make this easier:

1. SHORT TERM – focus here should be print settings. If this printer cannot actually print accurately or live up to a reasonably easy to use and reliable industrial process, Form 4 will not survive very long.
2. MEDIUM TERM – focus here should be immediate workflow, namely curing. These are large problems also somewhat carried over for Form 3. If you did not hear it from me, I guarantee other users will probably say this in the future. People will tolerate some experimentation, but they will eventually notice that their perfect print have to get tossed; this is obviously no good either. This step is even more crucial for printing like 3L sized things and finishing them accurately.
3. LONG TERM – perhaps better processes like arraying or better materials. Honestly, this is the least important, and this is the most personal opinion and honestly long term strategy for Formlabs. I am just pointing out competitor trends and what people want in terms of models since I am ultimately a service bureau. This falls into a nit pick.

Short term is simplest in terms of being very concrete but most crucial. I have nothing to say at it seems this issue is being worked on. However, of course it will remain to be seen whether a few months is 1-3 or 6-12:
A. Warping and overhang performance is issue #1, I will live with inferior support material if this is solved. Understandably wanting to print most of your material library reliably is a reasonable expectation.
B. That being said I lot of actually good industrial DLP competitors are moving towards thinner touchpoints and thinner lattice structures, probably saves material and easy to remove structure. I understand this will probably take longer to optimize.

Medium term – everything here is focused more or less during curing. I only briefly mentioned this during our meeting and I apologize if this idea did not get through, but ultimately I think we can both agree that it is really sad to see a good model finish but warp and get destroyed in the cure. Everything here is focused on getting an accurate cure, especially with engineering materials and things known to warp during curing:
A. A cure allowing one to hang the part off the plate and remain like the Form wash, except for curing may be desirable. This allows the support material (seemingly optimized for tension forces anyways) to remain taught and pull the model into a more accurate shape rather than turning into wet spaghetti and collapsing under a heavy part and warping the model. I would buy this, but of course I am for a still for the most part curing on supports. Testing probably required.
B. I mention low temperature curing, but the real point of this is accurate curing off-supports, maybe a stronger UV oven like fast cure but for all materials. If I can just blast like the engineering parts (even for a longer duration) without heat causing the green part to deform, allowing me to achieve similar properties but bypass the “danger” of having to actively heat up the green part actively and pray, I would but this even faster. Like I said before, a lot of competitive materials to Formlabs Tough and such utilize this cure process (no heat, strong UV only) already: * https://www.loctiteam.com/wp-content/uploads/2023/05/W00834.pdf ]]
I will mention that I have to orient even flat and normally easily printable things angled upwards and weld them down with supports to ensure they cure accurately, don’t remember if I mentioned this point. Obviously removing support post cure sucks more.

If the “short term” stuff can be solved, I would turn around and recommend the system. If the “medium term” stuff can be solved, this system would deliver the experience DLPs and SLAs 6-figure printer companies make for the most part for a fraction of the price.

Let’s talk my opinions of long term. Don’t obsess over these, these are nice to have but not super essential. Long term means long term:
A. I mention stacking, this is a mature idea; yes, it is niche and wastes material, however, DLPs from the 90’s and 2000’s do this already, I have seen 15+ year old stacks off an Envisiontec printer and things like materialize magics modules offer this capability too. I believe if Formlabs offer a version of this baked into Preform a lot of people will use it. I imagine your dentist friends will be very happy to print this at the end of the day:

B. I intend to use mSLA/ DLP or maybe SLS in the future to completely replace any kind of FDM. I think there needs to be one practical long term environmentally stable material where it can truly replace like an ABS/ASA thermoplastic outside or inside. I will eventually dip my tops into Formlabs Flame retardant, and I know rigid is good because they are more glass than resin, but they cannot take any impact. I don’t need it to be even as high performance like a nylon 12, just something as strong and impact resistant like reasonably good ASA plastic and environmentally stable. I don’t care if a little more work is involved, so long it’s not PU. Look at basically any of Carbon’s dual cure stuff or anything here: https://move.forward-am.com/hubfs/LFS%20Documentation/General/Printer%20Workflows/LFS_Stratasys_3d_printer_workflow.pdf?hsLang=en

Hopefully that clears some ideas up.

[leonhart88]

I can upvote the desire to eliminate or mitigate warping and deformation that occurs during post cures. I’ve found work arounds internally for myself, but agree that having a perfect part warp from post cure really sucks, especially when we’re delivering parts (eg. injection mold prototypes) to customers.

I have a friend who works with 3D Systems machines and he mentioned that none of the industrial grade machines or resins require a thermal cure to reach their maximum mechanical properties, so they don’t experience the same issues as Formlabs users.

A quick google showed this: https://support.3dsystems.com/s/article/figure-4-modular-material-curing-chart?language=en_US

Interesting how they actually specify at the end that parts can be submerged in a non-flammable liquid if “parts are getting too hot”.

[dan_d]

I appreciate the transparency here. It’s really nice to see a company proactively involved with their customers in a public facing forum and says a lot to your commitment to the product. Based on the details above, I do have a few questions/comments:

1. from what I gather, a lot of the problems that the OP was having were based primarily around Tough-1500 which you confirm does have some issues. I know you say Precision material solves these issues but what about Tough-2000? From a material properties perspective, we would ultimately like to print in an ABS-like resin which Tough-2000 appears to be.
2. In terms of recommendations for other resins to consider, have you guys looked at Loctite 3843? It’s their version of abs-like resin. It seems to have similar properties as the tough-2000. We’ve been using that for some time and like the properties a lot. It has been a little problematic for us to print but it’s hard to say whether that’s due to the printer we’re using or the material (we tend to believe it’s the former). FWIW, this material requires 60C while curing so it is not a room temp cure material either. We haven’t really experienced issues with warping post-cure but I cannot say whether that’s due to the material or cure chamber, or combination. But if it isn’t warped out of the printer, we have not seen it warp post-cure.
3. When we first purchased our DLP printer, part stacking was something we were quite interested in (being able to nest multiple parts and print many more in the z height) but in real use case scenarios, it isn’t very practical as it essentially ends up doubling your post process time. We have found for serial production of larger quantities of parts, it’s just easier and more effective to print multiple single layer trays than it is to stack them in layers on one tray. I can’t speak for everyone else but I suppose unless the parts where very flat with well defined edges, it just seems like stacking sounds good on paper only…

[eaglechen]

Not only does DLP systems like the figure 4 does this, the really big top down SLAs by 3D systems and Stratasys NEO does this. This is how they can print parts like this that are 2ft long AND have them come out mostly perfectly straight and dimensionally after post cure:

Materials such as the 3D systems proprietary stuff and basically anything by SOMOS requires only UV post cure in a strong light chamber, no active heating required. I saw a 1.5ft by 1.5ft architectural model with a thin flat base that looked literally perfect printed on one of these large SLA machines. The service bureau that did it confirmed they always remove supports before curing and touchpoints are brush away like 0.1mm. I would never even attempt to print something even near 1 ft long on the 3L (even the general purpose stuff can be finicky curing wise), it will pretty much guarantee to have dimensional accuracy issues, during printing or during curing.

Speaking of figure 4, its a competing top-down DLP system that can currently do this:

I don 't know what snake oil magic they sell, but it is capable of 0.1-0.3 (at least much smaller touch tips) and thin support structures. It also operates with this cure: https://support.3dsystems.com/s/article/figure-4-modular-figure-4-uv-curing-unit-350?language=en_US
Allow you to hang parts off the plate during the cure process. This solves a big frustration of parts collapsing the supports from weight and softening during curing. Of course, no active heating of parts during cure required.

I know I will not probably ever own a big top down SLA printer, they cost more than my house (if formlabs makes one that has high reliability, throughput and competitive cost I’ll buy it). But its not like Form 4 is winning a huge margin against some DLP competitors either. I was quoted 18K for a figure 4 standalone a while back I think (printer, wash, cure, etc.) This in reality is not that far from a Form 4B workflow (printer + 2 wash + CureL + service) over 15K already. We can talk running costs, but those are also kind of similar for Engineering materials too now.

[eaglechen]

Evening!

1. I had problems with EVERY general purpose material I tested warping (grey V5 and clear v5). Tough 1500 was worse. Tough 2000 has the most ABS like property, and is much stiffer than Tough 1500 with a little worst impact performance and ability to rebound. I can’t comment on how bad warping during printing is for tough 2000, I guess the only way to find out currently is buy a cartridge and hope… However, I will warn that tough 2000 has been most inconsistent in curing for me, requiring a 70C and 60 min cure like tough 1500. Thin walls and long sections are almost guaranteed to bend during the cure process. Formlabs knows this and discloses the material is not suitable for those geometries, I think you will have to experiment and your mileage may vary.
2. I would love to print the Loctite/Henkel or BASF resin library, they honestly have some material exceeding Formlabs engineering stuff on paper and can even be a lot cheaper with a little easier workflow. However, I don’t really want to fork over a couple thousand open material license and get back to like a desktop experience of writing material profiles on my own. I may as well get a desktop system (of which Loctitle and all those companies provide profiles for) at that point. Also, printers like Nexa, Stratasys Origin, and even Carbon all have profiles for these materials or have completely open modes by default. I might as well just buy one of those then… Furthermore, you can really tell that Form 4 or anything Formlabs machine is optimized to use the cartridge and resin dispensing system. I can’t self pour a resin bottle like Loctite into the Form 4 tank with anything more than like a 400mL print. I don’t know what extend of the open material license gets you, if it gives you like a cartridge you can fill and still have the printer dispense maybe this will work with a lot of effort. If Formlabs sells these material with a reasonable mark-up through their store and provides a fully integrated printing experience, I would buy it.

Also, I would guess the reason you did not see warping during curing for a lot of the Loctite and other materials even with a thermal cure is this: a lot of those materials have a green part heat deflection temperature higher than the cure temperature. A major weakness of a lot of Formlabs engineering materials is that they have a heat deflection temperature quite below curing temperature (for example tough 2000 cures at 70C and the green parts have a HDT of 35-40C), meaning the part will soften into butter during the cure process, causing things to warp or bend under weight of itself. This is part of why warping and curing is so inconsistent for the engineering materials.

3. I agree stacking is very very niche, but I do think if Formlabs can invest time into the texture engine, people would use stacking as well. I do actually print some very flat well defined edge parts, but it is nice to have this option for some overnight things because literally everyone else does this. Again, I can totally live without this, just pointing out market trends. Compared to ever other problem I have discussed, definitely small nitpick.

[leonhart88]

Not disagreeing with any of the comments above…but here are some things I’ve learned over the years to minimize distortion during post cure:

• Make sure parts dry for at least 24 hours - parts that are not fully dry of IPA are prone to warping more during post cure.
• I will often cure without heat for very large parts with thin walls and geometries. I will cure for 3X the time without heat. Anecdotally parts are definitely not the same as fully cured, but they feel somewhat in between green & cured specs on the datasheet.
• Curing with supports on can help in some instances, but I’ve found that the above two points are more useful for my process, so I always remove supports before curing now

Again, agree with everything above, but thought I would leave my findings here. Cheers.

[eaglechen]

Morning. Yes sir! We are on the same team, just trying to discuss how to make this product better. In this case, more so to get the product to do what the marketing says it will do… Fundamentally, I do not believe curing has really advanced beyond introducing the Form cure during the days of the Form 2 (afterall the design of the Form cure has not changed since launch). These tricks are pretty old and I have used them for years; these problems have persisted since Form 2,3, and was largely amplified by 3L. Form 4, of course, suffers from the same issues; better than 3L because the parts are smaller but I am starting to see the large parts off Form 4 being affected in similar ways.

Here are my findings that do corroborate your findings mostly but with some of my personal experiences as well:

1. Drying parts for 24 hours is not necessary unless the walls are really thin and the parts are very large (mostly stuff off the 3L like you said). However, adding a one day drying step obviously destroys any speed advantage of the Form 4. I know for sure a local client of mine will drop me and go to Protolabs or something if not for the overnight to 1-2 day turnaround I deliver. Fortunately, I don’t think the Form 4 parts are really big enough for this to matter and it is not necessary in my experience. All Form 4 failure for curing (mostly tough 1500) I have encountered are from some form of parts bending the supports and collapsing until their own weight in the heated cure for engineering materials, especially during a really heated cure where even small parts bend in on themselves from the heat., causing a dimensional accuracy issue so the parts no longer fit for the client. Leaving the prints out to dry 2 days do not seem to change this. Thinnish walls have mostly stayed straight for me, albeit usually with some clever supporting.
2. I have played with this up to a 5X duration cure cold cure, as well as stepping the temperature up by 10C at a time to avoid the part bending itself, but the end result is “somewhere between green cured specs and green specs” usually lands at the latter. I obviously do not have the resources to do the tensile and impact testing, but my experience seems to indicate the temperature is super important without a better light chamber. I experimented with this and given a similar part with full cure vs partial cure to a client engineer, the resulting full cure part in tough 1500 is fine while partial cured one was kind of green and unusable. At the end of the day, I do a lot of biocompatible with tough 1500 as well and I am supposed to follow this full guideline and cure for the skin contact safety as well. Clients also expect the full material property as claimed by the datasheet, I can’t really sell them something that is not that for what I do. Not being able to get out what Formlabs advertises for these materials would be disappointing.
3. My findings concur. New general purpose v5 accuracy do not seem affected by support removal followed by room temperature cure (but they warp right out of the printer…) precision model curing at only 35 degrees as well is accurate. Curing on supports is neccesary for the engineering materials with a high temperature above its HDT in green state, the supports are supposed to ensure the part doesn’t just collapse in on itself or some weird annealing forces bends the part. For tough 1500 and engineering materials, I never really got any success if I did not cure on supports.

I really think the critical weakness is the Formlabs engineering materials having HDTs in green and final state way below its curing temperature. Funny enough, here is an old whitepaper by Formlabs I followed while building a curing chamber when I used Form 2, careful to avoid curing parts above its HDT to avoid problems. Obvious, basically all Formlabs engineering materials now violate this: https://www.dynamism.com/download/2016/UV%20Postcure%20white%20paper.pdf

If we are struggling this much and are finding this even harder than baking a cake while pulling out every trick we have learned operating printers professionally to get this to barely work/ not really work well, I can only imagine what other users are finding out there in the field… I imagine the support team deals with this on a regular basis. I think people mostly expect part in cure, part out, which is completely reasonable, and this is not the case at all.

[Lantech50]

My personal opinion is that FormLabs should stick with the laser SLA Printers. This sets them apart from other SLA Printers on the market. With the Form 4, they are dipping their toes into the ever-growing MSLA Printer world, where many of the major competitors have several years of proven machines under their belts. For perspective, we have 2 of the Form 3+, and have recently setup a From 3L printer, and wash/cure stations. But when we begin looking for a MSLA printer (for print speed), there are several other brands that are substantially less costly, and put out great results.

[dan_d]

We have internally questioned whether it’s MSLA technology in general that’s more finicky than SLA in general. Coming from a machine that cost many thousands more than a Form 4, our experience with printing has been somewhat similar in ways to Eaglechen’s. But there’s also the question of hardware vs. software. For us, the hardware was problematic from day 1. Entire machine was replaced within 2 months of purchasing and the entire control module was swapped from the 2nd machine a few months later. We’re currently waiting on new LCD/light module since it tried to home itself through the screen a few weeks ago… This has been all within the course of 1 year. Needless to say the support (or lack thereof) we’ve gotten from this printer company has forced us to look elsewhere. But in fairness, we’ve talked to several other people who own multiple machines and swear by it and have had a completely different experience than us.

[leonhart88]

Yes agree with all of this. If parts are small enough to fit into a food dehydrator (or in my case, a filament dehydrator), I will throw them in there for accelerated drying.

This matters A LOT for dimensional accuracy of flexible resins like Elastic 50A (see here for my forum post about it).

100% agree though that improvements on post curing would probably give Formlabs a huge advantage over other machines…because most of the complains I hear from larger service bureaus are either support point sizes (hard to eliminate with inverted SLA) or poor accuracy (likely caused by post curing).

[leonhart88]

For all the limitations that we’re discussing, the Formlabs machines have been great to me. This includes the Form 2, Form 3, Form 3B, and Form 3L.

I have heard from a few others who share experiences similar to yours though, but relatively unclear as to why they had such a different experience.

[LEADNAV]

Great review, keep at it and keep us updated on the forum. Been waiting months on an honest review.

It took me nearly a year bringing up software issues with the Fuse 1 before Formlabs finally acknowledged and fixed the majority of the issues within the software. I know what it feels like to be a “beta tester”.

After reading through this thread… I will gladly be staying away from Resin printers in general, but wish you luck.

[eaglechen]

Morning @LEADNAV !

Ironically or perhaps not, I was talking to sales a couple months ago and was very close to pulling the trigger on a Fuse 1 system. I think your thread and what everyone has said on the forums is the reason I have not done this. I reallyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy do not want to be 35k-50k in the hole and then playing with thermal offsets and praying my $700 chamber of parts do not turn into a solid brick or warp while clients are breathing down my neck for prints.

I am very lucky this is only a small part of what I do, my organization has both a service bureau and a non-profit side. The goal is to net zero, and we are… not doing that. We are in the red, by quite a bit. I have already told one of my clients to go just use Protolabs or something due to the fact I just cannot print anything other than Precision model accurately (which is not perfect either). Ironically, ordering parts from very large service bureaus is not that much more expensive than what I have to realistically charge these days. Turns out large service bureaus with 250K SLAs can do a first print success and ship those over volume and consistently make money, unlike me…

I am unsure who is out there consistently making money and actually having success with a Formlabs SLA system, if not for the personal relationships I have with some of my clients, they would have long told me to go fly a kite. Service bureau is the perhaps the best test of a system’s maturity, I see all kinds of parts and print everything with high reliance on a printer’s performance due to client expectations. So far, all factors point to this system being not mature.

Fortunately, on paper Formlabs seems to promise a fix with a several months turnaround, but the large scope of all the resins that do not work makes me question how realistic this all is. I guess time will tell. The largest reason I have not already dumped this printer is it is unfortunately the cheapest thing with a biomed workflow on the market. I have some future projects really depending on this, guess we will see how this will pan out. At the moment, I do not want to chuck a away $100 failed prints in one go just yet.