Form 2 vs Ultimaker 3: Material properties?

Hi, I am really interested in buying the Form 2 printer, because it seems to be very capable of printing tiny parts with a very high resolution, compared to the Ultimaker. I really need precision and acuracy. But may I ask:

Are there any drawbacks/cons considering the material properties (strengh, brittleness, etc.) compared to materials that can be printed with the ultimaker? I need strong materials for tiny mechanical parts (robotics). I think the “tough” material is well suited, but how does the ultimaker materials compare?


I haven’t tested any of the other resins beyond the standard resins which aren’t very strong for the most part.

Depends on what you mean by “tiny”. The Ultimaker (any FDM for that matter) is going to be bad for what I consider tiny feature rich parts so it will be more durable but you don’t get the surface finish or features you need. In general, the Form 2 materials are going to be more brittle than Ultimaker materials (think acrylic for Form 2 standard vs. Nylon for Ultimaker). However, I have been very happy with the Rigid material from FormLabs. It is brittle, but it is very strong so it is uncommon for me to break parts. I use Rigid for all of my tiny parts, 0.015" walls that flex a small amount during use, 0.030" diameter through-holes, 0.010" min walls surrounding those holes. A 0.035" thick wall feels robust out of the Rigid material for the small parts I do. Unfortunately, there is a backorder on the resin…

Tough is good per spec sheet, but I have found the detail isn’t quite as good as other materials and I don’t do my small parts out of it. Definitely worth a try, just depends on how small you need. See if FormLabs or another forum user can print some samples for you. In general, I will give the Form 2 a big thumbs up, we run it almost 24/7 for small mechanical parts. I can’t imagine engineering without it.

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FDM printers are AWFUL at small parts. they can not print to close tolerances when those tolerances are tight.
For prints larger than will fit in a Form 2, their course printing quality is more acceptable… but it is not unusual in small items for parts to be a full mm or more off dimension.

Also- the “strength” of their parts is over rated. Delamination - especially in the harder to print materials like ABS is a problem and perhaps their worst failing is their relatively low range of stable temperatures. Materials like PLA can not even stand ordinary sunlight on a warm day without warping and halving their strength.

Meanwhile- Form2’ s Rigid, Tough and Durable resins all compare pretty well to the best FDM can offer… but with far finer tolerances and surface finishes. Durable is a decent analog for nylon. Not quite as bullet proof but certainly usable for parts that will suffer mild abrasions or deflections.

what it comes down to is what you need from the printer.
for robotics applications, FDM DOES allow you to print in ABS and Nylon- albeit with less strength than properly injected or milled parts in those materials.

if you need to make larger structural members as well as small parts and can only afford one printer- then you might want to go with FDM- but a good quality printer capable of handling ABS and Nylon is gonna run you pretty close to what the Form2 costs.
It must have a full enclosure to achieve the temperature control required to print ABS and Nylon.

And- if you are going that route- you should opt for a machine with a dual extruder system- for 3 reasons… one- its not hard to design something that will take more than 1 kg of filament- and a dual extruder machine will enable you to pick up where the last spool left off with the second extruder- automatically. Second, because one of the biggest wastes in filament printing is how many partial rolls of filament that you end up with, that you can’t be sure have enough on them for the print you need to run… dual extruders allow you to put two partial rolls of the same filament on to make better use of each roll.
And third and most importantly- a dual extruder machine enables you to run DISSOLVABLE filament- so that you can print support structures that can be washed away- and makes possible higher quality and more complex prints.

( it can also print in different colors- but that is useless imho.- altho- it might be useful to be able to mix different filaments, such as ABS and flexible, to achieve hybrid properties. )

If you go for dual extruder- make sure its a machine that can Retract the extruder that is NOT in use- to prevent problems with the second nozzle striking the print.
I think Ulitmaker makes one- and the NEWER Raise 3D is also very well reviewed.

@PrintMan, if you are interested our numerical mechanical data, we have that available for download at the bottom of the page linked below.

To add to @Sculptingman’s comments, another drawback of FDM is that parts tend to be ansiostropic (i.e. have different properties depending on whether you load the material parallel or perpendicular to the layer lines).

Hi Im selling my formlab if you’re interested I just bought it about 5 - 6 months ago if you’re serious about buying contact me thanks

We have both an Ultimaker 3+ and Form2s at our work. We are often printing functional prototyping stuff that needs to be strong with good accuracy. A recent example would be some pulley gears. We printed the small motor pulley on the Form2 in tough and the much larger final-drive pulley on the ultimaker in ABS. I can’t comment on the life span of these gears as we haven’t hammered the pulleys yet, but they both seem like they will last pretty well for a prototype.
Tough and durable are the 2 engineering resins we really like for functional prototyping.

You won’t have delamination issues with the SLA prints and will have much better accuracy over small details. Part orientation and (usually) customising the support structure are needed to make sure your parts function as best as possible.

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I have used an Ultimaker 2 for several years, and in that time been able to reliably challenge the detail of resin, SLA and SLS printers. Certainly, even a 25 micron nozzle with melting plastic can’t beat a laser when it comes to the smallest details, but you can go VERY far with them.

As for tolerances- if you know how your plastic behaves and have a finely tuned machine, you can achieve great results, within a hundred microns or so.

In comparison, I’ve had my Form 2 for about two months. After having run about a few liters of Tough and Grey Standard resins, I am impressed by the detail it can capture, but simultaneously very underwhelmed by how horrendously bad some tolerances are in terms of warping. The Tough resin especially, which I need to be my go-to material due to the durability, is particularly bad for a material that targets “engineers” needing to make functional prototypes. And I know enough about print orientations and design aspects to lead me to suspect it’s either a flaw in my machine (support ticket incoming) or an inherent weakness of the process as it currently stands, that has been greatly underreported. I’ve had more warped and unaligned parts in 2 months of printing with the F2 that I had in 4 years of printing PLA with the Ultimaker!

As for durability- printing PLA correctly, you will not have issues with delamination of layers. PLA will beat the standard resins any day when it comes to durability- especially at thinner levels. (I’ve made hollow parts that can withstand the weight of a full grown adult.) The Tough however, does hold its own when it comes to strength. The weakest link when it comes to PLA is that thin parts will start to deform at around 60+ degrees Celsius.

I’m attaching a collage of parts, some of them showing high-precision parts. Most of them are FDM as the pile of Form 2 parts I have are not yet ready for photographing, but you can at least compare a couple of the same parts in FDM vs resin.

If cost is an issue, resins cost 10-20X more than the best PLA does. It’s expensive experimenting on a Formlabs machine!

In the end, I would say that if you are going to do super high-detail parts, need a VERY smooth surface without doing any post-processing (for painting), under 10cm in size, look at getting a Form printer. If you’re doing slightly larger mechanical parts that just need to function, look into a high-end (i.e. Ultimaker) FDM printer.COLLAGE|592x500

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I think the link for the collage is broken. I’m very interested in seeing the parts made with FDM.


Same here!

Depending on gear pitch, if they are fine you will have trouble with them meshing as that is a problem on all additive systems, same with screw threads.
In that case if you need precision gears you may be better off with a desktop cnc mill, preferably one with a tool changer.

FDM printers with fine nozzles can not even remotely approach the surface finish of the Form 2.
As to warpage… I think the OP’s issue is that he obviously has invested hundreds of hours and dozens of rolls of filament tweaking and massaging his slicer settings until he was able to correct for the most common issues afflicting FDM printers… But everything he thinks he knows about warpage and tolerances has no relevance with SLA printing. Its an entirely different animal with entirely different issues that require different approaches to correct.

Nearly All materials going from liquid to solid change dimension. So warpage is always an issue. Only Milling stock materials at controlled temperatures can effectively eliminate dimensional issues.

Even injection molding plastics requires correcting for the deformation of the specific materials being used.

Users with long practice clearly show that they learn how much to compensate for in trying to get a correct dimension… e.g. modeling a small hole slightly oversize to get a print with the correct dimension…

Learning design compensation for production means is standard practice.

And even then, milling can exhibit quite extreme deformations depending on the state of the material being worked. Warping with plastics is a huge issue and even steel or aluminium plates have to be relieved of internal stresses to be able to remove a lot of material without warping.

As for the choice between and FDM or SLA printer, it also depends on the experience one has with each technology. I am very happy to have chosen to use SLA over FDM for many reasons (material isotropy being a huge one), but I can see why someone with a huge experience in FDM would prefer an ultimaker. That being said, FDM printers are still in the “hobby/prosumer” category unless you go for those insanely priced Stratasys printers (which in the end have the same drawbacks as hobbyist-grade FDM machines), when the Form2 is definitely more in the “prosumer/professional” category.

Surprisingly enough, they can. It’ll never be AS good, but certainly a far cry better than “remotely approaching”. It does take knowing your machine (and it has to be a higher-end one, like the Ultimaker 2 or 3). In the collage image (I’ll try uploading again below), the black pistol (from Blade Runner) was printed to a surface finish that didn’t even need the usual filler-primers and things usually associated with painting FDM prints. Regular sanding light-moderate was all that was needed. That said, it wasn’t a fire-and-forget job. It was a challenge, just to see if it could be done.

Not sure if this was directed at me (as I’m not the OP), but it really didn’t take “hundreds” of hours nor “dozens” of rolls to achieve good results. Certainly, there was some experimentation, tweaking and learning, but it wasn’t too bad. (I would assume that already being familiar with traditional prototype-making processes, 3d modeling and designing for printing prior to using FDM also helped.)

And naturally, SLA is an entirely different beast. I don’t believe that I alluded to using the same methods in regards to orientation and such on the Form 2 as with FDM printing. Rather, I did a lot of research, months in advance as to the particulars of using the Form 2, before I decided to invest in one. (I almost didn’t, but the added detail capability was something I wanted, and I was convinced by the promise of needing to do a lot less post-processing before painting.) But the fact of the matter is that out of maybe 50-100 parts printed in the Tough resin, I don’t think a single one of them has come out without some issue, major to minor, with warping, mostly during the actual printing. As impressed as I am regarding some aspects of the F2, I have been equally disappointed in it, so far. We’ll see how it fares in the future.

Well, speaking for myself, I currently prefer the F2 over the UM2, despite having several years experience with the latter. But that’s mainly down to me being tired of the long, laborious post-processing needed for the stuff I mainly do- handheld movie props. (I’ve learned to hate wetsanding… yet ironically I spent half the weekend wetsanding Tough resin F2 parts!) I would also definitely say that the Ultimakers (2 and upward) definitely fall in the prosumer/professional category because they are regularly used by companies doing industrial prototyping and architectural modeling, as well as being at similar price points. (The latest UM costs more than the F2, but is, of course, a lot less expensive to run.)

I did not mean you spent hundreds of hour PER PRINT. I meant that getting those kinds of very good results from any FDM printer requires hundreds of hours experience working FDM printers… learning different filaments, and even different brands of materials.

It pretty much takes time to learn ANY technology to the point where you can genuinely control it.

you did not buy your first filament printer and your first roll of filament and get those results.

I’ve run filament printers- designed for them- but I just don’t have the time to invest in tinkering with one the way you have to to get the level of results you did, The Form2 let’s me click a button and get better results.

and I already have the hundreds of hours and prints experience with SLA to guide me.

Although I did recently get ahold of a vacuum forming machine for producing the larger scale parts I need to have superior structural strength.

I haven’t really tinkered with the FDM in ages. I got it pretty much dialed in so that I can basically hit print and go to bed. The only times it needs tinkering is if I ever swap to a new filament brand or type (which I don’t, I only ever use PLA and try to stick to one brand and color), when I clean it or when I need to make any small adjustment due to changes over time.

The “click a button” aspect is otherwise exactly why I bought the Form 2, but after close to three months, printing almost daily, using up several liters of resin trying different setups and models, I’m not getting anything near what I was expecting. The surface is (mostly) great, as is the fine detail, but when geometry, which isn’t really that extreme in terms of what it should be able to handle, keeps coming out of the machine bent, twisted or wobbly no matter how I orient it or how many supports I tweak or add… well, I’m not impressed by it, since the parts are unusable and have so far wasted hundreds of dollars. But I’m kind of starting to suspect there might be something going on with the machine itself, like perhaps it’s printing too hot.

The temperature of the resin doesn’t seem to have any effect. I’ve recently printed a batch which reached 45.5ºC which are undisguisable from batch printed at a lower temperature. However, there are subtle interactions between thickness, orientation, support placement and overall size which can affect the print. In general, I don’t get problems with warping, just gaps in the prints.

Yeah I noted a temp of around 45 degrees as well at one point. But if the temperature varies wildly at different points during a job, it stands to reason that it might affect the object. (At 45 degrees in Form Cure, you can deform Tough prints by clamping. I had to straighten several walls by clamping flat metal plates to them and baking them.) Most of the deformation I’m experiencing takes place nearer the build plate, at the beginning of the print, and it’s not the well-known “parallel to the build plate” problem. I’ll see if I can upload some photos later in another thread as not to derail this one!

For those interested, there’s a post in the support & troubleshooting section now showing the warping problems.

To the OP:
If you’re doing armatures and gears larger than maybe 3cm in diameter, need lightweight assemblies and a perfectly smooth surface direct from the machine isn’t a problem, an Ultimaker should work well, but if you need precision tolerances on really small gears and components (and maybe you want to model threading into the parts), maybe the Formlabs would be better. (Note however that my own experience with the F2 so far has yielded unsatisfactory results with “longer” models than around 8-10cm. I have not yet been able to solve the warping problem on those models.)