What Do Engineers Think of the Form 2?

I am a mechanical engineer and just ordered a Form 2. I plan to use it primarily for previewing designs that are headed for injection molding, among other things. I have a lot of experience with SLA parts so I know what is possible from the big guys. Now, I don’t expect the Form 2 to compete with a $50k printer, but I do expect it to be relatively accurate and reliable over its work envelope. Relatively being the key word. I don’t really know what to expect because there is not a lot of data out there regarding dimensional accuracy.

So, I would like to hear from other engineers that own a Form 2 and have put it to the test dimensionally. Anybody out there care to share their opinion? You’d think I would have asked this before I ordered, but I know this is as good as it gets at the desktop level. I know I made a good choice among other options.

Not a mechanical engineer, but I have a fair amount of mechanical engineering experience. Both my Form1+ and Form2 seem to be pretty accurate, within about 0.1mm in any dimension. But I’ve noticed a few posts in this forum from users with much larger dimensional errors.

I started with a FDM printer, which was lousy. And since I also own a CNC, I got in the habit of machining the surfaces I needed to be really accurate. All you need to do is a finishing pass, so machining time on a printed part is much less than hogging the part out of a billet.

And I’ve gotten better about designing for the capabilities of the printers, too, so I haven’t needed to machine any Form printer parts in a long time.

And both printers make really nice parts once you get a handle on their strengths and weaknesses…

I’m a computer engineer and I work in a Fab Lab environment. I had enough of our Makerbot 3D printers(Rep 2, Rep 2X & Z18) so I got my own Form 2 and it is waaay more accurate than anything I printed on FDM 3d printers. I make lots of prototypes that require accurate dimensional accuracy and as far as I can see, Form 2 has been delivering amazingly well.

It depends on how you wish to use the machine. If you’re printing mostly big parts with little detail then a regular FDM printer will do just fine. But, on the other hand, if you’re printing small pieces and you require high resolution and details then SLA will be your best friend.

I too have a CNC, and I have considered an FDM printer for years now, knowing I could do just what you described. I never took the plunge though, just felt that it was better to wait as I was mainly interested in precision. FDM just wasn’t good enough. Seeing proper SLA come to the desktop is very exciting. Both technologies have their place. I own a prototyping company and have always sourced 3D printing outside and kept CNC machining in-house. This will be a big shift for me. I’m thrilled to be able to offer this service directly.

I will probably buy an FDM printer too, as they definitely have their place, such as better engineering materials. Thankfully they are also less expensive. I’ll take advice on the best engineering FDM (no bells and whistles) if anybody has it.

My parts are typically 5" x 3" x 1", and loaded with detail. I have all kinds of inspection equipment so I’ll publish some dimensional data here once I get started. 0.1mm accuracy would be incredible. I don’t expect that though I was sent a dimensional study by someone at Formlabs that showed even better than that. Issue is, the study was on small parts. One part was a ring (tiny), and the other a dental print (medium sized). The deviation from model was color mapped volumetrically, and the numbers were impressive in the middle, worsening (still impressive) as you move out in volume.

I’ll provide dimensions in two dimensional form, on primitive geometrical shapes that are typical in an engineering world such as distance, flatness, straightness, circularity, true position, etc. This is the info I found to be elusive.

Anyway, I look forward to getting started and I hope to be a valuable contributor here in these forums. I’m a big fan of communication, and a believer in the power of a good community.



Hi I also have a CNC (4 axis VHF), I now use the form2 for Framework, I am waiting for the new castable which should be here in a few days.
I had a lot of dimension problems with the castable V1, but very good results with the clear resin ( despite I had to modify the Framework settings in my dental wings scanner).
I found the way to have a good burn out process and casting with the clear resin.
I have better results than with the CNC.
Just hope the new castable will be as precise as the clear…
I am very interested in your dimensional data.
I will be happy to share my settings if needed.


Fusion3 F400 if you have the funds.

A chinese Replicator2 clone if you are limited. Wanhao or FlashForge.

Fusion3 has awesome customer support and the Replicator style bots have a very widespread community and nice aftermarket support to print more exotic/engineering materials.

Open frame bots like the PrintrBot Metal Simple and Prusa i3 are well proven but will limit your material selection to PLA, PETG, and ABS with small parts.

First time I see the Fusion 3 but it looks awesome! It is well priced too vs other large 3D printers.

This is great. Thank you for the info.

Please let us know about your experience with the new castable resin, I’m interested in this for investment casting small mechanical parts in aluminum. I’ll explore this a bit down the road as I have a lot to learn about “simple” stuff first.


If you are thinking of a FDM machine, I would recommend you focus on Delta style machines, not the Replicator style of cartesian positioning. Deltas generally print larger and faster for the same money as cartesian. Deltas are also expandable (you can increase print height fairly easily). And provided you buy a decent machine, Deltas should produce better quality prints.

Also, make sure you know what materials you’re going to print with. ABS and some others really need to have heated printbed enclosures to prevent warping during printing. PLA doesn’t need heat, but it also doesn’t produce parts with the same strength as ABS.

I believe that Ford Motor company is quite happy with their Form2

Please do post your results! I have also had trouble finding solid data on dimensional accuracy for this machine. Looking forward to your future posts!

I am a P.E. mechanical engineer and my engineering company has a 3D Systems SLA machine and a factory full of CNC machines. We got a Form2 machine recently to save money on the outrageous price 3D Systems get for their resins. It take almost $1,000 to switch resin types on printer. We use the Form2 for small parts.

I am blown away by its surface finish. It is better than our 3D Systems unit, a highly regarded machine known for its surface finish and accuracy.

The Form2 is not as accurate as the 3D printer - it is out 0.040" over 6". Still pretty good for most of our work.

We use both printers for “touchy-feely” prototypes on occasion, but primarily we use them for casting patterns in limited production. We do steels, stainless steels, refractory and super alloys.

My only concern is reliability, but it has been fine so far. The fact that Formlabs has the various resins is a big benefit.

Bill Box

1 Like

Thanks everybody for your feedback. I will sit tight and wait for my Form 2 to arrive. I have an active project to put it to the test as soon as I get it. I’ll certainly report results here.

Thanks for sharing your experience! Good to know there are engineers getting use from the Form2. I haven’t placed an order yet, but maybe I will now.

Hi Bill, can you say in which direction you see the dimensional inaccuracy? Is it the Z-axis or the X/Y plane?

Also, are you building straight off the platform or from a support raft?



Your question makes me curious, is one way better for accuracy than the other, at least generally speaking?

Also, as I understand it, the effective size and shape of the laser “point” changes across the build platform due to the angle of the laser. Is this change compensated for by either hardware or software or is it just averaged. I have wondered this. Another way to put it, is the Form 2 more accurate in one location of the workspace than another?


Paul McGarr

Prepare for the worst, and quite possibly you will not be disappointed. The Form is not suitable for final approval of molded part design if you have any tolerance specified whatsoever.

I know this opinion may not be a popular opinion here, but I use mine for the exact purpose you describe…my crummy FDM is more accurate. Sure, the Form is more precise, but in a 3.5" part you might get 1/16" in variation between parts. One will be short, another will be long. Not just parts made on different days, but on parts made in the same batch, with the same alignment angle, they can easily vary 1/32"–and while 31 thou might not sound like much, if your parts must fit together, they are unusable. Even small postage-stamp-sized enclosures (smaller than a wrist watch) with 1mm walls are unpredictable as to whether they will fit together or not, often with 20 thou of variation. I usually print up about 3x as many as I need in the hope of mixing and matching to find sets, and even then, they require sloppy tolerances on the pcb.

I use the Form to see if things “look” right. For anything more, I still have to send them out to be printed on a “real” printer. Sure, it lets me reduce the number of prints I purchase, but that’s only very early on in the design phase.

CliffGriffin, are you talking from experience using the Form 1, Form 1+, and/or Form 2? Were the parts you printed all cured uniformly under the same conditions?

Yes, experience with the Form 1+, and we tried many curing methods, and did not find one that made the parts consistently sized, from an engineering design & tolerance perspective.

The Form 2 is so similar, I cannot imagine it being significantly different.