Preform slicing speed

It’s not how large or how much area a print is taking or even how long it takes to print it. You can have a 5" cube, sliced at 0.025, and it will take a day to print, simply because there will be some 5000+ layers, yet the geometry is super simplistic, and the slicer should only take a minute or so to do the job and upload the model.

But then you give it a very complicated model with lots of discrete areas that need to be plotted, and you’ll see what the real performance is like.

It seems you have printed it on Form 1+, well I don’t have a Form 1+ to replicate it and I don’t want to try printing your idea of support in the first instance. There are perhaps better ways that will print faster when used with the form 2. As you are so reluctant to publish just the STL files there seems not a lot of point for me to put any further effort into this…

The files are readilly available from Thingiverse

But you obviously are unwilling to participate in the test I proposed. Whatever results you will end up with will not be representative of the proposed test.

Once again you missed the point of the test. It doesn’t matter what I printed it on, or with what profile. The idea was to give Preform a complex model to slice and see how long it takes it to do that one job, which would be measured by the amount of time it takes it to upload the job to the printer.

So enjoy the model but unless you’re willing to follow the given instruction you needn’t contribute any further.

Is the test you propose designed to test how well and efficiently the Form 2 will do the print (with its own support generation), or to test how well Dudemeister designed his own supports and how quickly Preform computes with a file built directly on the build platform?

So enjoy the model but unless you’re willing to follow the given instruction you needn’t contribute any further.

Dudemeister - Does anyone need your consent or permission to contribute to a thread? Perhaps you might consider not being quite so arrogant to other people posting on the forum, none of us are superior beings and as such a little respect and consideration to other posters might go a long way.

You state that you are involved with IT, but seem to ignore a huge variable in testing the speed of an upload. That variable Is the one of if that upload is via Wifi, Ethernet or USB, all of which will give significantly different results

True enough on the USB vs Ethernet vs WiFi issue. I hadn’t considered it since the Form 1+ only uses USB. So I suppose it’s via USB, which should be the fastest option (unless the Form 2 uses Gbit ethernet), although you’ll probably find that it won’t make much of a difference.

Withe respect to my comment to Dxxx, you’re right, it was condescending and beneath me so I appologize. It’s just that every time I posted something here and on other threads, he feels that he needs to take me to task and school me on the technology, terminology or just about anything that he feels he wants to argue or show his superior knowlede. Just take a look at the posts about GCode as an example.

Well, I am sorry you feel that way Dudemeister. I apologise if you feel my opinion and posts offended your superior knowledge, that was not the intention. This Forum is a great place to share, learn and to see other peoples ideas or issues. But - I must admit, the first reason that I come on this forum is to look at Formlabs products, rather than to find evaluations of alternative printers.

On a personal basis I think the Formlabs products are quite incredible on many levels, sure, I see problems, but overall its helped bring 3D printing to the masses.

I agree with you that Preform is perhaps not as fast as some of the slicing software used by other printers, but still think Preform is a nice piece of software that has helped bring laser based SLA printing to the masses. It does what in reality is an incredibly complex mathematical task very well.

With regards my posts about G-Code, In the 1990’s, a large part of my day job was developing and working on interfaces for converting CAD drawings (both 2D and very early 3D) Often these drawings were generated by hand( lofting’s) on polyester film, they were then digitised in a lofting’s shed and then converted to G-Code in order to create a cutter path (that was controlled by G-code) I think that gave me a reasonable understanding of G-codes. Let’s put this into perspective in terms of technology, the 8086 processor only became available in 1978, so technology was developing at a fantastic rate in the 90’s (and continues to develop at an even faster rate today) I can still remember seeing and using Autocad when it had a dos based command set…

Today I am lucky, I get to develop 3D printers and materials as my day job, so, Dudemeister, you can see its a little more than a hobby for me. Again, I think that gives me a little understanding of the process and technology, but I also know that there are a great number of people out there with greater knowledge than mine.

You know, if you would have stopped right after the third paragraph, I would have probably said that I agree with you that Preform is a great program (and I do believe it is), and left it at that.

But the rest of the post, is what I’m talking about. I don’t think I needed to know how you used to develop G-Code cutting paths from 2D and 3D drawings, and how much experience you have with 3D printers, in order to convince me and everyone reading these posts that you are right, and I’m clueless.

Oh, last but not least, “so technology was developing at a fantastic rate in the 90’s (and continues to develop at an even faster rate today”, that’s actually no longer true. Moore’s law is dead, and technological development in the silicon industry is slowing down, not getting faster.

There are more important and entertaining things in life than debating with you. I don’t intend to be drawn into a debate of if, or when Moore’s Law will end, I will agree that has slowed down and the collision of Moore’s law and Rocks Law is inevitable. That is just one aspect of the progression of technology. In reality overall advances in technology does continue to develop and certainly is at an incredible pace, lets be fair - ten years ago 3D printing was the exception, now its common place and is taking industry forward at an ever increasing pace. Its opened possibilities that 20 years ago were only dreams.

So an example of something that is more important than a debate with you is shown below - I hope you enjoy it as much as I have!


I down loaded the files and then loaded them into Preform. I set the resin profile to Grey version 4 25um layer height.

I used the auto configure button to add supports and orientate the prints.

It took less than 2 minutes to configure the supports and 4 minutes 12sec to upload to my printer via Wifi (so I would expect USB or Ethernet upload to be faster)


Dudemeister - to go back to your original post -( I have highlighted a few points)

I’m not sure what your point was going through this, as it’s not what I asked, but just so you know, the model you downloaded is actually at a smaller scale, the one I posted in Form format, was scaled up either 115% or 135% (I’m not home to verify this), as I needed it to match a specific scale.

Because the scale and orientation in your setup is completely different than mine, the support layout and density, number of layers and amount of time to print are different.

As I said before, not sure what the point of this was, but enjoy the model.

It would have perhaps been helpful to know that the scale was smaller, but the most important thing to notice is that its many more layers than yours, yet it took a fraction of the time you said to slice and upload. Did that not tell you anything?

I redid the exercise with the model scaled to 135%. Different orientation generated automatically this time, so now only 3342 layers but 16hr 15 min print time. This time the slice time and upload time was predictably even faster. It seems to demonstrate that when Preform is allowed to do its own support structure then its slice speed and upload speed are very similar (if not faster) than the speeds you gave using other software.

Just out of interest - what makes you think your orientation, support layout and density is better than the auto orientation generated by Preform?

The only thing I can think of is that the lower number layers in the print is going to give a faster print time overall - so I have messed around and was able to reduce the number of layers down (still with the model at 135% size) for speed I have gone for mini rafts (which I find work very well, and are easy to clean up from the model)

Slicing and upload times were even faster than before, so just why would it be better to use your support design?, it would seem that its possible to reduce the number of layers down by 506 layers less than yours. Faster print time, and an easier clean up with the mini rafts





This is what I got using PreForm 3.0.1 and Gray V3 profile at .025mm with the model downloaded from Dropbox.

Generating Print Files took approximately 3 minutes and 51 seconds.

Uploading Print took approximately 2 minutes and 25 seconds. (Over USB)

What was your CPU utilization during the slicing? According to Task Manager, PreForm was using around 44% for a minute or so, and then went to 90-96% for the remaining slicing.

EDIT: typo

@Dudemeister It took a 2017 Core i5 MacBook Pro with 16GB of ram about 20 minutes (maybe less, not timing carefully) with Preform 3.0.2 to slice and upload to a Form 2 over WiFi.

I suspect one wrinkle is that the underlying mesh could have a number of separate shells (looking at how the raft is conjoined-ish) which might be something PreForm doesn’t always deal with. If you take whatever you imported into PreForm (the output of Slicer or Cura?) and put that mesh into Meshmixer and Edit -> Separate shells, how many shells do you get? How many shells is that compared to other things you normally print?

After updating to PreForm 3.0.2:

Generating Print Files took approximately 4 minutes and 5 seconds.

Uploading Print took approximately 2 minutes and 9 seconds.

6 minutes and 14 seconds to slice and upload the print.

I have a 6700K with 16GB of RAM in my computer.

Hmmm. As I originally mentioned in my original post, I’m not using the latest Preform, rather I’m using 2.10.2, as all the new features that Formlabs has added to Preform since version 3 are exclusively for the the Form 2, and of no use to Form 1+ users.

When I send a print to the printer, it says “calculating…” for about 45 seconds or so, as it calculates the print time for the model, then it starts the upload. I don’t see anything that mentions that “print files” are being generated.

CPU load during slicing is 1-2%, as you can see from this screenshot, taken about 16 minutes into the process (I was trying to see if setting it to 0.05mm layers would make a difference. Yes it will , but only because there are only half as many layers).

I just tried installing 3.0.2, and while it installs, it simply won’t connect to my printer. It give me an “unavailable printer” error


I tried everything, I uninstalled the previous version of Preform, I also uninstalled and re-installed 3.0.2, rebooted a couple of times in between, unplugged and re-plugged the printer but no luck. I just keep getting the error above.

Is this compatible with Windows 7 Pro?

Update: I was able to install 2.19.3, and it too take a long time (about 28 minutes when sliced at 0.05mm

It looks like PreForm 3 is compatible with Windows 7 Pro, but it looks like PreForm 3 is not compatible with the Form 1/1+. It sounds like the error message could be a lot more helpful there (if not any less frustrating).
[ Clicking ‘requirements’ here: took me here: ]

My new hypothesis is that the slowness you’re seeing when slicing is actually related to the speed of the USB data transfer between the computer and your printer, and since your computer specs are so modern, it seems more likely that the bottleneck would be on the printer’s end there… especially with your CPU load staying as low as you report.

I was going to do an experiment and try to print to the virtual printer which should be fast, since it stores the sliced file onto the system hard disk (no actual upload), but I can’t figure out how to select the virtual printer.

I can select it when I start PreForm, but when it comes time send it to the printer, it only shows me the actual printer as an option to send the job to.