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Form 3 Print Time Estimate Wildly Off


I am having similar problem. It seems that the time is either approximately correct, or wildly incorrect. It is never moderately incorrect. In other words, if I were to plot a histogram of actual/projected time, it would be a strongly bimodal distribution. It is either close to 1x, or close to 3-4x, and there are not cases around 1.5-2x.


having the same issue. I’m running production pieces and these wildly inaccurate time estimates are throwing off my whole schedule for the week. An hour ago my form3 said there was five minutes left on a print and it currently says there’s 2 minutes left. The print was supposed to be something like a 29 hour print, currently on hour 37. The same piece run on my form 2 only took 17 hours or so.


The machine’s time estimates are terrible. Not even worthy of consideration. I’ve yet to see a print come anywhere close. Ignoring the fact that the preheat time can be as much as 30 minutes and that’s not accounted for, it’s still terribly inaccurate. What I do is wait for the printer to print 10 layers. Most of which are base layers which take longer to print. Then I divide the total number of layers by 10 and multiply by however long the 10 layers took to print. This seems to provide a more accurate estimate for when the job will finish. But of course, you have to wait for it to start, first, to figure it out…

I think the laser effectively moves faster than the stepper drive moves, so the printer can cure in the Y direction faster than X (because the laser’s not running when the stepper is stepping, X motion is “dead time”). So if the print has an overall rectangular footprint, I think I get faster prints if I orient the longest dimension front to back vs. left to right. Fewer X steps makes for a faster print time.


I didn’t notice this problem before, but for the last week, I see the wrong estimation times for each of my prints. For example, when I start to print I see an estimated time of 8-9 hours, but as a result, I got in 11-12 hours.

I use Clear Resin, 100nm.
App version 3.15.3


All three of our Form 3’s have terrible estimations. Some of our printers even say there is only 8 mins left when it is on layer 8/300. The layer count is accurate but the time left is embarrassingly off and makes it impossible to schedule things. I will start a print thinking I have time for that one to finish and start another by EOD only to be extremely disappointed.


We are also having this problem. It’s very frustrating to not be able to plan around the printer and schedule prints. It completely throws off work flow when a print that as estimated to take 13 hours is now taking 20+ hours.

I can see this thread was started in November '19, it’s shocking that FormLabs have done so little to address this clearly significant issue since that time,


On the flip side, the last print I did said it would take about 13.5 hours and it took 14.


You’re getting there :slightly_smiling_face:
One of mine, for some odd reason, is always projecting more than it takes but only with Rigid 4000 in beta settings. I’m used to “it says 13 hours so it will be 15” and in this scenario I’m always getting on average 30~45 less printing time than it was projected. It’s like being in the last layer and saying it will still take 33 minutes so I guess that on that particular resin they’re over estimating in contrast to the others. Even today I set a Gray Pro print that would take around 6 hours (which would be the perfect timing for me) and it slipped to around 8 and a half hours.

I honestly don’t get why such a difference (above or below) because each layer has a set time that differs on the amount of laser being used per movement and the resin itself. Then the lifting and lowering of the build platform. That should be enough to be semi accurate but, the more layers you have, the more it slips.

The only thing that could make it slip would be the tank filling (for numerous reasons) but that’s a pre-print process.

Even if every printer is different (for whatever reason) and a tank may slow down more than others, getting the last print’s result in terms of speed should be considered for the next print. Like “usually takes xxx but this printer sucks and takes 1.32 times more so let’s reflect that” or something.


Hey everyone,

Thank you for your thoughts on this issue, and I’m sorry for the frustration!

Print time estimates are something we’re always looking to improve and that we are continuing to work on. That being said, if your estimates are extremely off, I would recommend reaching out to our support team. They’ll be happy to investigate your specific case further!