Cartridge sensor wildly inaccurate

The Form 3 used to be relatively good at detecting how much resin was left in a cartridge. Maybe it would estimate about 10% more than there really was in there, but recently I’ve noticed all three of my printers are way off in calculating the levels. I have two here that estimate about 90% full, but they’re virtually bone dry.
Is there a fix for this? I see there is a maintenance option for Resin Level Calibration but that seems to be to do with underfilling or overfilling the tank? Or will doing that solve the cartridge sensor issue as a side effect?

Yeah. My last resin cartridge ran dry, and the printer still thinks it’s half full.


Though it’s not like this is the only wildly inaccurate metric. Print times are also abysmally accurate.

My printer insists the resin tank is also well past it’s best-if-used-by date, but the tank continues to work just fine in spite of it. I think I’m pushing close to 300 days past its “limit”. Though in this case, I can’t really complain.


Same problem for me.
I launched a long print and it stopped right in the middle of it with an empty cartridge error.

There’s no way to know in advance if a print can be completed with an indicator that inaccurate…
An update would be welcome to fix this issue.

Hey everyone!

Thanks for your continued feedback on this issue. Resin metrics are something that we’re always looking to improve and that we will continue to work on going forward. That being said, if you feel that your estimates are wildly inaccurate or unusable, I would recommend reaching out to our support team. They’ll be happy to investigate your specific issue further!

It’s also important to note that the “Resin Level Calibration” option is for calibrating the sensor that measures resin levels inside the tank. As such, it will not affect estimations regarding the amount of resin remaining in a cartridge. Hope that helps!

I’m having the same issue. I’m actually baffled at how ridiculously inaccurate this is. 700ml left but the cartridge is actually totally empty. If the basic grey resin costs 150 usd then I at least expect to know how much resin is left inside the cartridge because it’s impossible to tell without outright weighing it. I’m pretty pissed about this with all things considered. My expectations were very high with this printer and I keep finding new things about it that just continue to weight down on me.

thanks for the awesome information.

I’ve started doing the math by hand. Preform tells you how much resin the print will consume. I add that up over time. I think my estimates are coming out quite a bit more accurate than the Printer’s estimate…

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@plastermatthew You’re lucky that your printer will over-estimate the available resin. My printer has the same bug but in the opposite direction. I have a roughly 30% full cartridge but it thinks it already used up 2.1L out of the available 1L :sweat_smile:

Now I get 2 warnings before every print and then a “Sensing Resin” in-between any two layers, so a 3h print job takes 7+ hours :roll_eyes:

thanks my issue has been fixed.

This is a recurring issue for me as well. A work project is stalled out for a few days now because the cartridge incorrectly showed 39% remaining when it’s bone dry. Very frustrating for an otherwise incredible and easy to use product.

@formlabsteam - When is a fix coming? The current cartridges estimates are sadly unusable with the current setup. Can you at the least release a software update to use the material used each print for better accuracy, like @Randy_Cohen mentioned?
Also, while initializing the print, the printer should tell me when a print won’t have enough material.

Temporary solution - pull cartridge from machine and feel how heavy it is to get at least some idea of how much resin you have left… I think I remember someone who was weighing full cartridges to compare to empty to figure out the density of the resin so they could use the weight of a partially filled cartridge to get a more accurate gauge of what was left.

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I thought there was a load cell on these printers that could be used to work out the resin remaining (and logically it should not be done between every 2 layers as someone reported above, just once at preparation stage)??