Form 3 wants me to manually fill resin?

I’m super new to SLA printers and setting up my Form 3+ for the first time. Tank is loaded, resin cartridge loaded, latest firmware updated I sliced and uploaded 3D model. Now when I try to start print it’s asking me to manually fill tank to the fill line. I’m super confused, why can’t printer do it on it’s own? Is this step required? I read and watch some guides I could find and none of them mention manually filling tank… What am I doing wrong?

how very interesting i know folks have done this in the past but first time i have heard of the printer suggesting it…a new tank i assume?

Yes brand new. I assume I can skip it, but as this is my very first time using it, I though I’d ask :slight_smile:

You can skip it. It’s only letting you know that emptying a cartridge by hand on an empty tank will save you hours of filling.
On the 3L that trip has been there for ages and it’s a full cartridge instead of a portion of it.

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won’t that mess up the resin amount tracking?


It’s already messed up. Half cartridges report being empty and empty ones report being one quarter full.
I can’t remember the last time any printer got it right.


what I told them we should be doing is having a way of entering the weight of the cartridge before a print job and it knows how much is in the tray we should be able to get much closer to being accurate it would require us to weigh the cartridge though and enter a value on the printer or in preform

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Thanks everyone! Good point about resin tracking. I’m trying to fill it up “naturally” now. Been about hour and a half. It’s pouring very slowly and already gave me error and asked to check bite valve (which seem to be fine). I having hard time believing that I spent over $5K on this printer and all accessories (not to mention $150 on resin) and it basically can’t even dispense resin right…

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What bothers me even more is that this is the second generation printer of this design and it still is having problems that the 3 had and still happening on the 3+

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LOL I finally gave up and just poured resin manually. It’s printing now, yey!

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when having difficulty getting the resin to dispense the automated way, you may need to “re-slit” the rubber spout on the bottom of the cartridge.
DO NOT REMOVE IT. (or you’ll make a mess like I did)
carefully re-slit the rubber piece w/ an exacto blade

I would recommend against this. if you do manually fill it, the printer has no idea how much resin is left in the jug, meaning it won’t warn you before the jug empties.

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This was my understanding as well…but if preform or the printer itself is having us do this…does this indicate formlabs is throwing in the towel on this? rather than fixing it?

In a perfect world that would make sense but, after hundreds of cartridges used, I can say that the “estimation” is far from reality.

Even without manual filling, I get a lot of half filled cartridges reporting as empty and empty ones reporting as having lots of resin left.

I always check the weight of the cartdrige (lifting it a centimeter on the Form 3 and titling it with a finger on the 3L) if I’m unsure. Takes a few seconds and never failed me.

so I guess the moral of the story is double check the bite valve and if necessary make a slit with a razor knife then patience is required

No, just patience required. I have that message frequently and the bite valve always was fine. It is a bug in my opinion or rather poor product design.

I feel the same. Basically we bought into a closed garden and if you used a “regular” SLA printer before, that whole contraption about resin cartridges just seems like a system designed to grab money. I hope they remove these restrictions in the future at least in the software, even if it means it will void my warranty.or I would not be getting support anymore.

oh no doubt this is vendor lockin! - As both the trays not having removable fep sheets and the cartridges themselves being chipped…I assume the consumables are where they’re making their money from…They’re probably not even making their money on the printer hardware itself…would be my guess.

BTW something that occurred to me… I know it tracks my resin usage based on prints, so it should know when I’m running out, no?

The printer knows the volume of resin Preform calculates you have used. I knows nothing of the resin that is washed off prints, split or lost during filtering.

I still dont understand why filling is so problematic. the fill actions can just repeat and the ‘unable to dispense’ error messages avoided during tank initialization. Absolutely baffles me.

I’ve used many cartridges, only one needed the slit manually manipulated. All dispensed very small quantities at a time resulting in errors that I have to go in a push a button to resolve and the printer to keep trying.