Multiple times I’ve run out of resin when the materials library suggests I’ve got half a catridge or more remaining.
I recently had a print failure, leaving many “bits” in the tank, so I had to throw the whole tank and the resin in it away - a crying shame, as it was a brand new tank, filled from a brand new cartridge. I then filled a second tank from that same cartridge, performed a very small print, and the materials library shows that I have 980ml remaining, which is clearly compeltely nonsense as the cartridge is basically empty now.
It seems like all that it’s doing is subtracting the volume of resin used in a print, from the volume that’s in a cartridge. It’s not even trying to take any account of what’s in a tank / wasted / whatever. And there appears no way to manually adjust the values.
So as far as I’m concerned, the “Material in inventory” feature is utterly useless and actually somewhat dangerous, as it has led me to start large prints believing I have plenty resin left, and then I run out mid-print.
I’d be interested in hearing justifications / explanations from FormLabs on this.
Thank you for sharing your experience, and I’m sorry to hear that you had to discard a brand-new tank with resin inside. I hope you contacted our service team directly to report the issue and find out how they can assist you promptly.
We typically suggest two methods for cleaning a tank:
Resin Filtration: This process involves using a fine 190-micron mesh to filter resin, removing contamination and small particulates of partially cured resin. More details are available here: Resin Filtration.
I will pass your feedback along to the firmware team and ensure they are aware. The Form 4 includes a precise weight sensor below the cartridge floor, so that measurement should be accurate. If you are using a Form 3, please note that its cartridge “weight” detection relies solely on the amount of resin dispensed, which is calculated based on the cured resin per layer.
Basing it on the “cured resin per layer” is surely exactly the problem - I think that’s a misleading metric when there’s such a large amount of resin sat in the tank, etc - It’s guaranteeably wrong (300-500ml or something like that it seems to me) for every fresh tank. I’m sure you could make a much better calculation of remaining resin knowing that the tank is being filled from empty before printing.
This matters, because there’s no other way to know how much resin is left to print with – there’s no way to see what’s really left in the cartridge.
I watched the Form4 presentation/s, but hadn’t picked up the fact there was a new weight sensor to solve this issue - great stuff!