Dump question here: When the Form2 print says it’s low on resin, does it mean the cartridge is empty and only the resin in the resin tank is left, or does it mean there is still resin left in the cartridge.
If it’s the latter, when do I really know that the resin cartridge is empty?
It is the latter. It will give you another message when it is empty and stop the print and say something along the lines of “Cartridge is empty”. You have the option of cancelling the print, replacing the cartridge, or continuing and rely upon the leftover resin in the tank to be enough. You must leave the empty cartridge in the machine to run though.
Nice thanks for the info 
The printer only estimates what’s in the cartridge. It decides that the cartridge is empty by watching if the tank can be refilled. If it opens the valve a bunch and the tank doesn’t fill, it assumes the cartridge is empty. That’s not always the case, though. When there’s very little resin left in the cartridge, it doesn’t flow out at the same rate. The printer thinks nothing is coming out but a small dribble still is coming out. When the printer complains the tank is empty, I override it and watch the fill area at the back of the tank. When I don’t see any resin coming out, then I retire the tank. I doubt I’m saving more than a few mLs, though.
So basically, if I start a print and the cartridge is empty but the resin tank is full, it will let me know the cartridge is empty but still proceed with the print because the tank is filled?
Yes. And the tank holds something like 200mL so if the print job is less than that, the fact that the cartridge is empty won’t matter even if you don’t have a new cartridge. You just have to pay attention to the printer because it will complain a couple of times and if you’re not there to approve continuing, the print will be stopped until you do finally notice…
Thanks for the info