Hello,
Is there a way to force the printer to start a print instead of just sit there for eternity while it tries to fill the resin tank?
I am printing a very small part that will take a only a few ml of resin. My tank is almost full and cartridge is completely empty.
Rather the printer just say “Filing” is there a way to just tell it to ignore that the tank not completely full?
Sure, just fill in the resin from the cartridge directly…
(I mean take the cartridge and open it on the top side and let it flow in the vat…)
That easy sometimes 
Ah… if the vat is nearly full but cartridge is empty just take a chewing gum and fix the position of the level detector. Just take care that you have not a print that needs more then the vat fill…
I have found that if I wait, the print will eventually start. I haven’t timed it, but it takes a long time (probably at least 45 min). This is a big disadvantage to the way Formlabs has designed this printer. It potentially wastes resign if the user gives up and dumps the resin. There should be a user selectable override to immediately start a print with an empty cartridge.