Hi Randy, if I understand correctly you say the vent cap needs to be closed because the cartridge empties itself otherwise due to the resins weight?
I’d say after the end of the print, the air pressure inside the cartridge above resin is equal to ambient, so if you close it the resin wouldn’t the valve drip until the air reaches enough under pressure to stop the dripping?
Really never happened to me
Did it to anyone?
It gets me thinking though about the creep in the valves rubber material. I haven’t cut a vent cap yet but if your cartridge stays upright it might become more relaxed overtime and be more prone to leaking.