The logic on filling seems to close bite valve when mixer arm moves, then wait about 20 seconds before opening again. This leads to dispense errors (3 in a row) so doesn’t seem particularly optimal.
On a brand new form3 install, noticed glacial filling of tank with clear resin - the bite valve slit looked fine, just a tiny drizzle, even after heating up the cartridge to around 25C, and yes the vent cap was open
With next test with Tough 2000 I partly prefilled the tank (wasn’t sure what level exactly) which helped save about an hour off the fill time (after scoring the bite valve as it was completely shut and would not open with a squeeze!), but was still very slow as it continually stops filling!
It seems the mixer arm movement occurs around every 60 seconds, and the filling is stopped during this process for at least 20 seconds (it seems ages after the mixer arm stops moving before opening valve again), so we’re losing minutes of filling time (possibly up to 50% slower than it could be).
When the printer moves the mixing arm with resin in the tank, it will push the level sensor up so the printer will be able to know when there’s resin filling… but the stopping of filling closing the bite valve every time does not make sense at all.
I would suggest after two or three ‘dry mixer passes’ (where the level sensor doesn’t register), the printer should slow down the frequency of mixing AND not close the bite valve, to allow faster filling… This way the rate of fill can be crudely monitored and adjusted dynamically.