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Why is the tank filling operation so slow?


Today we installed a new Flexible 80A cartridge and tank in our ~4mo old Form 3. We are running into a ton of issues getting the tank to fill; we are multiple hours in and the operation has aborted or timed out multiple times. We have:

  • Shaken the new cartridge
  • Inspected the bite valve and verified it is fine
  • Verified that the vent cap is open and slightly unscrewed
  • Rebooted the printer
  • Run the resin level calibration routine

I realize that the system drizzles in resin relatively slowly and periodically rechecks the tank level. I just don’t understand why this process takes so long on a new tank, and can’t seem to find a consensus on what is common or expected. Can anyone here shed some light on this? It’s extremely frustrating and kills our workflow; we are 5 hours into getting a new tank set up for a print job that is only supposed to take a few hours total…

EDIT: we are running firmware version rc-1.13.3-679


While flexible and elastic resins can take a while to fill it’s far from 5 hours.
If the tank is a new one just drop a bit of resin directly from the cartridge onto it. Can’t recall exactly how much but you can do it in stages and check every time. While a bother at least it will let you go through that print.


Well, my last bottle of Durable didn’t flow at all. The bite valve appeared to be fine. I considered giving the cartridge a squeeze, but figured I’d end up squirting resin all over my workshop. Instead, I took a #11 Xacto knife blade and ran it into the slit in the valve (slit-wise orientation). Poked it in about 1/2 the length of the blade. Bite valve started to work as expected, including (much to my relief) still able to maintain a drip-free closed state…


Yeah, sometimes resin gets harder (kind of cured) on the bite valve and one needs to poke around. It’s an issue even with unused cartridges for some reason.
I had a few like that in different materials, no idea why.