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Does the 3L dispense resin sequentially?

My Right talk always runs down to empty while the left tank stays almost completely full. I’ve never let it just run because I don’t want a failed print. I end up swapping them when it starts complaining that one is running out. If I look inside the printer I can see where resin has dripped out of both tanks so Its not blocked, and the cartridge always works fine when I swap sides.

Both dispense at the same time but, depending on the cartridge, one may dispense more than the other.

hrmm, seems like there’s definitely something wrong with my Left dispenser then.

I noticed this as a well a while back and asked support. They told me that the 3L used to dispense from both cartridges simultaneously during a print, but the changed it a while back to only dispense from one cartridge until it is empty and then switch to another. The reasoning:

It is an alteration that will allow you to swap empty cartridges without the printer throwing a cartridge error and pausing the print.

After speaking with support yesterday I’m getting a different answer.

Under normal operation, both of these cartridges should dispense equally

Fascinating. As you can see I was told the opposite from support, shortly after the firmware update that made this change went live. So unless someone from FL decides to chime in on this thread, we’re left with… Who Knows?

Hi—the info @Steven_Hines was given is correct! This was a change in firmware 1.7.4 back in August. The intent is as he said, letting one cartridge run down ASAP and giving you as long as possible on the other, so that you can swap out the empty without needing to pause the print. (The only exception is the initial fill of a brand new tank, which will use both cartridges at once for maximum speed.) The person @FabDesigns spoke to was misinformed.

That said, @Eks is also partly correct that the dispense speed you’ll see can vary pretty noticeably. This is based mostly on the cartridge itself (the weight of the resin left in it speeding up the flow, viscosity changes from how much it’s been shaken/how much the resin has settled, etc.) and also a bit on the printer (there is some level of variability in printer dispense motors).


Oh thats great to know! We’ve had our machine since September so that’s the only behavior I’ve been familiar with. I had seen people stating they should empty at the same time which led me to believe ours was faulty. Also the rather ominous notification that states I may not have enough resin to finish a print even though It hadn’t used a drop of the left cartridge yet. I would be nice if it stated that it’ll switch over to the left one once the right empties out