So I understand that this setting prevents clogs by not allowing overspeed of filament flow of certain filaments.
I see PLA has a higher value than generic PETG.
Has anyone tried to set an optimal value for a given filament? Is there a test or something?
Any info welcomed!
I am also interested in any good ways that someone might have.
This flow test allows you to find the maximum volumetric flow for a filament pretty easily:
https://www.printables.com/model/318350-bambu-slicer-max-flow-test-tower-for-x1c
Using Prusament PLA and PETG, I ended up with a maximum volumetric flow of 17mm³/s for PLA and 22mm³/s for PETG, so I don’t think PLA has always a higher value.
Thanks for the info.
Can you share your settings for Prusament PETG? That’s the one I am trying to fine tune.
Sure, here are the settings I came up with:
Thanks!
I was wondering how you’ve got Pressure Advance Stting shown 
. Guess is the softFever branch.
Did you find improvements without the automatic flow adjustment?
Yes, I determined flow and pressure advance by using the build in calibration menu of Softfever. I don’t use the automatic flow adjustment because I like to use the textured PEI sheet.
Thanks! By Any Chance you might have the profile data for Prusament ASA?
Sorry, but I never tried ASA at all.
Sounds like a good challenge.
Volumetric speed is kind of a master “speed limit” that lives in the filament profile, and by default this is the same profile regardless of nozzle size. You can change the speeds in the “process” profile as well, and you have more control over the “context” e.g. inner wall, outer wall, infill, etc.
Acceleration setting affect how quickly speed changes apply, when the printer is moving from one speed to another. Once the speed has reached a “steady state” the acceleration setting has no effect.
So if you want to increase the volumetric speed to some huge value, you will never “use” it at all, the other speed settings will kick in first. But I suggest you REALLY don’t want to do this; the max volumetric speed is your “friend” so that you don’t have to change the “process” level speed settings as much.
But using a test model to try to establish an “optimum” for this is misguided. It is easy to see the effect of changes in your print, just change to “speed” and you see colour coded by speed. If you keep lowering the max volumetric speed, you will eventually see that speed limit “kick in” and override the process level settings.
For example in a PETG print I am having problems with inner/outer walls printing “too fast”. I would first establish what speed works in my print by just changing it directly in the process settings. Then do “dial in” that setting for the PETG filament, I can choose to lower max volumetric. However you do it, the bottom line is you are changing the speed for a given trace of filament, which you can see graphically. If something is printing too fast, slow it down. Conversely, if your prints are perfect, dial in your speed settings. I like to check on what is the “bottleneck” in my print, and try to make improvements where they have the most impact.
“First layer” settings have very little impact on the overall print time, so “tweaking” them is unlikely to result in any substantial difference. However if the first layer has defects, you want to eliminate them because they impact overall print quality.
One thing I have noticed is that with a multiple filament print, Studio does not let me adjust the profiles independently, which is too bad.
I have just did max volumetric flow test on my new 0.4 nozzle and generic PLA filament using that model and I got no problem printing it upto 35.41 mmÂł/s 
I’m a little late to the party here, but figured I’d add this since I don’t see it represented.
volumetric speed mmÂł/s = print speed mm/s * Nozzle diameter mm * Layer height mm
So to figure out what value to plug into the max volumetric speed field, you read the suggested speed from the filament spool, and plug it into this formula.
For example, if my filament spool says 70 mm/s suggested speed and I’m printing with a .2mm layer height and .4mm nozzle diameter, then the max volumetric speed should be 5.6 mm³/s (.2 * .4 * 70)
That assumes extrusions are rectangular.
Simply download OrcaSlicer. Run the Max Volumetric Flow test, read the results and type them in.
valid point, that’s probably the most precise way.
The method I mentioned above is more for quick estimations if you’re in a hurry
I know this is almost 2 years past but will this same test work with the P1S?
Yep! Just download OrcaSlicer.
I tried 13 and it worked for Anycubic Kobra 3. I will try more later.
