Flow rate

[dirk8037 0]

Hi,
I am using Cure (now 4.13.1) for quite a while with an Ender 3 (updated with a silent board). It workes fine in general.
I now spet some time to calibrate the machine and am struggeling with the fow rate.
After the e steps an Z offset were done, I could not get the wall thickness of the test cube below 0.45 even I pushed the Flow rate down to 80%.

100% was ca. 0.47 with +/- 0.01-2 on the square side compared to the length side (which was strange too)

Seeting was Layer Hight 0.2 Wall thickness 0.4 by 50mm/s, Noozle 200C with PLA,
Extruder and 0.4 noozle are from Micro Swiss.
The result is good, layers sticking nicley, no under or over extrusion. Though I wondered that nothing seems to change.
 

I started to search and found here info that its seems to work via the E parameter in the G code and not via the M Parameter at the start.
So I created to files one with 100% and one with 80% and compared the code - it seemed absolutely similar.

The Max factor was not set.

 

Did I miss something?

Are there maybe other parameters (Marlin?) that are interfering with the Flow rate?
Did I understand it right, that theoretically the Flow rate change is like a print based eStep mod.
For some reason I had to push the them, based on teh measuring to 135.
Maybe thats equilizing the whole thing.

Thanks for Help
Dirk

 

CE3_Test Cube 20mm 0,4 mm Wand v2_80.gcode CE3_Test Cube 20mm 0,4 mm Wand v2_100.gcode

Edited March 15 by dirk8037

[GregValiant 695]

I see you haven't read my rant regarding single and double wall calibration cubes.

In the Marketplace you will find a plugin called Printer Settings.  Load it and restart Cura.  One of the settings in there is Diameter.  Measure your filament diameter with a decent caliper and enter the number into Cura in that box.  (My filament from Matter Hacker is a very consistent 1.72 diameter and not 1.75).  Calibrate the E-steps of the printer and you are all done.  The prints will show you if you are over or under extruding.  Ya just gotta look.

 

Walls are not a particularly good check of over-under extruding.  Infill and skins give a much better visual.

 

Flow is the ratio of:  Volume of Filament to Volume of Extrusion.  When that ratio is 1:1 the flow is 100%.  The thickness of a wall that consists of extrusions that are unconstrained on both sides just doesn't come into it.