calibration s3d and volumetric feature of a firmware

[arhi]

having some weird situation that I don't properly understand.

initially my firmware (smoothieware) was incorrectly set ('cause of a typo) to not use volumetric E .. I calibrated s3d with such wrongly configured firmware and I was getting good results (very precise). then I moved to use 3 other slicers and I had problem there (on all three) that I was getting way too much plastic out with "normal" settings and trying to figure out what was wrong I found out my smoothieboard was not using volumetric at all (filament diameter was set to 0)...

I reconfigured smoothieware properly to know that filament is 1.75, nozzle 0.4, proper steps per mm and with extruder multiplier set to 1.0 (in not s3d slicer, 3 of them) I was getting precisely printed parts .. (not as precise as with s3d but let's say properly calibrated parts, 0.400 mm was was 0.40x mm, 0.900mm wall was 0.90xmm I find that precise enough, but some things that s3d figured out some of them didn't so hole sizes were just bit too small etc..) ...

now I returned back to s3d 'cause while slic3r has great adaptive layer feature I need to print a precise part and I need support, and there's no better slicer attm then s3d for precise part and support... and well, as expected, my old profiles now don't work as now firmware has volumetric on... so I (without touching the firmware since I believe it works ok) started calibrating the s3d and I'm super confused ... I get proper wall thickness with extrusion multiplier 2.41 ?!?!

I need to fiddle with it bit more but this makes no sense to me ?!

g-code options
- 5d firmware (include e-dim) is on
- relative extr. dist. is off
- allow zeroing of extr. dist. is on
- use independent extruder axes is off --> maybe this is a problem? but this is a single extruder system so ..?
- include M101/102/103 is off
- firmware support sticky is off
- apply toolhead offsets is off

anyone have any ideas? the print looks ok with this 2.41 multiplier but I don't get why so high

[CompoundCarl]

Well if you print a very simple part like a single outline cube, you should be able to open the gcode file in a text editor and look at the E-values in the file. That will make it pretty easy to see if the software is asking for the right amount of extrusion per line. If that is correct, but the prints still look odd, then you might want to double check the firmware settings.

[arhi]

you should be able to open the gcode file in a text editor and look at the E-values

I did and it makes no sense that's why I posted here ... example:

Code: Select all

layer 0.2
width 0.5

s3d (with 2.41 multiplier):
G92 E0
G1 X80.750 Y70.250 Z9.980 E1.9538  ;
G1 X80.750 Y89.750 Z9.980 E3.9077  ; move 19.5mm extruding 1.9539 mm3
G1 X61.250 Y89.750 Z9.980 E5.8615
G1 X61.250 Y70.250 Z9.980 E7.8153

slic3r (with 1.1 multiplier):
G1 X61.250 Y89.750 E381.09678
G1 X61.250 Y70.250 E383.05766
G1 X80.750 Y70.250 E385.01854      ;
G1 X80.750 Y89.690 E386.97339      ; move 19.44mm extruding 1.95485 mm3

as you can see from the example both are sending more less same g-code but on slic3r extrusion multiplier is 1.1 and on s3d extrusion multiplier is 2.41 ?!?!

0.2mm layer 0.5mm width, assuming cuboid 0.2*0.5*19.5 = 1.95 and 0.2*0.5*19.44 = 1.944 so the value that's in g-code is good (not ideally calibrated, I can tweak that better in theory but this is more then good enough) ... now why does s3d take 2.41 multiplier to output this E value?? what am I configuring wrong ?! I'm 100% sure it's one of my settings that's making this misbehave as 2.41 multiplier can't be ok, it's compensating for some other error I made I just can't find where

[CompoundCarl]

Then you probably want to check anything else that affects the E-values like extrusion width, filament diameter, maybe even the extrusion override knob on the machine control panel.

[arhi]

MCP? why is MCP affecting g-code generation? That would be weird ... anyhow MCP is pretty general, everything is at 100% macro's are not set .. I doubt that's related ... to me it looks like the E value s3d is creating is not volumetric ..

I'm expecting to see extrusion of 1.95mm3 .. and s3d shoots E1.9538 -> E3.9077 = 1.9539 "something" .. now since factor is 2.41 s3d actually wanted to extrude 0.81 "something" .. since it knows filament dia is 1.75 (should not care really if the E value is in mm3) if I assume E is in mm extruded and not in mm3 what should be for volumetric then L=0.81mm and d=1.75mm gives V=1.949mm3 ... so looks like E s3d is shooting out is in mm and not mm3

Now the questions are
- does s3d support volumetric out at all (can s3d output E in mm3 value and not in mm)
- if it does support volumetric, how to turn it on

[brian442]

The S3D E-values aren't volumetric, it's in mm of filament. From looking at your factory file, you had the width set to 0.45mm, but your calculations you were using 0.5mm, so make sure to change that to 0.5mm.

If you set the extrusion multiplier in S3D back to 1.0, then you have a 0.5mm width, and 0.2mm layer height, and then I get these commands

G92 E0
G1 X80.750 Y70.250 Z9.980 E0.8107 F1500
G1 X80.750 Y89.750 Z9.980 E1.6214 F1500 ; this is the line we will use
G1 X61.250 Y89.750 Z9.980 E2.4321 F1500
G1 X61.250 Y70.250 Z9.980 E3.2429 F1500

So the E-change between the 2nd and 3rd line is 1.6214 - 0.8107 = 0.8107. Again, the E-values are in mm of filament, so that is telling your 1.75mm diameter filament to advance by 0.8107mm. So the volume of plastic you are pushing into the nozzle would be L*Area = L*pi*(d^2)/4 = 0.8107*pi*(1.75^2)/4 = 1.95 mm^3. We know this same line is traveling from Y=70.250 to Y=89.750, which as you said, is 19.5mm. So if we had to make a guess at the volume of the extruded plastic, we could do L*h*w = 19.5*0.2*0.5 = 1.95 mm^3. That's almost an exact match to the amount of plastic we pushed into the nozzle, so it looks like it's doing exactly what it should.

[arhi]

The S3D E-values aren't volumetric, it's in mm of filament

this is always so or? if this is always so and there's no way to tell s3d to go volumetric then the question is answered I just have to add to start script "M200 D0" to tell firmware I'm not sending volumetric but length data and everything is ok. I was just hoping s3d can send volumetric data too.. but not a biggie.

. From looking at your factory file, you had the width set to 0.45mm, but your calculations you were using 0.5mm, so make sure to change that to 0.5mm.

factory was uploaded when I posted a question, later when I was inspecting g-code I changed it to 0.5 for easier calculation

If you set the extrusion multiplier in S3D back to 1.0

it's all clear if it's not volumetric, as I said it initially was calibrated perfectly and then I moved to use other slicers for a while... so just turning of volumetrics in firmware will solve this, I was hoping there's a "flag" to let s3d spit out e values in volume not in length but it's really completely irrelevant if s3d or smoothieware are doing the length calculation so I'll just get the M200D0 to startup script to turn off volumetrics in firmware and I'm back on the horse again .... it just didn't strike me immediately that s3d is spitting out length not volume (should really, since the only thing that changed is that I fixed the typo in smoothie config effectively enabling volumetrics)