Brim Layer Height Formula

Dreide
Posts: 66
Joined: 07 Nov 2014, 15:23

Re: Brim Layer Height Formula

Post by Dreide »

inventabuild wrote:I'm trying to upload gcode and txt files and I'm getting a message that those files are not allowed. What kind of files does the administrator allow?
So far, I have seen .zip, .jpg, and .png attachments.
inventabuild
Posts: 271
Joined: 09 Nov 2014, 23:03

Re: Brim Layer Height Formula

Post by inventabuild »

Thanks, attached are to gcode files w/ only the beginning of the files saved because that's where I know settings exist. If more of either file is needed please let me know.
KISS - 2014-12-2 Dually Cooly 10.zip
(3.08 KiB) Downloaded 170 times
Cura - 2014-12-2 Dually Cooly 10.zip
(879 Bytes) Downloaded 165 times
Dreide
Posts: 66
Joined: 07 Nov 2014, 15:23

Re: Brim Layer Height Formula

Post by Dreide »

Well, in the Cura file there are basically no settings. And without having the code for even the first layer, not much can be said.
It seems like the first layer is printed at Z=0.3 with Cura vs. Z=0.38 with KISS. Even though KISS will extrude material for 0.38mm layer height, 0.38 is quite thick for an extrusion width of just 0.35. For a comparison with Cura more information would be needed.
Mikk36
Posts: 65
Joined: 08 Nov 2014, 14:46

Re: Brim Layer Height Formula

Post by Mikk36 »

For Cura, the settings are saved at the end of the file.
inventabuild
Posts: 271
Joined: 09 Nov 2014, 23:03

Re: Brim Layer Height Formula

Post by inventabuild »

Attached are new files...KISS w/ 0.3mm first layer height just like Cura and the whole Cura file so I don't leave anything out this time.
KISS 2 - 2014-12-2 Dually Cooly 10.zip
(4.29 KiB) Downloaded 159 times
Cura 2 - 2014-12-2 Dually Cooly 10.zip
(2.62 MiB) Downloaded 158 times
I appreciate any help you can offer...KISSlicer is still my favorite when I get the brim going again.
Dreide
Posts: 66
Joined: 07 Nov 2014, 15:23

Re: Brim Layer Height Formula

Post by Dreide »

In the KISS file the first layer is still missing, but anyway. The only difference between the Cura and KISS g-code seems to be extrusion width. In KISS, it is specified to be 0.35mm; with Cura, it turns out to be 0.44mm (=1.25 * nozzle diameter?).
Remains the question, why 0.44 is more effective than 0.35. On reason could be that for narrower extrusion widths, the nozzle interferes stronger with neighboring loops that have been extruded earlier and are cooled off already, so the nozzle might be somewhat more hindered in freely pushing down new filament. Another reason might be that a wider extrusion simply means more extruded volume per time, so the extruded thread has a higher capacity of keeping the heat and, thus, bonds better with the print bed surface. Still a bit surprising that it makes such a difference.
Anyway, if you set the extrusion width to 0.44 in KISS and still get a difference in brim bonding, then we really have to scratch our heads (in that case, please post the g-code and make sure that it really includes the first layer).
If the extrusion width really was the problem, then this speaks for a new KISSlicer feature which would allow for a different extrusion width for the brim or even the complete first layer (I think that has been asked for before).
inventabuild
Posts: 271
Joined: 09 Nov 2014, 23:03

Re: Brim Layer Height Formula

Post by inventabuild »

Thank you for taking a look. Where is Cura getting extrusion width 0.44? Below are Cura's extrusion settings from the Advanced and Basic tabs. Notice in the Advanced tab I have "Initial layer line width" set at 100% so I'm not trying to inflate it:

Also, would you mind showing the line where you see Cura w/ 0.44 mm extrusion width because when I searched up and down in the gcode opened in notepad I did not see that number?

Lastly, I attached a png of KISSlicer's Style tab settings and the whole gcode of a slice which I believe has the same settings as the previous one you were looking at.
Attachments
KISS Style Tab.PNG
KISS Style Tab.PNG (20.95 KiB) Viewed 4504 times
KISS 3 - 2014-12-2 Dually Cooly 10.zip
(3.46 MiB) Downloaded 149 times
Cura Advanced Settings - 1st Layer Line Width.PNG
Cura Advanced Settings - 1st Layer Line Width.PNG (14.89 KiB) Viewed 4504 times
Cura Basic Settings.PNG
Cura Basic Settings.PNG (16.2 KiB) Viewed 4504 times
Dreide
Posts: 66
Joined: 07 Nov 2014, 15:23

Re: Brim Layer Height Formula

Post by Dreide »

inventabuild wrote:Where is Cura getting extrusion width 0.44?
I don't know. I normally don't use Cura, so it was just a guess that Cura calculates it from the nozzle diameter. Note that there is also an Expert dialog (Ctrl-E, or via menu), but I could not find a default extrusion width parameter there either.
inventabuild wrote:Also, would you mind showing the line where you see Cura w/ 0.44 mm extrusion width because when I searched up and down in the gcode opened in notepad I did not see that number?
You just have to find the g-code for two parallel and adjacent loop segments and compare the coordinates. From that you get the loop-to-loop distance which should match the extrusion width. I use Repetier host which allows me to move the cursor through the g-code while seeing the current g-code line (or selection of lines) in a different color in the preview. It helps to limit the preview to the first layer ("Show single layer" with "first layer" = "last layer" = 2).
I also checked that the correct amount of material is extruded for a layer height x extrusion width of 0.3 x 0.44. For that you pick a long segment and compare the volume of that segment (based on its length) with the volume of the extruded filament (based on the differences of the E coordinates of the current and the previous segment).
inventabuild
Posts: 271
Joined: 09 Nov 2014, 23:03

Re: Brim Layer Height Formula

Post by inventabuild »

Dreide, you are a genius. I am using Lulzbot's version of Cura since I have a TAZ 4. You can find it here: http://devel.lulzbot.com/print_profiles ... medium.ini

You will see they have a variable "layer0_width_factor = 125".

I wonder if KISSlicer has a list of variables like this.
de_kaminski
Posts: 10
Joined: 28 Jul 2015, 15:35
Location: Berlin
Contact:

Re: Brim Layer Height Formula

Post by de_kaminski »

Ros wrote:For the BRIM Height, there's an option here..

Down Left corner "Brim Ht."
Image
What version is that?
Never seen those functions and names: Flow Gain, Pillar / Skirt /Wall etc. etc.
http://www.bigrep.com dekaminski@bigrep.com
Zmorph 2.0s BigRep One.2 KISSlicer Pro, Simplify 3D
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