Confirming all Cura settings make it to the printer

[nathanhogan 0]

I'm using Cura 4.8.0 and printing on an Ender 3 Pro.  I've looked online at various Ender 3 "best settings" and troubleshooting but I'm not sure Cura actually sends all the settings I tell it to.  I know when I adjust hot end and build plate temps that they change, because I can see that on the LCD. 

 

But there are so many other settings I can't confirm.  For example, I programmed the print speed slower on the first few layers and I can't tell a difference on the machine when it's printing.  I also told it to turn off cooling on the first layer, but the fan always runs.  Any suggestions on how I can confirm or otherwise enforce these settings?

 

Any help is appreciated.

[GregValiant 1,245]

Time to learn some Gcode.  The MarlinFW site has descriptions of the all the possible G and M commands.  Not all are enabled in your firmware.  Speed is "feedrate" in Gcode and is the "F" parameter in a G1 or G0 line and is in mm/minute.

 

Open the Gcode file in any text editor (like "Notepad").  I suggest you go through the Gcode line-by-line.  When you come across a command you don't know, go to the Marlin site and read the descriptions of both the command and it's parameters.  EX:  G28 is Auto-Home, G92 sets a location and appears often to re-set the Extruder location.

Many of the your settings in Cura are used in background calculations and aren't really numbers that will be expressed in the Gcode file.  Instead, what you will see in the Gcode is the result of those calculations.  If your initial layer speed is 25mm/sec then there will be lines like G1 F1500 X123.45 Y123.0 E1234.23456.  If your Print Speed is 50mm/sec then later you'll see lines with F3000 as the speed (50mm/sec * 60sec/minute).  If you adjust the feedrate using your LCD the numbers in the Gcode file don't change but the PrinterPlanner will make an adjustment to them on-the-fly.

 

The layer cooling blower is controlled by M106 and goes from 0 - 255.  In Cura (and on your LCD), it's expressed as a percentage of 255.  To make things more confusing either M106 S0 or M107 turns the fan off.  You will see one or the other at the end of the Gcode file when the print is finished.  The E values are expressed as "mm of filament" and are cumulative until about 4130mm and then they reset to 0 and start going up again (it's a math thing).

 

Sitting on your desk is a computer running Cura.  Over there on your workbench is your 3D printer.  The only thing that goes between them is the Gcode file.  That's why you need to have some understanding of what's in it and how it works.

Edited November 24, 2020 by GregValiant

[nathanhogan 0]

Thanks GregValiant, for pointing out the Marlin Gcode definitions.  The simple explanations you gave helped me figure out the syntax quickly.

[GregValiant 1,245]

Simple???

Damn...and here I was thinking I was being witty, clever, and confusing.