FlatCAM practical tutorial: gcode and PCB milling – Part 6

Finally, we are going to create a gcode for our machine.

Tools normalization

First, we “normalize” all tools and depth, open all geometry to transform in gcode, and set all tools to C1 so you can set depth to 0.07mm (or other depth if you prefer).

Join geometry

Another operation to get better readability of the project is to join the geometry with Edit --> Conversion --> Join Geo/Gerber/Exc -> Geo

Now I’m going to Join like so:

PCB_PCF8574_03_copperBottom.gbl_iso1 PCB_PCF8574_03_copperBottom.gbl_iso2	01-First2Passes
PCB_PCF8574_03_copperBottom.gbl_iso2	02-LastPass
PCB_PCF8574_03_copperBottom.gbl_iso3_ncc	03-RemoveIslands
PCB_PCF8574_03_logo.gbo_iso_paint PCB_PCF8574_03_label.gbo_iso_paint PCB_PCF8574_03_GND.gbo_iso_paint	04-Silkscreen
PCB_PCF8574_03_contour.gm1_cutout	05-Countour

Generate GCode

Now we will open all geometry files in sequence and click on Generate CNCJob object, but pay attention!!! You must select all Tools of Joined geometry to simplify. Click on the grid of tools and click “Crtl-A” first.

So now you have generated five gcode files:

• 01-First2Passes.nc
• 02-LastPass_cnc.nc
• 03-RemoveIslands_cnc.nc
• 04-SilkScreen.nc
• 05-Countour_cnc.nc

Drill gcode files

Now are missing only the gcode files to drill the PCB.

It would be best if you had bits like this.

You can find here AliExpress

Click on the excellon file and choose a group of tips to use; I usually use 0.8 mm and 1 mm. I use the 1mm tip above 9.5mm, then set the depth (Cut Z) to -1.9mm I select the first three tools in the table (below 9.5mm) and generate the GCode file.

So you can create two gcode files: one 0.8mm bit one for the 1mm bit.

• 06-Drill_08_Bit.txt_cnc.nc
• 07-Drill_09_Bit.txt_cnc.nc

Now we have covered all the milling parts, as you can see on the screen.

Mill the PCB

I started a tutorial on bCNC, and I used all these files as a demonstration; I began with probe and auto level and then all the milling files.

Final result

After cleaning It with sandpaper, the result is here. In this case, I use a 0.07mm depth, but when 0.07 is not sufficient, I raise the deep and redò the work.

Thanks

1. FlatCAM practical tutorial: introduction, installation and import
2. FlatCAM practical tutorial: copper traces geometry
3. FlatCAM practical tutorial: clean non copper area
4. FlatCAM practical tutorial: silkscreen geometry
5. FlatCAM practical tutorial: contour
6. FlatCAM practical tutorial: gcode and PCB milling

You can find Gerber, fritzing, images, and FlatCAM project files here.