Update README.md

eagle/README.md

@@ -5,6 +5,12 @@ To get this script to run, use the following steps:
 * Save eagle_png.py into the folder where you keep your .brd and .sch files
 * Install [ImageMagick](https://www.imagemagick.org/script/index.php)
 * Create a polygon over your .brd design on the Milling layer (number 46)
+* Set the isolate value for the polygon to a number greater than 16, this will ensure there's enough black space for mods to generate toolpaths in (see image below)
 * Save your .brd file and close Eagle
 * Run eagle_png using the following command `python eagle_png.py board_folder/board_name.brd`
 * The script should have saved several .png files into the folder where the .brd file is
+
+<img src="img/isloate.png" alt="Increase isolate value for polygon" width="700"/>
+
+
+