I am new to CNC in general, found PixelCNC which had great reviews.  And didnt take very long to get my first GCode created.  I have stepped up the game one step and now I have an error which doesnt give me enough information to figure out what I am doing wrong.   Its in the Project Operations tab,  I am cutting machining 3mm deep holes for challenge coins to make a chess board.  I then want to use a tapered bit to cut a 0.5mm deep grid to more define each square.  The holes GCode works perfect, but the grid keeps giving me an error..   Any help is appreciated.  

Hi vzwjimdroid,

The situation is that operations which expect some kind of contour input require that there are closed shapes, with an inside and an outside. A grid comprising several crossing lines won't result in closed shapes that PixelCNC can use. The most immediate way to arrive at a grid of squares with where you're already at is to use the Stroke Paths function to generate a raster-layer from your existing paths-layer grid. Then use the resulting raster-layer as contour input for your Medial-Axis Carving operation with a Contour Z that yields what you're looking for on there.

Otherwise, you can draw a square paths-layer, and duplicate/merge, moving each duplicate to become neighboring squares. Just make sure you include a small margin between neighboring squares, at least as large as your canvas resolution will allow for. i.e. if your canvas resolution is 512ppi then you'll want neighboring squares to be 2.0/512 inches apart, so the contour that results from them doesn't merge into one big one.

Hope that helps! Let me know if you have any other questions or need help with anything else :]

 - Charlie