I’m posting the latest results, after disassembling the ShapeOko2 and reassembling it due to a change from one country to another.
A few things have changed:
1- I found an easy way to place and hold limit switches in the machine. See the pictures below for more info.
2 - The YetAnotherGCodeSender program was advanced and now it can be compiled in a Raspberry Pi and in a Mac. Probably on Linux too. The program uses a very crude text based interface and controls quite well the TinyG planner queue, sending commands to the controller only when it is able to process them;
3 - I installed a 808nm laser diode on the machine as I said I would. I tested it against black ink covered PCBs and it could remove the ink where the laser beam hit. Pictures below too;
4 - Instead of using a specific program for generating GCode from GERBER files, I decided to follow the following workflow:
a – Draw the board then export the layers to GERBER format;
b – Open gerbv, installed on a Mac through MacPorts, load the GERBER layer and export it to PNG;
c – Open MeshCAM, load the PNG layer, set the Z thickness to 0.1mm and set black to +Z. Follow the normal procedure and generate a toolpath only with the pencil pass. Save the G-Code to a file;
d – Send the GCode file to your CNC machine. I’ve used my own software here and made it translate the negative z movements to Laser ON and the positive ones to Laser OFF. Incredibly, it worked. The first result can be seen on the last picture below.