Fighting with computers

One of my current projects requires to run two, maybe more in the near future, DIY CNC machines. Machine controller is USB-based and a PC could be used to send g-code to machine controller. However, we have tried a different approach that proved successful: using a cheap tablet instead of a PC. It all started by testing the excellent program GCodePrintr by Mathias Dietz. This software is designed so people can use a 3D printer directly from a tablet. You can stream a g-code file for printing to the printer plus you can do all the usual manual functions of moving the axis around. Besides, a graphical simulation of the print is represented on the display. And in the few tests I did, printing speed did not seemed to be compromised because the lower tablet performance (compared to a PC). However, uploading a file from Dropbox or using some FTP app for sending g-code files to the tablet was not very convenient as required user time spent at the tablet. But one feature of GCodePrintr

I needed for a project some metal holder plates for nema 23 motors. As I have in the lab a Chinese 6040Z CNC router I thought it will be an easy thing to do. Oh boy, how wrong I was. They project was a simple plate (very easy to sketch using OnShape ). Once it was sketched a 3D part could be created by simply extruding it, which may come in handy if some drawing assembly needs to be done for documentation purposes. However, for 2D projects a 3D model of the part is not really needed for the process of creating 2D machining code. There are different solutions out there that are free, but one that I like because it is very simple to use and it is on-line is makercam.com but for that you will need an SVG file instead of the DXF that OnShape can easily produce.  I usually use Inkscape software for converting to and from SVG and DXF. I did so in this case and it worked as expected. So, once I have got the SVG file I can feed Makercam.com I need not to forget to chang