Using a tablet to control a CNC machine

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I do have some CNC routers using Arduino Mega and Marlin as pulse generators and g-code interpreters. Usually they are connected to a computer for selecting and streaming g-code files to the machine.

Lately I was testing a new machine and I found an old Android tablet laying around, so I wondered if it could be used for the task of controlling the machine. I am aware of programs like Octoprint that can do exactly that using a RaspberryPi and I have seen it does a great job. However, unless some more hardware is added to the mix, no display or user input is possible. But a tablet already has the display and touch screen that can be used for that purpose, plus Wifi and Bluetooth for wireless communication. What was needed was a USB connection but for that a cheap OTG USB cable was all that I needed.

Well, once the hardware side is solved, you need some software and after checking and testing different options I ended up with GcodePrintr. A software that is designed for controlling a 3D printer that will do a nice graphical representation of the printing commands too.

The best thing is that though the program is not free, there is a version called GCodeSimulator that allows you to test your setup but will not send a g-code file to the printer (or CNC).

So I bought the program and it all seems to be working as expected even though the size of my "bed" is much larger than the graphical presentation allows, but that is not a big deal for me.

Have a look at some moves streamed from the tablet:


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