I have an Ooznest WorkBee CNC with a Duet controller, which is a stand alone board, mounted on the CNC and its controlled using a web based interface from a laptop in my case.
This works well for the machining of parts but is a bit cumbersome when setting the position of the cutter ready to probe for the zero start position, most commercial CNC systems come with a pendant that can be used to move the machine quickly to the require position, that's not standard with the WorkBee. I have seen youtube videos of a few different pendants that people have made and are sometimes sell, via facebook, I don't do facebook. They all appear to be £100+ and provide endless options above and beyond what I would like, then I stumbled across this video
Well I have use Arduino's for a few different things so set about building one. Mike had a switch that raised on lowered the tool to allow a dust hood to be fitted, I found that that function didn't work. There was a small error in the code, I fixed that but the decided I did not need that option but I used a macro to return the tool to above the x,y zero position so modified the code to do just that.
Here is my version.
I added a clip on the front of the machine so I had somewhere to park the pendant once I had finished the setup for the job.
And the best bit, it cost just under £25 to make.