Frage Estlcam and arduino

What do you mean with "setup the arduino with a USB-board"? There is no setup with, the arduino replaces the USB-board.

If you have a look at the first 3 pictures in the thread mentioned in my previous post, you can see the setup.
1. Spend some time to learn PCB milling and create the latest version of the shield ( find the files here )
The USB-board and WinPC NC will do the job.
2. Solder the parts
3. Remove the USB-board and attach the shield instead
4. Download EstlCAM and use it's programming function to write the EstlCAM "firmware" to the UNO
5. Plug the Arduino in to the shield

If you reprogram the Arduino while plugged in you should switch off all the switchable devices like spindle or vacuum, as they might start unintentionally in this case.

Thanks a lot for the links and the additional info. I will start trying in a few weeks when I have some more time. For now I am using the starter version of WINPCNC, which sort of works out for me.
The thing I have difficulty opening .plt files (which I conversed from .ai). It's a text I want to engrave, single lines letters, but somehow opens in WINPCNC with having outlines. But I guess this questions belongs to a different thread...

Or you can leave the electronics that are in Stepcraft in place, save a file in Estlcam and use either UCCNC or Mach3 to control the machine. Works perfectly well.
It's up to you if you want to take Arduino route so that you can mill directly from Estlcam, but having a lot more control in UCCNC or Mach3 - wins for me.

Well, that will not work.
Neither UCCNC nor Mach3 works together with the Stepcraft USB Port.
You could use these programs together with the UC100 controller.

Hi...I’m currently building my MPCNC with this setup.Uno and CNC Shield running grbl. I don’t plan on using the MPCNC for printing or running jobs from SD cards, so I think the Mega/Ramps setup is overkill for me.
I currently have everything moving. I’m getting limit switches setup and getting familiar with the CNC workflow. I hope to start cutting this weekend.
If you want any info on setting this up, take a look at the xcarve or shapeoko communities, as they primarily use an Uno running grbl.