So I have a setup with a CNC shield with 3 motors and plan on using GRBL. I'm very new to all of this but was wondering how I could power one of the vacuum suction cups on AliExpress with a relay chip while using this board.
For a cnc shield using a digital out, you would need a relay. There are many power relay options on the web for Arduino that would work, as long as the amperage is within range. Cheers Gary