The JGMaker Artist-D is an IDEX printer that is really, really neat. One issue I’ve run into is with duplication mode. Duplication mode works, but depending on how you send g-code to the printer you can get a very nasty grinding from the left extruder (T0).
I believe there is a bug in Marlin that needs to be addressed, however coming up with some simple start g-code, the issue can be avoided.
To best take advantage of this it is a good idea to create another printer in your slicing software. There are two advantages of doing this. First, you can keep the custom g-code for duplication assigned to that printer. Second, and this is a big plus, you can set the size of the print area to be just the left side of the printer. This lets you easily verify that the model you place on the bed will be within the printable area in duplication mode.
If you’re using Cura create another printer for the Artist-D. Name it something like “Artist-D Duplication”. You can then set all the settings the same but you do not need to select more than one extruder and the x-axis should only be 155mm.