STLs will line up automatically in Bambu Studio!
You only need about 2 layers of the artwork so scale the STLs to 0.4mm in height. The 3mf is for Bambu Studio or Orca Slicer. It has a 12x3 (12.25x2.8) negative cylinder and a pause gcode to insert magnets.
You have to scale the STLs in the slicer if you want them to be the same size. I accidentally paid no attention to the sizes when converting them. I scaled mine to 116.25mm in the Y axis to make them perler sized. Make sure you keep the Z scale the same at 4mm
The author marked this model as their own original creation.