Making a groove on the surface


I want to make a groove on the surface . I created guideline surfaces ( green surface on layer “01”) to make grooves on the rhino object( layer “Helmet”). I don’t want the groove going all the way through the surface of the object. I want pretty shallow groove (~ 1 mm deep) at the position of guideline surfaces so that the 3D printed object has those lines like hexagonal pattern on the soccer ball.

To begin with, I tried Boolean difference (though it produces through grooves which I don’t want) , it did not work. Any suggestions would be appreciated.
32ch_Ospace (13.0 MB)

Hello - keep in mind that surfaces have zero thickness - you’ll need to create solid objects that have volume to make your cuts. You can try OffsetSrf > Solid=Yes as a start. Distance of .1 or .2. It looks like you’ll have to make your ‘fins’ not quite so deep as to go fully through the pink shell.