Hey, I am writing you, because I did not watch the video, did not read the text, can't comment there, still I'd expect for your waterjet cutting text that you include that fine sand particles inside the water are used for the real cutting, since they are an essential part of the waterjet cutter.
a follower of your physics collection
129143802s ago, by Antonio
I added you to my circles...you can comment from now on.
129143389s ago, by CorinaMarinescu