First, hero points for doing a text based screw description. Second, I assume that 100% of screws and bolts are created by cutting away - hard to imagine addin

First, hero points for doing a text based screw description. Second, I assume that 100% of screws and bolts are created by cutting away - hard to imagine adding something to the outside of a shaft. The only question is whether the resulting threads are raised above the shaft (screw)- by cutting away the shaft, or sunken below (bolt), by leaving the shaft in place and cutting in the threads. I realize there is nuance here - which is why I"m interested in seeing if I can find a screw (or bolt) that seems to break this pattern.