A brazilian jokes out there , and he had to make that one . <| sep |> From reading through your posts I can see that you ' re intelligent , but not as much as you ' d like to think . I ' d assume that you have a rather small circle jerk so your logic models have a rather short life span . No offence taken <| sep |> Short answer , cast saws don ' t have a spinning blade , they have a rapidly vibrating one . When that blade touches something with no give to it ie , the cast , it obliterates it because the structure of the cast can ' t move out of the way of the tiny teeth ramming into them over and over when it touches something pliable , like skin , the skin just vibrates right along with the blade . Not to say you couldn ' t manage to cut yourself with a cast saw , but you ' d really need to go out of your way to cause any serious damage It ' d be something like trying to cut yourself with the bristles of a comb . Edit On reloading , I see that uPMMEURPICKLE beat me to it but I feel my answer has enough difference to justify not deleting it .