"https://www.youtube.com/watch?v=3l6EcBg9EPA" [@24:30 - 25:10] He says something about the load of a threaded interface being on only one small part of the spiral. To me this seems a bit odd right?
How much contact area is there really between a screw and a nut? "Where is the contact point between screw spindle teeth and nut teeth?" - Here one answer suggests that it's dependant on the thread type and tolerances which makes sense, but I couldn't find any reference values in my machining books, besides this link which briefly mentions a contact area of 30-35% without further explaining it "https://fastfixtechnology.com/rail/the-benefits-of-lockbolts/"
Can you even talk about "contact area" or is it like with the teeth of gears more like a contact line?
Isn't the contact area almost 100% along the whole thread because of the elongation of the screw when torqued down correctly?
Why doesn't this value apear when calculating screws, as I would imagine it to be important when considering surface pressure between the two threaded parts(e.g. what material to use)?
I guess it's important to mention that I was thinking about machined threads not self tapping screws or something like that.