When using a nut, lock washer and bolt, should you also use a flat washer between the object and the lock washer? I have seen it done a million times that way but it seems the flat washer defeats the purpose of the lock washer. I assume the lock washer is there to dig in a bit to the object and the nut to keep it from loosening. The flat washer seems like it would allow the lock washer to rotate without digging in to the object.
Anyone know?