In ISO world, none of them are usable for determining size. According to the ISO standard, the default method for determining size is the two-point method - unless otherwise stated on the drawing. This method does have it's own caveats though (see Neil's post) and might not be the "proper" method depending on the application.
In ISO world, none of them are usable for determining size. According to the ISO standard, the default method for determining size is the two-point method - unless otherwise stated on the drawing. This method does have it's own caveats though (see Neil's post) and might not be the "proper" method depending on the application.
