Hello to all

Yes these threads show information , but i had little confusion in technical reference manual , in example of closely spaced miter bend it is written spacing = 15.913 in . From where this value came?

Also in widely spaced example in same manual it is written Req = 45 in . From where this value came ?

How to specify spacing when Req is not given?
How to specify Req when Spacing is not given?