I think this is the right forum

[DonRecardo]

I don't remember one in the past 1 1/2 years but thyat is no tto say that someone hasn't done what you are thinking about
But I think if I were wanting to reform copper wire from round to a "D" shape I would look for an older wire feed drive unit from a mig welder one of the industrial use size with 4 roller drive . machine the first 2 rollers to the diameter of the wire with 1 of them only slightly flattening the second pair would be shaped to the final contour of the desired shape and size. in any case if this is to be used as magnetic or electrical wire it will have to be re shellacked
If you are wanting to just re form the ends or short sections of wire then you would only need to make a pair of swedging dies one with a grove the desired diameter of the wire used about 60% in depth of the diameter the other only being flat

Thanks for replying, I wonder where it was I saw it ?
I want to make the D section to go around the edge of a model loco cab so
I will take your advice and make swage dies

Cheers
Don