Flat pattern of helix rod

Hello guys,

Tryed to search it, but didn't find.

Well we are using a lot of sheet metal for augers and I never had problems with their flat pattern.

But now we decided to test a auger made from rod, and I can't make flat patter for this. I attach the part.

I saw a lot of exampes to sketches merged with lofted bend, but this here doesnt work, because its a rod.

If someone could help me, would be cool....

Tomorrow i will try to use something like this with convert sheet metal:

YouTube 

SolidworksSheet Metal