Using Round Bar to Shave Your Drip Rails?

[Runupifudare]

I've been searching around and have decided to shave my drip rails. I've seen photos of people cutting, tacking, cutting, tacking...you get the picture. But I've also seen another post in which round bar was used and it gave it an even cleaner look but I can't find it again. Has anyone ever used round bar, and if so what size to shave thier drip rails?