I'm having a problem adding dimensions to a sheet metal flat pattern in a drawing. My part is a sheet metal cylinder that I made using the loft bend tool. I then extrude cut some holes through the cylinder wall while it was unflattened. When I make a drawing out of the flat pattern, SW will cannot create a reference dimension for the holes.
My assumption is that while the holes are round when the part is unflattened, they are not so round in the flat pattern. How can I make holes in a cylindrical sheet metal part that can will be treated as round in both the flattened and unflattened configurations?