sheetmetal blends

I am trying to create a sheetmetal blend. I want to start with a circular shape and transition to a rectangular shape. (before you send me to the archives to see old posts on this subject, I have been there and not found the complete solution) have seen blends in the posts, but they did not look like the sheetmetal blends i find in air ducts. I can make the blend, but i cannot rip it or get it to flatten out for drawings and measurements. I understand that the rip needs a flat surface, I don't have one. are there any workarounds here? what do Professonal shops do? I could have done this on paper, I want to know how in Proe. I can't believe it is not possible, but have beat my head against the wall.


regards to all

can be the that it needs bend reliefs, that it doesnt have enought bends tomake transition from round to rect.,can be the way or order of your features, can be your accuracy or something else.why dont you just put up a file or picture? bythe way there a model in this forum in files