how to prepare cone by using roll bend

hai i am krish from india
i am an design engineer
but i am pretty new to this wildfire.
i am facing one problum while creating a circular cone using roll bend option in sheet metal. we can create the cone in several methods , but i want to make it using roll bending option only. so that we can reopen the sheet to know the original devolopment length.if u know that method pls write me. thanking u
krish

Edited by: krish_pro-e

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