Hello All,

I know this question has been asked several times but the most recent thread I could find was back in 2011 and unsure about recent updates.  I have several rolled parts where the detail drawing is showing hole penetrations throughout it in the rolled state.  I'm aware of the fact that if holes are extrude cut into the rolled part, they will come out as ellipses in the flattened state, and vice versa if I put holes in the flat / unfolded state.  My question is this.  What is the best method to locate these holes if the drawing is showing holes located around the 360 degree circle (see below).  I tried using base flange under sheet metal to get the rolled piece, then create a new sketch to layout the hole locations.  I was hoping if I put sketch points on the rolled piece, then flattened it, that the sketch points would transfer to the piece in the flat, and therefore allow me to sketch circles and extrude cut, then roll back up.  But this won't work at the rolled piece will not show the sketch points when flattened.  Any suggestions would be great on the best approach!  I've attached the file but i only have it right now as an extrude thin, not a base flange sheet metal.  Thanks in advance!