Hi all

I was wondering if anybody has a method of producing punch outs on a sheet metal part which can then be flat patterned for drawing views etc

By a punch out I mean a partially punched hole which is still attached to the sheet metal plate - which can then be forced or broken away by hitting or pushing by a third party......(hope this makes sense?).  See attached pictures...

Are there any tools / procedures in sheet metal which can create the punchouts and enable flat pattern

Have attached .sldprt for your pleasure ! and hopefully to show you the problem I am trying to overcome.

Any help would be greatfully recieved - many thanks,

Grahame