for an connection between a blower and a burner i needed a sheet metal cone and decided to write a little inkscape extension that can do the calculating and drawing steps over and over again very fast

The extension unfolds a frustum (=truncated cone) or a cone (if cut diameter=0) and generates a sheet cutting layout or flat pattern projection
that can be rolled or bend up into a (truncated) cone shape. The source code can be viewed and downloaded from:
https://github.com/quirxi/SheetMetalCone/
Documentation can also be found here:
http://www.quirxi.net/code/python/sheet ... rview.html
If somebody finds a bug or has suggestions please contact me here.
regards,
quirxi