The best suited datas for the production of stamping dies and engravings are the following file formats :

Vector graphics : converted to curves, with closed paths and without overlaps.
Saved in PC format as
. ai ( max. Adobe Illustrator version CS4)
. eps (max. Adobe Illustrator version CS4 )
. cdr (max. CorelDraw version X5)
or one of these formats packed in a PDF.

unsuitable are:
Vector graphics from CAD programs in file formats such as
. dwg, . dxf, . igs . stp are unsuitable, because they mostly contain 3D data, and if they were applied in 2D , the paths are not closed and built up of individual line segments.