Stencil printing machine and stencil printing drum

A stencil printing machine comprising:

• a printing drum including a cylindrical circumferential wall adapted to receive a perforated stencil sheet wrapped on an outer circumferential surface thereof and driven to rotate around a central axis thereof, said circumferential wall having an opening portion with many through holes formed therein, non-opening portions formed at opposite axial ends along the central axis of the printing drum to sandwich said opening portion therebetween, and at least one recessed portion formed in at least a part of said opening portion adjacent to said non-opening portions in an axial direction of said circumferential wall to thereby reduce rigidity of the opening portion adjacent to the non-opening portions;
• an ink supplying roller situated in said printing drum for supplying ink to an inner circumferential surface of said cylindrical circumferential wall of said printing drum;
• and
• a press roller situated adjacent to said printing drum and being urged against said outer circumferential surface of said cylindrical circumferential wall of said printing drum.