Substrate printing system

A substrate printing system, comprising:

• a perforated conveyor belt adapted for transporting a substrate to be printed, wherein the perforated conveyor belt comprises a set of perforations,
• a perforated grill which comprises a set of perforations and which is configured such that the perforated conveyor belt can be moved over the perforated grill, and
• a suction chamber in communication with the perforated conveyor belt and with the perforated grill such that a suction flow created by the suction chamber is adapted for passing through perforations of the perforated conveyor belt and of the perforated grill to secure the substrate to the perforated conveyor belt,
• wherein:
• the perforations of the perforated grill have a different pattern in a first area adapted for printing substrates than in a second area not adapted for printing substrates;
• the perforations of the perforated grill are configured to produce greater blocking of the suction flow through said perforations in the first area adapted for printing substrates than in the second area not adapted for printing substrates;
• and
• the perforated grill is removable in the first area adapted for printing substrates with respect to the second area not adapted for printing substrates;
• wherein the substrate printing system further comprises:
• a blocking means adapted to at least partially block the suction flow through perforations to a different extent in the first area adapted for printing substrates than in the second area not adapted for printing substrates.