Abstract: A thermal printer for wide printing comprises a plurality of offset thermal print heads bearing against a rounded fixed anvil. The heads are mounted so that the active faces of each pair of successive heads form a dihedral angle in order to make tangential contact with the anvil along the active lines of heads. The printer includes a drum for driving the paper with the drum having a diameter which is greater than a predetermined value. Printing is controlled in response to a signal representative of paper advance as generated by an encoder driven by a wheel in tangential contact with the paper.