A hand welding extruder for welding plastic materials with a proximal end , a distal end and a central portion longitudinally extending between the proximal end and the distal end , the hand welding extruder further comprising: a material inlet channel for feeding plastic material; a material outlet at the distal end ; an extruder unit having a longitudinally extending extruder casing encompassing a processing chamber of the extruder unit , a central extruder axis extending along the central portion , a central extruder screw arranged coaxially with the extruder axis and configured to convey the plastic material from the material inlet channel through the processing chamber towards the material outlet , and at least one extruder heating element for heating the plastic material inside the processing chamber ; a handle for holding and guiding the hand welding extruder ; an air blower unit for blowing hot air towards a welding site in the vicinity of the material outlet , the air blower unit having a longitudinally extending air blower casing , an air inlet at an end of an inlet air duct , an air outlet arranged at a distal end of an outlet air duct in the vicinity of the material outlet , and a fan arranged to convey air from the inlet air duct to the outlet air duct of the air blower unit ; and a motor unit arranged between the extruder unit and the proximal end and configured to drive the extruder screw and the fan of the air blower unit ; characterized in that the air blower casing at least partially circumferentially encompasses at least a portion of the length of the extruder unit , the inlet air duct at least partially encompasses circumferentially at least a portion of the length of the extruder casing and/or the outlet air duct , and wherein the air inlet is arranged at the distal end of the inlet air duct and preferably is substantially directed to the distal end . a material inlet channel for feeding plastic material; a material outlet at the distal end ; an extruder unit having a longitudinally extending extruder casing encompassing a processing chamber of the extruder unit , a central extruder axis extending along the central portion , a central extruder screw arranged coaxially with the extruder axis and configured to convey the plastic material from the material inlet channel through the processing chamber towards the material outlet , and at least one extruder heating element for heating the plastic material inside the processing chamber ; a handle for holding and guiding the hand welding extruder ; an air blower unit for blowing hot air towards a welding site in the vicinity of the material outlet , the air blower unit having a longitudinally extending air blower casing , an air inlet at an end of an inlet air duct , an air outlet arranged at a distal end of an outlet air duct in the vicinity of the material outlet , and a fan arranged to convey air from the inlet air duct to the outlet air duct of the air blower unit ; and a motor unit arranged between the extruder unit and the proximal end and configured to drive the extruder screw and the fan of the air blower unit ; characterized in that the air blower casing at least partially circumferentially encompasses at least a portion of the length of the extruder unit , the inlet air duct at least partially encompasses circumferentially at least a portion of the length of the extruder casing and/or the outlet air duct , and wherein the air inlet is arranged at the distal end of the inlet air duct and preferably is substantially directed to the distal end . <EOS>