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.