Abstract: The present invention provides a method of forming a filter rod (R) of separated fibres and/or randomly oriented filter material fibres (F) for the tobacco processing industry, the method comprising: supplying separated filter material fibres (F) to an inlet (I) of a conveyor device (2), conveying the separated filter material fibres (F) along a process path (P) in a conveying direction (D) from the inlet (I) to an outlet (O) of the conveyor device (2), whereby a strand (4) of the filter material fibres (F) is formed along the process path (P), introducing at least one additive (A), especially a binder, to the strand (4) of filter material fibres (F) on the process path (P) in the conveyor device (2) at a position that is closer to the outlet (O) than the inlet (I), and consolidating the filter material fibres (F) into a filter rod (R) by wrapping the strand (4) of filter material fibres (F) with a wrapper material (6) after the strand (4) exits the outlet (O) of the conveyor device (2) in the conveying direc