A device is provided for depositing a treatment substance on the surface of a moving thread. The device comprises a tank configured to contain a liquid solution of the substance that is used to deposit the substance on the surface of the thread. The device also includes at least one nozzle having a nozzle inlet configured to receive said solution. The at least one nozzle is directed to spray the received solution towards the thread with a spray velocity in a form of jets, and the jets converge on the thread to adjust a thickness of the solution remaining on the thread by removing excess liquid entrained by the thread. The device further includes a pump that is coupled to the nozzle inlet and a treatment apparatus. The pump is configured to regulate the spray velocity according to a run speed of the thread.