aids in the removal of the boneless flesh being accumulated inside the drum. An oscillating pre-press (7), reduces the fish thickness in such a way that it can be introduced between the drum and the matching beams (2) for the final pressing. A camshaft (8) moves the matching beams. An eccentric mechanism (9) is used to set the gap between the drum and the matching beams. All movements are provided by the gear chain (10). A mechanical seal (11) hold scales and raw material in place. Skins, scales and bones exit through the hopper (12), and deboned fish flesh exits through a hopper (13).