Abstract: A method for holding a workpiece to be machined including the steps of: includes manufacturing a locking jig for locking the workpiece on a support base by additive production techniques wherein the locking jig includes a wall defining a loop. Irregularities present on at least one end of the wall arrangement are eliminated to define a support surface for the workpiece to be machined. A seat is formed in at least one end of the wall for housing a seal. At least one opening is formed on the support base and connected to at least one inner space of the loop on one side and with a suction device on the other side. A vacuum is supplied through the opening and the inner space which enables the workpiece to stick to and remain stationary with respect to the support surface during machining of the workpiece.

Abstract: A method is disclosed for producing a mould that is suitable for moulding a tool that is suitable for providing support and shape to a preform made of composite material, in which the mould defines a forming die provided with a forming surface with double curving, the method providing the forming of a monolithic solid by an additive manufacturing technique in a construction direction, the monolithic solid comprising a sandwich structure of curved shape that extends between two end edges extending in length in the construction direction, the sandwich structure comprising an inner core that has a section with a corrugated profile.

Abstract: A method is disclosed for holding a workpiece (P) to be machined comprising the steps of: manufacturing a locking jig (1) for locking the workpiece (P) on a support base (2) by additive production techniques, the locking jig (1) comprising wall arrangement (3) defining a loop (4a); eliminating the irregularities present on at least one end of the wall arrangement (3) so as to define a support surface for the workpiece (P) to be machined; making a seat (6) in said at least one end of said wall arrangement (3) intended for housing a seal (7); making at least one opening (8) on the support base (2) connected to at least one inner space of said loop (4a) on one side, and with a suction device on the other side; and applying a depression that, through the opening (8) and the aforesaid inner space, enables the workpiece (P) to stick to and remain stationary with respect to said support surface during machining of the workpiece (P).