A core for winding yarn can include an oblong hollow body and a laser-cut structure disposed through a portion of a wall of the hollow body adjacent to an end of the hollow body. A method of cutting a core for winding yarn can include providing a core comprising an oblong hollow body, and irradiating a wall of the hollow body with a laser beam to form a laser-cut structure. A method of winding yarn can include placing a core on a winding mandrel, placing a tail of a length of yarn through a laser-cut structure of the core, and spinning the core to wind the length of yarn around the core. A bobbin can include yarn wound around a core including a laser-cut structure.

The invention relates to a device (6) for inserting an optical fiber (100) through a port (110) in a rim (11) of a bobbin, characterized in that along the direction in which the optical fiber runs, the device comprises: a system (60, 61) for moving the optical fiber along, a tool (63) for cutting the optical fiber, a first optical fiber-guiding element (65) comprising a slot, the base (650) of which defines a curve between an inlet (651) facing the moving system (60, 61) and an outlet (652) that is to face the port (110) in the rim of the bobbin.

The invention relates to a device (6) for inserting an optical fibre (100) through a port (110) in a rim (11) of a bobbin, characterised in that along the direction in which the optical fibre runs, the device comprises: a system (60, 61) for moving the optical fibre along, a tool (63) for cutting the optical fibre, a first optical fibre-guiding element (65) comprising a slot, the base (650) of which defines a curve between an inlet (651) facing the moving system (60, 61) and an outlet (652) that is to face the port (110) in the rim of the bobbin.

The invention relates to a device (2) for winding an excess length (100) of an optical fibre onto a bobbin (1) comprising: a cylindrical reel (10), two rims (11, 12) extending radially from each end of the reel (10), one (11) of said rims being provided with a port (110) for the optical fibre, a magazine (13) which has a cylindrical surface for receiving a winding of the excess length (100) of the optical fibre, is separated from the reel (10) by the rim (11) provided with the port (110) and has a circumferential edge (130) for retaining the excess length of the optical fibre,

the device is characterised in that the same comprises: means (22) for storing the excess length of the optical fibre, and means (21) for winding the excess length of the optical fibre about the magazine (13),

the means (21, 22) being able to cooperate in such a way as to unwind a certain length of the optical fibre stored on the storing means (22) and wind the excess length about the magazine (13).

An arrangement of an elongated element wound on a spool is presented. The elongated element has a leading end having a bent part and an unbent part. The bent part further having a beginning part and a trailing end. The leading end is positioned on the core of the spool and the bent part deviates at least for a part from a winding direction. The elongated element further forms subsequent windings in the winding direction on the core. At least one of the subsequent windings is wound over the beginning part of the bent part while an adhesive is provided to fix the trailing end of the bent part on the core simultaneously thereby securing elongated element on the spool.