There are disclosed one-piece chuck structures for use in winding machines and particularly, but not exclusively, for use in high speed winding machines for the take-up of synthetic plastics filament. These one-piece chuck structures comprise a first elongated tubular portion adapted to receive one or more bobbin tubes and a second elongated tubular portion integral with the first elongated tubular portion and of reduced external diameter relative thereto. Bearings cooperate with the exterior of the second elongated tubular portion such that the first elongated tubular portion and the second elongated tubular portion are rotatable about a common longitudinal axis. Also disclosed are hollow bobbin tube-engaging elements as well as double-arm tube-positioning members which can be used with such and other chuck structures.
