Abstract: A twist tube for false-twist devices for texturing textile yarns is described wherein the thread guide pin has terminal portions coated with a solderable metal, such as nickel. The terminal portions are mounted in bores on each side of the elongated metal tubular part of the twist tube and at least one of the coated terminal portions is soldered into its associated bore at a temperature which does not modify the crystalline metal structure of the twist tube nor cause thermal deformation of the twist tube. The opposite terminal portion may be similarly soldered into its bore or it may be elastically mounted in its bore. Processes involving soft soldering and hard soldering are described.