Method & means of forming threaded ties and rods

A method for manufacturing a helically-shaped member, the method including:

• providing profiled feed-wire comprising metal, the feed-wire having a central core and a plurality of longitudinal flanges extending outwards from the core and running parallel to the core;
• providing a die body made of plastic, the die body having an axial cavity formed through the die body and a plurality of internal helical grooves formed in the die body, each helical groove extending substantially the whole length of the axial cavity at a substantially uniform helix angle;
• engaging at least some of the flanges within respective internal helical grooves, and forcing the profiled feed-wire in an axial direction through the die body, whereby a plastic surface within at least one of the helical grooves deflects its respective flange thereby forcing the profiled feed-wire to helically deform as it advances through the die body;
• and
• extruding a helically-shaped wire from the die body.