Abstract: A reinforcing element for cementitious or plastic material is disclosed which comprises a bundle of a plurality of strands of reinforcing material, the strands in the bundle being generally coextensive and being interconnected in a limited area intermediate their ends to provide brushes of substantially unentangled strands on each side of the intermediate area. There is also disclosed a method of making such elements which includes the steps of preparing a length of yarn comprising a plurality of reinforcing strands interconnected at substantially regular, spaced apart areas, the strands intermediate said interconnected areas being substantially unentangled. The yarn is then cut to produce elements having an interconnected area flanked by lengths of substantially unconnected fibers.

Abstract: A method and apparatus for interentangling ends of multi-filament yarn and tow which involves subjecting the overlapped ends to jets of gaseous fluid to interentangle the ends. The method involves employing a plurality of jets, one of which tends to rotate at least one of the filaments, and the other of which tends to move the filaments transversely. The jets act on the filaments when they are in motion from a previous jet. The apparatus provides a chamber for containing the overlapped ends and for defining the jets.