Abstract: A method of forming a duct section from a web of material includes the steps of forming a series of perforations in a web of material, the series of perforations defining an outline of one of a hole or notch in a finished duct section, forming a male lock bend and a female lock seam in first opposed edges of the web of material, forming flanges in second opposed edges of the web of material, removing the portion of material interior to the series of perforations to form the hole or notch, and bending the web of material to form the finished duct section.

Abstract: A method of forming a duct section from a web of material includes the steps of forming a series of perforations in a web of material, the series of perforations defining an outline of one of a hole or notch in a finished duct section, forming a male lock bend and a female lock seam in first opposed edges of the web of material, forming flanges in second opposed edges of the web of material, removing the portion of material interior to the series of perforations to form the hole or notch, and bending the web of material to form the finished duct section.

Abstract: A method of forming a duct section from a web of material includes the steps of forming a series of perforations in a web of material, the series of perforations defining an outline of one of a hole or notch in a finished duct section, forming a male lock bend and a female lock seam in first opposed edges of the web of material, forming flanges in second opposed edges of the web of material, removing the portion of material interior to the series of perforations to form the hole or notch, and bending the web of material to form the finished duct section.

Abstract: A method of forming a duct section from a web of material includes the steps of forming a series of perforations in a web of material, the series of perforations defining an outline of one of a hole or notch in a finished duct section, forming a male lock bend and a female lock seam in first opposed edges of the web of material, forming flanges in second opposed edges of the web of material, removing the portion of material interior to the series of perforations to form the hole or notch, and bending the web of material to form the finished duct section.

Abstract: A jump rope comprising cable and handle assemblies. The handle assembly comprises grip and bearing sections, the bearing section threadably connected to the grip section and comprising a housing and a heim joint, the heim joint comprising a metal ball that swivels within the heim joint housing. The grip section comprises female threads tor receiving a male threaded end of the bearing section. The cable assembly comprises a cable and cable stop. The cable is attached to the heim joint by slidably inserting a cable end through the aperture in the ball. A distal end of the heim joint comprises internal female threads that engage with a male threaded proximal end of a rotatable shaft located within the bearing housing. The rotatable shaft is supported by first and second ball bearings located on either end of the shaft so that the rotatable shaft may rotate freely within the bearing housing.

Abstract: A duct making apparatus bends a metal web to form a duct blank having a lock tab at a forward end and having a Z-fold at a rearward end. Prior to shearing off the duct blank from the metal web, the apparatus bends the duct blank to insert the lock tab into the Z-fold, and further bends the Z-fold to form a clinch tab holding the lock tab into the Z-fold. After shearing off the duct blank from the metal web, the apparatus clinches the clinch tab over the lock tab to form a completed duct blank.

Abstract: A duct making apparatus bends a metal web to form a duct blank having a lock tab at a forward end and having a Z-fold at a rearward end. Prior to shearing off the duct blank from the metal web, the apparatus bends the duct blank to insert the lock tab into the Z-fold, and further bends the Z-fold to form a clinch tab holding the lock tab into the Z-fold. After shearing off the duct blank from the metal web, the apparatus clinches the clinch tab over the lock tab to form a completed duct blank.