Abstract: A progressive die for producing collared holes in a sheet. The die includes a first station having a pattern of three punches producing three spaced apart holes in the sheet. A main punch at the second die station is extended into the three holes producing a single hole with portions of the sheet extending therein. The straightening punch mounted at the third station of the die has a diameter larger than the single main hole and is extended therethrough bending the portions extending into the hole outwardly forming a collar. The curling punch mounted at the fourth station of the die, curls the distal end of the collar outwardly.

Abstract: A progressive die for producing collared holes in a sheet. The die includes a first station having a pattern of three punches producing three spaced apart holes in the sheet. A main punch at the second die station is extended into the three holes producing a single hole with portions of the sheet extending therein. The straightening punch mounted at the third station of the die has a diameter larger than the single main hole and is extended therethrough bending the portions extending into the hole outwardly forming a collar. The curling punch mounted at the fourth station of the die, curls the distal end of the collar outwardly.

Abstract: A method for forming collared holes in a workpiece. The tool has a drill formed at one end thereof for forming a hole in the workpiece. Immediately adjacent and contiguous to the drill is a tapered configured portion which is extendable into the hole formed by the drill. Rotation of the tool causes a collar to form around the hole as the tapered portion of the tool is rotated and forced into the hole. The tool has a constant diametered rod configured portion to straighten and polish the inside surface of the collar formed around the hole in the workpiece. The method of forming the collared hole in a workpiece includes the steps of forming the hole in the workpiece, inserting the tapered tool into the hole so as to contact the tapered tool against the circumference of the hole. The tool is then rotated and the tapered portion is forced further through the hole so as to form the collar integral with the workpiece and surrounding the hole while protruding from opposite sides of the workpiece.

Abstract: A progressive fin die having means for preventing metal particle buildup around the punch with the means stripping the workpiece from the punch. A plurality of draw punches are arranged with decreasing diameters in a row. A ram is movable to and from the draw punches and includes a plurality of draw bushings. Movement of the ram toward the draw punches results in the punches forming bonnets in the workpiece positioned between the punches and bushings. Spring biased stripper rods extend through the bushings and are operable to force the workpiece from the bushings. A compound pierce and straightening station includes a hollow pierce bushing mounted to the frame for receiving a pierce punch movable to and from the frame by a ram. A straightening bushing encircles the pierce punch and is externally engageable with the bonnet formed by the draw punches. A stripper bushing is slidably mounted to the pierce punch and is disposed between the straightening bushing and the pierce punch.

Abstract: A progressive fin die having means for preventing metal particle buildup around the punch with the means stripping the workpiece from the punch. A plurality of draw punches are arranged with decreasing diameters in a row. A ram is movable to and from the draw punches and includes a plurality of draw bushings. Movement of the ram toward the draw punches results in the punches forming bonnets in the workpiece positioned between the punches and bushings. Spring biased stripper rods extend through the bushings and are operable to force the workpiece from the bushings. A compound pierce and straightening station includes a hollow pierce bushing mounted to the frame for receiving a pierce punch movable to and from the frame by a ram. A straightening bushing encircles the pierce punch and is externally engageable with the bonnet formed by the draw punches. A stripper bushing is slidably mounted to the pierce punch and is disposed between the straightening bushing and the pierce punch.