Metal spool having high torque transmitting capacity between spool components

A metal spool comprising:

• a cylindrical barrel;
• a pair of flanges, each flange disposed at an end of the cylindrical barrel and having a central opening;
• a pair of flange hubs, each flange hub disposed in the central opening of one of the flanges;
• a pair of formed metal curls securing the ends of the cylindrical barrel to the flanges and the flange hubs, the metal curls formed of curled metal edges of the cylindrical barrel, the flanges and the flange hubs at the respective ends of the spool;
• and
• at least one detent in at least one of the metal curls, having a depth sufficient to cause beveled contact between the curled metal edges of the cylindrical barrel, the flange and the flange hub in the metal curl, yet insufficient to puncture the metal surface on the outside of the metal curl wherein the at least one detent comprises a plurality of detents at spaced locations radially about each of the curls.

A metal spool comprising:

• a cylindrical barrel;
• a pair of flanges, each flange disposed at an end of the cylindrical barrel and having a central opening;
• a pair of flange hubs, each flange hub disposed in the central opening of one of the flanges;
• a pair of formed metal curls securing the ends of the cylindrical barrel to the flanges and the flange hubs, the metal curls formed of curled metal edges of the cylindrical barrel, the flanges and the flange hubs at the respective ends of the spool;
• and
• at least one detent in at least one of the metal curls, having a depth sufficient to cause beveled contact between the curled metal edges of the cylindrical barrel, the flange and the flange hub in the metal curl, yet insufficient to puncture the metal surface on the outside of the metal curl and further comprising flattening paste adhering to a metal surface in said at least one of the curls between at least two adjacent contacting metal surfaces in the curl.

A metal spool, comprising:

• a cylindrical barrel;
• a pair of flanges, each flange disposed at an end of the cylindrical barrel and having a central opening;
• a pair of flange hubs, each flange hub disposed in the central opening of one of the flanges;
• a pair of formed metal curls securing the ends of the cylindrical barrel to the flanges and the flange hubs, the metal curls formed of curled metal edges of the cylindrical barrel, the flanges and the flange hubs at the respective ends of the spool;
• and
• flattening paste adhering to a metal surface in at least one of the metal curls between at least two adjacent contacting metal surfaces in the metal curl to thereby increase the coefficient of friction therebetween.

A metal spool, comprising:

• a cylindrical barrel;
• a pair of flanges, each flange disposed at an end of the cylindrical barrel and having a central opening;
• a pair of flange hubs, each flange hub disposed in the central opening of one of the flanges;
• a pair of formed metal curls securing the ends of the cylindrical barrel to the flanges and the flange hubs, the metal curls formed of curled metal edges of the cylindrical barrel, the flanges and the flange hubs at the respective ends of the spool;
• at least one detent in at least one of the metal curls, having a depth sufficient to cause beveled contact between the curled metal edges of the cylindrical barrel, the flange and the flange hub in the metal curl, yet insufficient to puncture the metal surface on the outside of the metal curl;
• and
• flattening paste adhering to a metal surface in said at least one of the metal curls between at least two adjacent contacting metal surfaces in the metal curl to thereby increase the coefficient of friction therebetween.