How golf balls are made

Golf balls are dimpled because players noticed that scuffed, nicked balls flew better than smooth ones.

stations: 8
things upstream: 65
raw sources: 21
steps from the ground: 10

The short version

A modern golf ball has a molded rubber core, often with one or more layers around it, and a thin plastic cover. The core is pressed and heated in a mold, then covered with a tough urethane or ionomer shell. The cover mold carries a pattern of dimples. The ball is trimmed, painted and printed.

Mix the core rubber

Synthetic rubber is blended with additives into a dough, which is cut into slugs sized for one core each.

Goes in
Synthetic rubber
Press and heat the cores

Slugs are squeezed in a mold under heat, curing into a hard, bouncy sphere. Balls with more layers are two-piece, three-piece or four-piece.
Add a middle layer

Premium balls get a mantle between core and cover, which is molded around the core in a second step. A two-piece ball skips this.

Goes in
Polyurethane
Mold the dimpled cover

The core is placed in a mold with a pattern of dimples, and a plastic cover flows around it. Common cover plastics are ionomers and urethane.

Goes in
Polyurethane
Trim and buff

The seam where the mold halves met is ground off, and the surface is smoothed.
Paint and clear-coat

Balls are primed, painted white or another color, and covered with a clear coat. Dimples must stay sharp.

Goes in
Paint
Print the logo

Brand names and numbers are pad-printed on and sealed.

Goes in
Ink
Weigh and check

Balls are checked for size and mass. Under the rules, a ball can weigh no more than 45.93 g and be no smaller than 42.67 mm across.

End of the lineGolf ball

Worth repeating

Early golf balls were leather pouches stuffed with boiled feathers, and an experienced maker could finish only a few in a day.
The first liquid-filled balls had caustic cores, which injured children who cut them open, and makers dropped them by the 1920s.