How flying discs are made

A flying disc has a wing's cross-section, and most are molded in one shot from melted plastic pellets.

stations: 7
things upstream: 40
raw sources: 15
steps from the ground: 8

The short version

A flying disc is injection-molded. Plastic pellets are melted in a heated barrel and pushed by a screw into a closed metal mold shaped like the disc, then cooled until hard and released. Ultimate and classic discs are usually polyethylene, and disc golf discs are mostly polypropylene blends. A blade trims the rim and a hot stamp adds the logo.

Cut the metal mold

A two-part mold of aluminum or steel is made for each design, with the inverse shape of the disc. Its cavity sets the airfoil: a rounded dome that lifts like a wing, and a rim.
Load the plastic pellets

Millions of tiny pellets drop from a hopper, along with colored pellets. Classic and ultimate discs use polyethylene. Disc golf discs start from polypropylene, blended with a smaller share of other plastics to make them stiffer or gummier.

Goes in
Polyethylene Polypropylene
Melt in the barrel

The pellets travel down a heated barrel and become a thick liquid.

300 to 450 °F
Shoot it into the mold

The mold is clamped shut under pressure. A screw or ram forces the molten plastic into the cavity, and more pressure holds it there until every curve fills.
Chill and eject

Water or air channels in the mold cool the plastic until it holds its shape. The mold opens, and rods, a plate or a blast of air push the disc out.
Trim the rim

A sharp blade runs around the rim to take off the flash, the thin excess left at the mold's seam. Makers differ here, and some discs keep a visibly uneven edge.
Hot-stamp the logo

Discs are checked for weight and size, then stamped. Heat from above transfers an adhesive design onto the flight plate, the flat area inside the rim.

Goes in
Ink

End of the lineFlying disc

Worth repeating

The word Frisbee came from the Frisbie Pie Company, whose empty pie tins Yale students had tossed around.
Disc makers guard their plastic recipes closely, and small changes turn the same base from gummy to stiff.
Before the Pluto Platter, early flying discs were made of flexible polypropylene by a molder in Southern California.