Molding

Greensand molds with gating system.

The black casting is iron and the others are aluminum.
Gating iron (Latin: ferrous) is different than gating aluminum or bronze (non-ferrous). Dross is produced with non-ferrous alloys , but NOT with iron. Dross is similar to the foam on top of beer.
When gating non-ferrous castings, dross is carried beyond the gate by the deep runner, clean metal enters the casting.
When gating iron, the metal is so heavy, 2 large openings (sprue/riser) are used to equalize the pressure.

Parameters of Gating
Alum castings 3lbs. or less- Bronze castings 9lbs or less
1/2″ sprue, 1″x 1″ runner up to 10″ long.

Alum castings 3-8 lbs.- Bronze 9-24 lbs.
3/4″ sprue, 1.5″x 1.5″ runner up to 14″ long.

Alum castings over 8 lbs. Bronze over 24 lbs.
1″ sprue, 2″x 2″ runner up to 18″ long.

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Apprentice Test

Cup, spoon and saucer casting

This casting is a symbol of achievement and excellence in the foundry industry. This test of molding skill originated many years ago in the British Isles. Foundrymen there considered molding an art. An apprentice had to spend many years learning and practicing the trade  before becoming a Journeyman.

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