Diecast models

The term die-cast toy here refers to any toy or collectible model produced by using the die casting method of putting molten lead or zinc alloy in a mold to produce a particular shape. Such toys are made of metal, with plastic, rubber, glass, or other machined metal parts. Wholly plastic toys are made by a similar process of injection moulding, but the two methods are distinct because of the properties of the materials.

The metal used in die-casting is either a lead alloy (used early on), or more commonly, Zamak (called Mazak in the UK), an alloy of zinc with small quantities of aluminium and copper. Lead or iron are impurities that must be carefully avoided in Zamac, as they give rise to a deterioration of the metal most commonly called zinc pest. The terms white metal or pot metal are also used when applied to alloys based more on lead or iron. The most common die-cast vehicles are scale models of automobiles, aircraft, military vehicles, construction equipment, and trains, although almost anything can be produced by this method, like Monopoly game pieces, furniture handles, or metal garden sprinklers.

Diecast (or die cast, or die-cast) toys were first produced early in the 20th century by manufacturers such as Meccano (Dinky Toys) in the United Kingdom, Dowst Brothers (TootsieToys) in the United States and Fonderie de précision de Nanterre (Solido) in France. The first models on the market were basic, consisting of a small vehicle body with no interior. In the early days, as mentioned, it was common for impurities in the alloy to result in zinc pest, and the casting would distort, crack, or crumble. As a result, diecast toys made before World War II are difficult to find in good condition. The later high-purity Zamak alloy avoided this problem.

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