![]() Even if an old piece is taken apart and used as a pattern, normal shrinkage will mean the reproduction will be smaller than the original. Cast iron shrinks 3/32 to 1/8 of an inch per foot between mold and casting this means each time a piece is copied, a certain amount of distortion occurs which results in loss of detail. ![]() Most cast iron reproductions on the other hand, use actual antique toys as master patterns or copies of other copies. 8) and is seldom found on old pieces but is common among reproductions.Īnother reason old cast iron toys generally have sharper details is that they were cast from a mold made from an original master pattern. Most new molds don't fit together very well and molten metal runs out through gaps where mold halves meet. The finer sand also meant the two halves of the mold fit together tightly. Old castings, therefore, almost always have sharper lines and more detail new castings are generally less sharp, blurred and lack the fine details found in old pieces cast with finer sand. The finer the sand, the tighter it could be packed around the master pattern which transferred more and smaller details to the sand mold. Better yet, depending on the type of toy, ask the seller to take it apart for a thorough examination.Ī second major difference caused by the casting sand is the amount of detail in new and old cast iron. The rough texture is the most obvious on unpainted surfaces so try to look on the inside or underside of toys. New cast iron generally has small prickly bumps that rise above the surface and holes or pits that go below the surface (Figs. The surface of old cast iron both looks smooth and feels smooth to the touch. This means that old cast iron almost always has a much smoother surface than new castings made with coarser sand. Casting sand used in original molds was generally finer than the casting sand used in modern reproductions. Several important differences between new and old cast iron toys are related to the casting sand. However, there are certain differences that let you tell new from old. New cast iron toys are made in the same general way as old originals. Gates and runners are important because the marks they leave can often be used to tell how and when the casting was made. ![]() A pattern which can make more than one piece at each pouring, like the master pattern in Fig. The point where the runner branches off into the casting is called a gate (Fig. 4, A) is a channel usually down the center of a mold which feeds molten metal into the individual castings. Two other basic sand casting terms you should know are runner and gate. The number of times a mold can be used depends on the skill of the workers, the complexity of the master pattern and the level of quality acceptable in the finished casting. Sand molds are generally used only once but may be used again. After cooling, the frames are separated and the cast piece is removed for finishing. The iron runs into the hollow impression and forms a copy of the master pattern. The frame halves are locked together and the molten iron is poured into the mold. Each mold requires two frames- one frame for the top half of the mold, a second frame for the bottom (for more details on casting see the glossary of foundry terms at the end of this article). When the pattern is removed, a hollow impression of the pattern is left in the sand (see Figs. The pattern is placed in the frame and tightly packed with a special sand called casting sand or foundry sand. Master patterns are placed in a wooden four sided box called a casting frame. Most toy master patterns were designed to make several parts at each casting. Master patterns can be wood, plaster and other materials but most toys used brass or bronze masters for better detail and long life. Sand casting begins with a full sized three dimensional model or master pattern. The process is called sand casting because the molten iron is poured into molds made from tightly packed sand. This article will discuss the ways to tell new from old cast iron toys beginning with an explanation of iron casting.Īll cast iron toys, both new and originals were made with a foundry method called sand casting. Unfortunately, those are also the very reasons why so many toys are reproduced in cast iron. Cast iron was the 19th century equivalent of today's modern plastics - the raw ingredients were cheap, it could be made in almost any shape, and identical pieces could be mass produced in molds.
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