How to make a cast for metal?
Metal casting is pretty old. Over 7,000 years old, to be more precise. During the casting process, molten metal is poured into a mold. The metal and mold are then cooled, the metal object is removed, and the finishing process can be started. This process is pretty universal and can be seen in action at a foundry or even a jewelry manufacturer.
But how do you make a cast for pouring metal? Does the cast need to be incredibly durable and impervious to the tremendous amount of heat from the molten metal? We’ll discuss all that and more, right here. Let’s begin.
What kinds of things are made with metal casting?
Since its inception over 7,000 years ago, metal casting has been used to create a variety of different items, like tools, weapons, artifacts, and jewelry.
It’s an incredibly versatile process that involves pouring liquid metal into a cast or mold. Rather than shaping metal with a cutter and a welder and risk having seams and cracks in the finished product, casting is a solid chunk where the finished product is pretty much how the item is going to look, no extra welding or cutting required.
So as you can imagine, the initial mold creation is very important. It’s imperative to be certain the mold is exact before you start pouring liquid metal into it, otherwise the finished product won’t be what you’re looking for.
Is all casting the same?
You’d think that having melted metal poured into a mold, the mold would have to be incredibly strong to stand up to the immense heat created from the liquid metal.
But the most common casting is made using sand. Sand is incredibly cost effective and, believe it or not, can take incredibly high temperatures.
This makes it ideal for casting metal. The one thing to remember, however, is that at the end of the casting process, the mold is destroyed in order to get the metal object out.
There are, of course, other types of casting, including shell molding (a form of sand casting that uses a resin and sand mixture), die casting, lost-wax casting, permanent molds, and semi-permanent molds.
Your desired outcome and the finish you’d like your object to have will determine which casting method is best for you.