Magnets Cooked Ham Silver Teapots Crash Test Dummies
Today on "how it's made"... Magnets... Cooked ham. Silver-plated teapots. And crash-test dummies. You can't see or feel the force causing this globe to levitate, but it's not magic, it's magnetic. An essential part of our daily lives, magnets are used for a lot more than just sticking stuff to the fridge. They help run motors and generators and are also found in computers, televisions, and microphones. Magnets occur in nature. But only two centuries ago, scientists figured out how to make them using metal and electricity. Production at the magnet foundry begins with a creation of a mold. A tray containing four magnet shapes is loaded into a machine that fills it with sand. A worker removes the pattern and smoothes the surface dimpled by the machine's lid. Then it's back inside. This time the machine pumps in gases that chemically alter the sand, hardening it in a matter of seconds. The sand slab is now a durable mold. And these molds are made in a wide variety of shapes and sizes. Now it's time to mix together the ingredients for the magnets themselves. They include copper, cobalt, sulfur, nickel, pure iron, aluminum, and titanium. All of these metals are loaded into an electrical induction furnace. It generates a pulsating electromagnetic field that heats the metal to almost 3,000 degrees fahrenheit, melting everything into a molten soup. The metal is poured into the molds. Because the gases that harden the sand are highly flammable, the molds burst into flames. Still ablaze, they slide to another part of the foundry where workers knock them to the floor and bust them open with sledgehammers. This lets the air in, cooling the molds and allowing the gases to burn off. All of the pieces are shoveled into a bin, and workers separate the metal from the sand chunks using what else? A magnet. But these metal pieces aren't yet magnetized themselves. That will come later. A set of rings designed for use in electric motors is threaded onto a copper pipe. The ring-covered pipe is placed in a tube. Then, silica sand is packed in to hold the rings in position. Both ends of the tube are sealed with concrete. Then, it's into an electrical furnace. It heats the tube until it's red-hot. This superheating primes the rings inside to accept an electromagnetic field which will be delivered by this metal rod. The rod slides down the center of the copper pipe and is clamped into place. Water keeps the pipe from melting as a low-voltage, high-current charge is delivered to the rings inside. Workers break open the seal. The process has left the rings mildly magnetized. Any rough edges are smoothed away. At this point, the magnets are pretty useless. But this machine empowers them with a strong electromagnetic charge. The establishment of that weak magnetic field earlier ensures that the magnetization is now properly oriented. Now, that's some serious magnetic muscle. The wide array of magnets manufactured today are critical to our daily lives because their invisible power helps keep so many things running. Up next-- turning raw pork into a succulent smoked ham. Ham comes from the hind leg of a pig. You can buy it raw and cook it yourself, or you can buy it already cured and smoked. You can buy your ham boneless or with the bone still intact. Bone-in ham has more natural flavor. The process starts with raw hams fresh from the slaughterhouse. The factory's automated sorting system weighs each one, then knocks it into the appropriate vat. By grouping hams of similar size together, the factory can better control the quality of the curing and cooking processes. Each vat empties into a tumbler which spins the hams for about five minutes. This loosens the skins so that workers can quickly remove them. They use an automatic trimming machine to skin the back portion, called the butt. In keeping with traditional style, the machine leaves just a small amount of skin on the thin part of the leg, called the shank. Now the circular wizard knife does its magic, removing all but a thin layer of fat. Finally, the base of the shank, called the hock, is chopped off. Now a curing solution is prepared, made of water, sugar, salt, and a few secret ingredients. This mixture gives the ham its trademark flavor and pink color. Without it, the meat would end up looking and tasting like a pork roast. Pipes feed the curing solution to an injection machine armed with 138 needles. As the hams pass below, they're thoroughly and evenly injected with solution. And all that piercing tenderizes the meat. Next, workers load a machine called the stuffing horn, which fires each ham into a heat-resistant cotton net. Workers seal each one with an aluminum clip, then cut off the excess netting. Cooking hams on trays would flatten the underside. But hanging them by nets keeps them nice and round. The cooking racks are transferred to a food-processing oven, the industrial equivalent of a traditional smokehouse. Hickory wood chips go into the oven smoker. Then a worker starts her up. For the next 12 hours, the hams slow cook at temperatures ranging between 150 and 180 degrees fahrenheit. This tenderizes the meat and gives the smoke ample time to seep in. After cooking, the hams get a cold ten-minute shower. This rinses away the drippings that fall from the higher hams onto the lower ones. Then it's on to the chill area, where over the next 36 hours, the hams cool to around 30 degrees fahrenheit. Next, the nets come off and packaging begins. The factory sells hams whole, or, using a band saw, slices them into halves or smaller sizes such as single-portion ham steaks. Workers bag the ham in plastic, then position a soft, plastic pad over the bone to prevent any sharp edges from ripping through the airtight seal. Each bag is positioned for sealing. Then, an automated vacuum chamber descends over each bag, sucking out the air and sealing the plastic. A robotic arm transfers the hams to a conveyor belt leading to a hot-water bath. Just five seconds in hot water is enough to shrink the plastic tightly around the ham. This airtight seal will keep the ham fresh in your refrigerator for three months, and up to nine months in your freezer. Coming up-- the artistry behind some of the world's finest teapots. The mayans started using pots like these 2,600 years ago, probably for hot chocolate. They've evolved since then. And today, aficionados consider them essential for that perfect cup of tea. Silver-plated teapots come in many different styles, and making them requires the talent and skill of an old-world master. A century-old hand-circling machine cuts a perfect circle out of a brass sheet that's 6/100 of an inch thick. Then the disk heads to the press. After lubricating the press surface with vegetable oil, the disk is positioned and covered with a polyurethane stopper. As the press applies its three tons of pressure, the die moves upward, shaping the disk from underneath. The stopper, meanwhile, provides a counterpressure to keep the die from breaking the brass as it thins and stretches. They call this the draft shape. It then goes into another die that produces the final shape of the teapot's base. Next, they solder on the teapot rim, which was made the same way. A craftsman then hammers the metal to remove any imperfections left by the pressings and punches in the maker's mark. Spinning is another technique used to form metal teapot parts. Here, a craftsman shapes a copper teapot mounted on a lathe. The metal is decorated using a technique called hand chasing. With a paper stencil, he applies the design in white powder. He pencil traces the pattern, then hammers in the design with a variety of tools. This intricate process requires the talented hands of an expert artisan. For the teapot spout, workers press brass plates into left- and right-side dies. A quarter-ton press produces the final spout shape. Soldering paste is brushed onto the halves. They're wired together, then fired to 600 degrees fahrenheit. The spout gets an acid bath to remove all of the impurities left behind from the soldering process. Workers polish the teapot with three progressively finer grades of pumice, which is crushed volcanic rock. One final buffing ensures the surface is perfectly smooth. With diamond-tipped hand tools, engravers can etch anything onto the teapot from custom designs to company logos. Workers now screw on the lid, wire up the teapot, and immerse it in cleaning chemicals followed by a silver-plating bath. Just before shipping, they attach hardware and perform a final cleaning. Finally, the teapots are wrapped in acid-free cellulose to prevent the silver from tarnishing. It takes a highly skilled team of craftspeople to create these unique teapot designs in styles ranging from elizabethan to ultra modern, beautiful and functional. When we return-- bringing crash-test dummies to life. Crash-test dummies may look human, but they're actually high-tech guinea pigs for a wide range of impact tests. So, how do they make dummies whose form and structure mimic the human body? You're about to find out. Crash-test dummies are designed to take some serious hits. Automakers use the data they provide to build safer cars, vans, and trucks. A dummy's anatomy is pretty simple. Beneath its vinyl skin, there's a metal skeleton made of steel and aluminum bones. Those bones contain load cells, electronic devices that measure crash force. Production of the load cells begins with a machine that shapes steel bars using a solid carbide end mill. Lubricant cools the intense heat and washes away the metal particles. Using a precision tool called the dial indicator, workers verify the load cell's dimensions to within 2/1,000 of an inch. Next comes the strain gauge-- the component within the load cell that measured crash force. The hair-width wires that connect the strain gauges are so delicate that soldering them requires a microscope. The vertebra in the dummy's neck also contains a load cell. The strain gage soldered inside it measures not just lateral and vertical forces, but also twist, or torsional force. The completed bones and corresponding load cells are laid out, but they can't be connected until the dummy's rib cage is complete. To make the rib cage, steel bands are bonded to a flexible damping material. This material was originally designed to deaden sound in nuclear submarines. It allows the dummy's rib cage to compress just like the real thing. A technician bolts the entire rib assembly to the spinal column and covers it with a plastic chest plate called a bib. The long bones and load-cell forms are inserted into aluminum molds. Workers then bolt the molds shut and pour in liquid vinyl. The molds bake at around 350 degrees fahrenheit for 10 to 20 minutes. When they come out, workers cut away any flash-- the excess vinyl that oozes out during the baking process. Then, a technician inspects the components to ensure an accurate fit. This is no ordinary vinyl. It's specially designed to resemble human flesh in consistency and density. This gives researchers realistic crash data. Now, it's time to install the bones into their respective vinyl compartments, starting with this tibia or shin bone. Zippers allow the engineers to easily remove the components after performing a crash test. A technician bolts all the dummy's joints in place and ensures they have a human-like range of motion. Using a neck-compression tool, a technician lines up a load sensor with the neck vertebrae and fashions the completed neck assembly to the dummy's head. Next, the upper body is completed. The thorax is bolted onto the pelvis, the head and neck assembly onto the thorax. Then, the vinyl jacket is fitted over the chest. Finally, the technician bolts on the limbs. Crash-test dummies range in size from newborns all the way up to 225-pound adults so that auto manufacturers can be sure their seat belts and air bags protect everyone equally well. It took a full 12 weeks to make this dummy, and now he's ready for a life of hard knocks to make traveling safer for all of us.