CNC Assembly Machines Lemon Tarts Miniature War Figures
Today on "how it's made"... Automated machines changed manufacturing forever when they began assembling parts. Cnc assembly machines have taken automation to the next level. Cnc is an acronym for computer numerical control. The machine is automated by a computer rather than by mechanics. To design a cnc assembly machine, engineers first analyze the sequence of tasks required to assemble the product. They then match each task to a pre-designed processing engine. The processing engines are linked together in a custom assembly sequence. Each engine is programmed to control its computer-guided motors, which perform the precise motions required to execute a task. The cnc machine's engines are mounted on a sturdy base frame. To construct it, workers cut steel tubes to the required lengths. They grind a joint in each piece... Then weld the pieces together by melting steel welding wire into the joints. They bolt a steel tabletop onto the base frame. It has cutouts for each engine. It's been ground perfectly flat. So the engines will be level with each other. Meanwhile, an electrical technician is assembling the machine's main control cabinet. It contains one industrial computer for each engine. A cnc machine has engines for performing rotary movements, linear movements, and for picking up and placing parts. The motors inside each engine have their own computers. They're programmed to perform movements at specific speeds and forces. Once the main control cabinet is assembled, workers bolt it to the base frame. Then they install steel bases for the engines. Some cnc machines require robotic arms. A computer-guided milling machine cuts rectangular bars of aluminum, shaping them into robotic arm components. This precision-measuring device ensures each milled part meets strict specifications. After the aluminum components receive an anti-corrosion coating, workers assemble them into a robotic arm. These self-lubricating sleeve bearings give the arm the ability to rotate. They add a second assembled arm to create a pair that works together to perform an assigned task. Each arm is controlled by its own motor, which follows the commands of the engine's computer. This coupling securely connects each robotic arm to the shaft of its motor. Each engine on the machine can have up to eight motors. The motors can operate independently or in unison. This engine has robotic arms that can pick up, hold, and release parts. To test the completed machine, a high-speed video camera captures images at 1,000 frames per second. The quality control team slows down the video to analyze and fine-tune the accuracy and efficiency of every motion. Just a few simple taps on the operator's touch screen can adjust the arm to move a millisecond faster. Or a millimeter further. Cnc machines can assemble small products at high speed. They also provide something traditional assembly equipment can't-- flexibility. A single machine can be reprogrammed multiple times for assembling different products. When life gives you lemons, why bother making lemonade when you can indulge in a luscious lemon tart? Not too sour, not too sweet, a lemon tart is a delectable dessert that you can make yourself. Or even better, leave it to the baking pros and buy ready-made. This thaw-and-serve lemon tart has a shortbread shell and creamy lemon filling topped with buttercream. Each batch of dough produced in this industrial mixer yields 449 tart shells. The first step is to lightly blend margarine, sugar, and salt for 2 or 3 minutes. Next, add pasteurized eggs and mix for about 2 minutes at slow speed. Fast mixing makes the dough too tight, causing it to crack. They add white flour while continuing to mix slowly until the ingredients are well-blended. Once the dough is ready, workers put it through what is actually a hamburger forming machine. It extrudes 1/4-pound dough patties. Workers place them in the middle of a nonstick aluminum tart pan three at a time. They mount the pan on a press, covering it with plastic. A die strikes the pan, flattening and spreading the dough evenly. The pans go into the oven, where they rotate for 23 to 24 minutes at 350 degrees fahrenheit. The dough bakes into a shortbread tart shell. Lemon juice and lemon oil are the key ingredients in the creamy filling. First, workers melt margarine on a stove... Then mix in sugar, lemon powder... And food starch to thicken the mix. They blend for 2 minutes, then add eggs. After another 5 to 8 minutes of mixing, they pour in boiled lemon juice and lemon oil. Boiling these acidic ingredients prevents the fats from curdling. The filling is ready. So they move the bowl from the mixer over to the depositing line. A pump transfers the contents to a hopper feeding a depositor. The depositor is pre-set to squirt 22 ounces of lemon filling in each tart. The filled tarts go into the oven for 11 minutes. The lemon tarts come out of the oven, cool at room temperature for 2 to 3 hours, then go into a freezer overnight. The next day, workers remove the frozen tarts from the pans. They gently remove any specks of browning, then spray on a light layer of glaze made from apricots. This adds a hint of sweetness. The glaze also prevents the filling from cracking when it's thawed for serving. Next, they put the tart in an automated cake slicer. The turntable rotates as the tart is cut into 12 slices with papers in between each one. This is for restaurants who serve the dessert by the slice. Workers embellish each slice with a flower made of buttercream, a decadent mixture of butter, egg whites, and sugar. They complete each flower with a dot of lemon filling in the center. This lemon tart is finished. They wrap it in a cardboard cake band printed with the brand name. They seal the tart in plastic film, insert it into a retail box, and ship it frozen to a store or restaurant. To serve this tasty dessert, you simply defrost at room temperature for about a half hour. Toy soldiers aren't just for children. They're a hobby for grown-ups that dates back over a century. The science-fiction novelist h.g. wells published the first set of rules for toy solider war games in 1913. The game is on. It's time to rally the troops. These mini soldiers are made of either metal or plastic and hand-painted by the game players. No detail is overlooked in making these war figures true to the historical period of the game. Players move the figures around tabletop scenery like chessmen on a chess board. And like chess, this is a game of strategy. It's a way to engage in the tactical elements of war without the violence of a real battle. Making miniature war figurines starts with the construction of a model. With only one hand and his prosthesis, a modeler expertly bends tin copper wire into a framework for the model. Each soldier needs to be 1.1 inches in length. So he shapes and trims the wire accordingly. Once he completes the wire skeleton, he sticks the leg prongs into a cork. This enables him to get a firm grip on the skeleton as he builds up the figure with epoxy putty. He sculpts a base layer using a dental tool that's usually used for scraping plaque. After the base layer cures, he builds up the chest and calf areas. After more curing time, he sculpts the soldier's tunic. Using a tool with a fine point, he pits the surface to simulate medieval chain mail armor. With skillful artistry, the miniature soldier takes shape. He inserts a wire into a drilled shoulder socket and applies putty to create a muscular effect. He builds up the sleeve and pierces it all the way around to continue the chain mail effect. He carves the rounded rim of the hat. This small-scale soldier is in fighting form. He's used to make a mold for tin soldiers that will look just like him. Meanwhile, another member of the team sculpts epoxy putty models that are three times larger. These models are used to mass-produce plastic war figures. Going large first and then scaling down is the only way to transfer all the details. As he carves hair details into the head of this french cavalry figure, he's careful to not leave any protruding bits. Otherwise, plastic could snag on molds made from them, jeopardizing the production of the plastic versions. With curing time between layers, it takes about a week to sculpt this french cavalry model. They're ready to make molds from the smaller scale models now. The mold maker arranges the epoxy models on a silicone rubber disk. He presses each one into the rubber. The ends leave little dents. He removes the model and slices it into the rubber with a surgical scalpel, cutting holes where the figures have left the indentations. He removes the silicone cutouts, then carves a narrow channel to connect the two slots. He inserts the model into the niche. He repeats this process with the other soldiers on the disk, then places the disk in a preheated steel vessel. He puts a lid on the vessel and transfers it to a vulcanizing press. In the press, heated plates squeeze it using pressure. This softens the rubber inside, melting around the figures, picking up the contours. This transfers the disk into a mold. Coming up next, the miniatures emerge from the mold shell battle-ready. In the age of video games, tabletop war games still have plenty of fans. The challenge begins with the acquisition of small armies of miniatures. Players hand-paint the soldiers and build elaborate backdrops with scenery. Then the games begin. As production continues, the mold-maker carves channels into the silicone disk. He links the channels to the impressions of miniature soldiers and military machinery that have been created by the models. The channels allow molten metal to flow into the impressions in order to cast copies. In the storeroom, there are thousands of silicone molds, each depicting different characters and props. When the order comes in, an apprentice makes the selection. Next, an operator puts the mold in a casting machine. As the mold spins in the machine, he adds molten tin through an opening in the lid. The spinning throws the liquid tin into the mold crevices. After the casting solidifies and cools, he extracts the little tin soldiers. These tin war figures are on their way to the gaming front lines. Making plastic war figures starts with an epoxy resin for a pattern. They add a hardener and blend the batch to the consistency of pancake batter. They transfer it to a larger bucket and place it in a vacuum chamber, which pulls out the air. In the process, the epoxy swells. Once the epoxy mixture deflates, a team brushes it onto sculpted military models arranged in a steel box. After filling all the crevices, they dispense more epoxy. A chute ensures a gentle flow, preventing the buildup of more bubbles. They repeat this on the other side of the models to create a two-part pattern. Once the epoxy hardens, they mill the outside of the pattern to pre-determined measurements. An employee then opens it and discards the models. He inspects the impressions they've left. They use this pattern to make a smaller-scale mold from steel. Using an automated saw, they carve smaller pieces from a block of nickel chrome steel. An automated milling tool machines the smaller blocks so the two of them will fit together to create one mold set. A carriage shunts the block back and forth between an abrasive wheel to grind the surface to precise measurements. A mold-maker follows the impressions in the epoxy pattern with a stylus, which moves a needle-like cutter. The cutter etches a template into the steel block that's three times smaller than the one in the epoxy pattern. Using a wand that generates high-frequency vibrations, he polishes the etchings in the steel mold. It's a gentle polish that doesn't damage any of the etching in the mold block. They drill channels in the steel to allow plastic to flow to the impressions. They also insert water-cooling pipes. They're ready to mass-produce plastic war figures. The machine melts plastic and injects it under pressure into the mold set. The plastic hardens, and the machine ejects the little soldiers connected by runners. This particular production includes miniature rifles and other military paraphernalia. They pack the plastic soldiers, their horses, and their guns into boxes for retail along with instructions for painting. After painting, the plastic soldiers and their tin comrades are in tip-top military form and ready for battle. There will be casualties. But of course, it's all just for fun. These miniature war figures are survivors. They will live on to fight many more battles.