Cast Iron Stoves Ultralight Aircraft Snow Groomers Rubber Bands
Cast-iron stoves have been adding warmth to people's lives for more than three centuries. Today there are new reasons to cozy up to this invention. It's had a major update. Modern stoves burn wood more cleanly and efficiently, providing heat without the dirty fallout from the chimney. Modern cast-iron stoves hardly resemble their smoke-belching, soot-spewing predecessors. The design creates a hotter fire, so it requires less fuel and releases little smoke. It all starts with a pile of iron scrap, things like old stoves, sinks, brake drums, and rotors. A magnetized crane transfers the scrap to a propane-fired preheater. 12 minutes spent in the preheater removes moisture from the iron scrap. The scrap iron spills into a hopper that funnels it into an electric furnace. The temperature in the furnace is a blistering 2,700 degrees fahrenheit, and the iron melts into a fiery liquid. The furnace tilts to pour the molten iron into a ladle for transfer. Next, they make the molds of the stove parts, using a mix of sand, clay, water, and coal. They blow the ingredients between the aluminum patterns. A hydraulic system squeezes the patterns together. The sand mix compacts and takes the shape of the patterns. They now have sand molds. The molten iron arrives and flows into a channel leading to the molds. As the liquid metal cools, it solidifies into the shape of the mold. A vibrating conveyor shakes and breaks the sand molds to reveal the cast-iron stove parts. A worker knocks off unwanted bits, and then it's into a blast cleaner. Inside the blast cleaner, steel grit bombards the stove parts to remove remnants of the sand molds and expose the metal. Essentially it blasts the dirt off, and they come out clean. An employee grinds the edges of the metal stove parts. He blends in the line created where the two parts of the mold came together during casting. It takes 40 parts to make one woodburning stove, and each one is cast in a sand mold made from a pattern. Next, a worker drills threads for the bolts that will hold all the parts of the stove together. Once the surface of the parts has been prepped, they spray an enamel coating onto them and bake it on. A laser then cuts out a steel heat shield for the back of the wood stove. The intricate cuts are computer driven. An employee bends the heat shield to fit the stove. Next, a worker packs a kind of mortar into a silicone mold of the firebox. The table its on vibrates to settle the material and eliminate air pockets so the firebox will be able to withstand high temperatures. The shape of the firebox is crucial to the stove's energy efficiency, and so are the holes that have been molded into it. These strategically located holes will introduce fresh air to burn gases that would otherwise go up in smoke, preventing energy loss and pollution at the same time. The parts have all been fabricated, and they're ready to put the pieces together. They assemble the stove from the bottom up. They bolt the parts and seal the joints to make them airtight. The assembly takes about an hour. This cast-iron stove is now ready to keep these fires burning for many years to come. An ultralight aircraft is a lightweight, motorized flying machine that looks like a hang glider. Hang gliding inspired the invention of ultralights back in the late 1970s. The idea was to create a slow but affordable method of motorized flight subject to minimal aerospace regulations. They're called ultralights or microlights. This made-in-france 2-seater model weighs about 485 pounds. To be classified as an ultralight by the international air sports federation, takeoff weight can't exceed 990 pounds and minimum speed can't surpass 40 miles per hour. The wing surface, called the sail, is made of a sturdy polyester-based material treated with a special coating that protects it from the sun's ultraviolet rays. They unroll different colors of this fabric onto a cutting table marked with patterns for the four separate sail sections. They staple the fabrics to the table to hold them steady while tracing the patterns. Once they finish tracing, they cut out the pieces, then connect them with double-sided adhesive tape to position them correctly for sewing. They reinforce select areas with adhesive-backed polyester mesh fabric. Then a sewer stitches the pieces together with high-strength, u.v.-resistant thread. In this first stage of the sewing process, they stitch together 1/4 of the sail at a time. In the second stage of sewing, they sew together the top and undersurfaces of each side. Then, in the final stage, they stitch the right and left together. In another part of the factory, the body of the aircraft begins taking shape. It's called the trike because it sits on three wheels, like a tricycle. They build it in sections, welding together several stainless-steel tubes. After the sections receive a baked-on coat of paint, workers assemble them to each other around the fuel tank. The 17-gallon tank is made of lightweight polypropylene, a type of plastic that's u.v. resistant and impact resistant. Once the trike is fully assembled, they mount the three small wheels, similar to those on motorized scooters. Next, they bolt a 100-horsepower gasoline engine, similar to a full-sized motorcycle engine, to the back of the trike. On the front of the trike, they install pedals for propelling the craft on the ground... And a motorcycle-style plastic console with windshield. The console houses the instrumentation panel. They mount the radiator in the center of the trike, cover it with foam and fabric, then install a pair of upholstered seats for pilot and passenger. Then they protect the engine with a plastic housing. They mount an aluminum- and-carbon-fiber propeller on the shaft of the gearbox connected to the engine. Now for the wing. Its main structure is made up of hinged aluminum tubes which fold for transport. Aluminum is lightweight and rustproof, which is essential for flight. They slip the sail over the tubing, then unfold the wing. Thin aluminum tubes provide crosswise structural support. A system of cables keeps the wing in the open position. Another system of cables, called the corset, manipulates the billowing of the sail. This enables the pilot to alter the aerodynamics to increase or reduce speed. Under the wing, they install the a-frame, the ultralight's steering mechanism. The pilot manipulates the a-frame with a horizontal bar, changing the trike's body position under the wing. The last step is to bolt the front of the trike to the wing and hook up the safety backup cables. The pilot steers the ultralight by weight-shifting with the a-frame bar, tilting the trike toward the front to descend, to the right to veer right, and so on. Typical cruising speed is around 75 miles per hour. With an open cockpit, air temperature and oxygen levels limit how high an ultralight aircraft can fly. Maximum altitude is about 3,300 feet, high enough for a thrill ride yet still low enough for a spectacular view. After a busy day of skiing and snowboarding, ski slopes get worn down and develop ruts, bumps, ice, and bare spots. Ski resorts typically refresh the slopes overnight by grooming the snow with specialized track machines. By morning, the runs are as good as new. A snow groomer is like a bulldozer on tracks, except instead of pushing dirt, it pushes snow. It uses grooming implements mounted to the front and back. To build a snow groomer, workers begin by aligning front and rear frames with the vehicle's main frame with the help of positioning jigs. Then a welder gets to work. First, he tacks everything together. Then, with a mechanical lift, he raises and tilts the tacked frame to gain access from various angles. After welding on additional parts, including 10 axles, they prime and paint the frame. Then a mechanic installs a heavy-duty suspension system designed to automatically adapt to the type and shape of terrain, maximizing traction. Next, he greases the 10 axles and installs a wheel hub and bearings on each one. He then mounts the wheel, tightening the bolts to a specified torque to ensure optimal performance and durability. Meanwhile, another mechanic installs the hydraulic hoses. These control the grooming implements and the sprocket on which each track turns. Then he connects the hoses to the main hydraulic valve. At another workstation, a mechanic assembles the diesel engine, the transmission, and four hydraulic pumps. Two of these pumps drive oil to the hydraulic motors, which propel the vehicle forward and backward. The two others pump hydraulic fluid to operate the implements and the cooling system. They lower this assembled unit into the frame and make the required electrical and hydraulic connections. Meanwhile, another team prepares the next unit, starting with the cooling system, two powerful fans which cool the engine and hydraulic fluid. Next, they install the exhaust system and two batteries to power the engine. They mount this assembled unit above the transmission and make all the necessary connections. They lower the cab onto the frame, connect more electrical and hydraulic lines, and fill all systems with their respective fluids. The vehicle now undergoes extensive testing in a dynamometer, which operates the engine and hydraulic components at maximum capacity. If all systems perform according to engineering specifications, the vehicle gets the go-ahead to receive the snow-grooming implements. The rear implement is a tiller, which breaks up the snow into small particles and shapes narrowly spaced parallel lines on the trail surface. A powerful, built-in hydraulic motor spins the steel-toothed rotors at speeds of up to 1,350 revolutions per minute. This ensures even grooming throughout. The groomer's tracks are made of ultra-durable steel. A mechanic guides the edge of each track onto a high-strength urethane sprocket bolted to the rear of the frame while another mechanic slowly drives the vehicle forward to pull the track over the wheels. Then they clamp the two ends together and join them with giant hinges, closing the loop. It's time to mount the snow-grooming implements. They attach the tiller to the rear mechanism, which carries the hydraulic connections for the implement's onboard motor. They attach a blade to the identical front mechanism. The blade plows snow and sculpts features such as half-pipes, those giant, u-shaped bowls of snow in which freestyle skiers and daredevil snowboarders ride. For safety, the cabin has a steel skeleton with roll-over protection features. A specially designed joystick gives the driver precision control over the blade and tiller. The state-of-the-art electronics include three computers, which enable the driver to select and adjust different functions and modes, all of it displaying on a color monitor. The vehicle never sinks into the snow because its weight is optimally balanced on the tracks. This 22,000-pound snow groomer actually exerts less pressure on the snow than a single person does on foot. The rubber band was invented in england in the middle of the 19th century. The key to its success, of course, is flexibility. A rubber band can be stretched around items of various shapes and sizes to hold them together, so in the rubber-band industry, the possibilities for expansion are numerous. Rubber bands come in handy for a whole bunch of things. If you have a bunch of anything, a rubber band can keep it together. Production of rubber bands starts with natural rubber. These spongy slabs have been made from the sap of rubber trees. Natural rubber has greater elasticity than the synthetic kind, making it a better choice for rubber bands. A worker measures and pours rubber processing oil into a kneader machine. He adds powdered pigment--  in this case, yellow and white for a pale yellow shade. He feeds several rubber slabs to the kneader's spiral-shaped jaws. The spiraling blades intersect to break up the rubber and blend in the other ingredients. The kneading process generates heat which softens the rubber, making it easier to form into dough. The kneader spits out rubber-dough chunks. Next, a giant rolling pin transforms the dough into wide, thin pieces. He slices the strips and bundles them. In this form, it will be easier to control the weight of the rubber in relation to chemicals that are added next. They roll the rubber with a precise amount of sulfur and other chemicals that strengthen the rubber and make it more elastic. They then roll the rubber very thin. A worker twists and cuts it into small bundles that fit into the opening of an extruding machine. It forces the still-warm and malleable rubber through dies to shape it into long, hollow tubes. The extruder injects air and talcum powder into the tubes to keep the walls from collapsing and sticking together while warm. The tubes cool down in a trough of water, and they deflate as the injected air dissipates. Next, these aluminum poles will serve as molds for the tubes during curing, giving them the correct shape and diameter. The worker slides the tubes onto the molds. The talcum powder injected into the tubes during their extrusion will also act as a release agent, keeping them from sticking to the molds during curing. They load the tubes into a steam oven, and the intense heat vulcanizes the rubber to boost its tensile strength and elasticity. Out of the oven, workers inject air between the tubes and the molds, making it easier to peel the now-vulcanized tubes off. They rinse the rubber tubes to remove talcum-powder residue. There's so much that the water turns milky white. They hang the rubber tubes to drain away some of the water. By the time they're ready to cut, they're a bit too dry, so a worker splashes water onto them. With the tubes moistened, the next operation will run more smoothly. He feeds several tubes at once to a rotating blade which carves them. This creates elastic bands that are exactly the same width. In this case, that's 1.5 millimeters, an average thickness for a rubber band. With this system, they can cut 1/2 a million rubber bands in an hour. It doesn't take long for the inventory to pile up. There are millions of rubber bands here. A worker scoops them up and examines each one for defects. Once approved, all that's left is the packaging. The rubber bands ride a conveyor that releases them in increments into plastic bags. It has taken about three hours to produce this bag of rubber bands. On a normal day, this factory generates 40 million elastics. That's a lot by any stretch of the imagination.