Carbon Fibre Antique Frame Restoration Railcar Movers Hood Ornaments
Carbon fiber is an engineer's dream-- lightweight yet incredibly strong. It's a string with thousands of parallel filaments. Multiple strings can be twisted into yarns, woven into fabrics, or molded with resin to produce materials called carbon-fiber composites. Carbon fiber is five times stronger than steel yet less than half the weight. To make it, they take a plastic fiber composed of thousands of filaments far thinner than human hair. They then chemically alter it to form a perfect chain of carbon atoms for the final product. This mammoth machine lines up dozens of those fibers which then travel through an oxidation oven for a couple of minutes. The oven temperature, about 480 degrees fahrenheit, prompts the fibers to pick up oxygen molecules from the air. This rearranges the fibers' atomic structure, rendering them resistant to high heat. As the fibers oxidize, they change color to eventually turn black. They're now primed for the next process, carbonization. Furnaces heat the fibers in an oxygen-free gas mixture. This expels the non-carbon atoms and transforms the remaining carbon atoms into tightly bonded crystals running parallel to the length of the fiber. This gives the fiber its strength. The exiting fibers travel through a bath of electrically charged water that etches the fibers' surface so they'll better absorb resin. The next station applies a light preliminary coat of resin. This will strengthen the fibers' chemical bond to the molding resin. A spooling machine winds each fiber, now referred to as a carbon-fiber tow, onto a bobbin which buyers either weave into a carbon-fiber fabric or mix with resin to mold a product. Another form of carbon fiber is prepreg-- sheets of resin-impregnated carbon fiber ready for molding. It's like ready-to-bake cake mix. The resin is a formula of epoxy and various powdered hardeners and accelerators. Workers pour the resin into a filming machine which spreads it in a thin, wet layer onto paper. The paper is pre-treated with a release agent to prevent the final product from sticking, like spraying a baking pan with non-stick coating. Another machine, meanwhile, groups 200 to 300 carbon-fiber tows into a giant band of fibers called a web. The width and thickness of the web determines the width and thickness of the prepreg sheet. Workers mount two rolls of resin-coated paper onto the resin-impregnation machine. A heating element warms up the web as it enters to facilitate resin absorption. Then the heated carbon-fiber web is sandwiched between two sheets of resin-coated paper. High-pressure heated rollers thin out the resin so it penetrates the millions of carbon-fiber filaments. Cooling plates then turn the liquid resin to gel so that the next station can remove the paper, which pulls off easily thanks to the release agent. The next station covers the top of the prepreg sheet with polyester film. This prevents the prepreg sheet from sticking to itself at the end of the line when it's wound into a roll like a fruit roll-up. In the factory's lab, technicians run quality control tests on prepreg samples. First they weigh the sample. Then they wash off the resin with chemicals and weigh the sample again. This verifies whether the ratio of carbon fiber to resin is correct. The lab also analyzes samples of composite-- carbon-fiber reinforced resin-- in this tensile strength test. The computer measures how much strain the sample withstands before breaking. Such testing ensures the carbon fiber delivers optimum strength, durability, and heat resistance, whether it's used to make an auto part, a wind-turbine blade, or a golf club. Antique gilded frames have spent many years protecting paintings and enhancing them. But over time, grime can obscure the gold-leaf shine and the frame can suffer damage and deterioration. But these frames are highly collectible, and restoring them preserves their value. With elaborate cast ornamentation and gold-leaf work, this 19th-century gilded frame is itself a work of art. But it's in need of renewal. Restoration work done many years ago has cracked, and gold leaf is deteriorating elsewhere on the frame. The technician carefully pries the cracked acorn casting loose and removes it from the frame. He'll make a new one from scratch. It will need to completely fill the empty space and look exactly like the others on the frame. He starts by making a mold with dental impression rubber. He kneads the two putty-like components together to activate the ingredients. When the color's uniform and there are no streaks, the rubber is ready for molding. He must act quickly because in just three minutes the rubber will cure. He presses it around the acorn ornament on the frame to capture the detail. He now has a mold he can use to cast a new ornament for the frame. He'll use this wood epoxy for that. Like the dental impression rubber, it must be mixed thoroughly to activate it. He presses the epoxy into the contours of the mold, pushing it from one end to the other. This will prevent air from becoming trapped in the casting and compromising its integrity. After a 10-minute cure, the epoxy casting is ready, and he extracts it from the mold. He examines the detail and confirms that it is an exact reproduction. Then, using a scoop chisel, he sculpts the edges and the inside of the casting to shape it to the picture frame. In this comparison shot, the shaped part is the one on the left. He places the cast epoxy ornament on the frame and nails it down. The epoxy is still soft enough that he can drive the nail into it without breaking it. He fills the gap between the casting and the frame with more epoxy, providing a seamless transition from new to old. After the epoxy solidifies, he brushes something called bole onto it. Bole is a mix of clay and rabbit-skin glue. It provides a surface that the gold can adhere to, and the rabbit-skin glue will give it flex as the wood expands and contracts. He then transfers the 23-karat gold leaf to the casting. Before he lays each piece of gold leaf, he wets the surface of the ornament with a gilder's liqueur-- a mix of water, alcohol, and rabbit-skin glue. This causes the gold leaf to conform to the contours of the ornament and adhere. After the golf leaf sets for an hour or two, he burnishes it to a very high shine using a tool made from agate, a very hard, semiprecious stone. Hundreds of years ago, craftsman used dogs' teeth for this job. He rubs the shiny, new gold surface with very fine-grade steel wool. This removes some of the gold to simulate natural wear so that it matches the patina of the rest of the frame. And what a transformation this plain epoxy casting has undergone. Newly gilded, and it looks like it's always been part of the antique frame. Other sections of the frame require regilding. He rubs alcohol onto those areas to get rid of atmospheric residue that would prevent the adhesion of the new gold. And after applying gilder's liqueur, he lays sheets of the new gold leaf over the old, working with a steady rhythm to give the area complete coverage. He's aiming for more of a matte finish on this section, so he doesn't polish it. He brushes a protective coat of shellac onto it. He's used a combination of old materials and new to restore this antique gilt frame, and it's picture-perfect. Pushing and pulling railcars at the train yard is the job of a large motorized vehicle appropriately called a railcar mover. It switches the cars from one track to another, shuttles them in and out of the cargo loading area, and positions them in line behind the locomotive. A railcar mover has to drive both on and off the train track, so it has two types of wheels-- four steel rail wheels for guiding it on the track and four wheels with rubber tires for driving on the ground. When building a railcar mover, they start with the frame. A computer-guided plasma cutter cuts out all the frame parts from a 4-inch-thick steel plate. Once all the frame parts are ready, workers begin welding them together. They position the deck plate, the mover's floor, upside down and weld on the frame rails. These will hold the axles for the rubber wheels. Then, to those frame rails, they weld the rail arm mounts. These will hold the rail arms which hold the rail wheels. After welding several additional components to the frame, workers bolt the axles for the rubber wheels to the frame rails... Then the rail arms to the rail mounts. Now the frame goes to the paint shop for a coat of primer followed by a coat of automotive paint. Workers also roll on a textured floor coating to create a non-slip surface for the driver to safely walk to and from the cab. When the paint dries, the frame returns to the assembly line where workers begin mounting the 4.5-foot-wide rail wheels onto the rail arms. After mounting each wheel on the spindle, they install a bearing, then a large nut. They must tighten the nut to the correct torque yet not over-tighten it, or the wheel won't turn freely. Once they've got just the correct torque, they secure the nut with a retaining lock nut. They finish off this installation with the rail-wheel equivalent of a hubcap. This steel cover holds in the grease that lubricates the wheel and bearing while keeping out dust and dirt. Next they mount the four rubber wheels, securing each one with a dozen bolts. These steel wheels with rubber tires are about 6 1/2 feet in diameter. Workers mount several other components, including a pair of air tanks with gauges for the railcar's pneumatic brake system. These are the brakes the driver uses when the mover is coupled to railcars. When it's not, the mover has its own separate hydraulic brake system, the components of which workers also install at this stage. They attach a hydraulic cylinder to the steer axle. This controls the steering of the rubber wheels when the mover is off the train track. The rail wheels, of course, don't require any steering, as they simply follow the track. Now workers install the 300-horsepower diesel engine. It's already bolted to the transmission. Then they hook up the electrical wiring, which connects the engine and transmission to the computer controlling them. They lower the hood over the engine and transmission. The hood has three components already installed-- the engine air intake, air cleaner, and muffler. Finally, they install the cab. It has a steering wheel for driving off-rail and a control console that rotates 180 degrees to let the driver operate at whichever side of the cab provides the best view of all the railcars the mover is pulling or pushing. The finished railcar mover doesn't leave the factory before a burn-in period in the test pit. The test is so intense, the rubber tires have to be cooled with water. Pulling as many as 40 railcars at a time is no job for a lightweight. That's why a railcar mover weighs in at up to 45 tons. At first, hood ornaments were used to beautify external temperature gauges and radiator caps. They then evolved into signature pieces that embodied the car brand. And when the radiator caps were moved under the hood, the ornaments stayed on top. A hood ornament is a little piece of automotive art. Popular mainly on luxury cars now, these ornaments symbolize the spirit of the car and can make quite a statement on the street. Each ornament starts with an aluminum mold that consists of many parts in order to achieve a complex shape. An injector pumps specially formulated wax into the mold cavity. The wax solidifies quickly. The operator dismantles the mold and removes the cast wax model. The detail is impressive. He examines it for flaws. He cools the model in water until the wax firms. This wax model will be used to make a mold to cast the metal ornament using a technique that dates back thousands of years. He attaches numerous cast models to a wax riser by melting the wax a little so they adhere. The next worker then dips the models and riser into specially formulated ceramic slurry. He makes sure that the liquid covers every detail. Still wet, the models then go into the rain sander, so named because it actually rains grit. The grit sticks to the models for a stucco effect. He repeats the ceramic dip and grit process three times to build up substantial shells around the wax models. These shells will serve as molds to cast the hood ornament. In this case, the casting material is steel. They melt rejected hood ornaments with steel chunks to transform them into a white-hot liquid. The ceramic models have by now been cured and the wax melted out. Workers ladle the molten steel into the riser feeder cup. The steel flows into all of the ceramic molds. They top it off with a manganese mixture that catches fire and keeps the steel hot and liquid a little longer, ensuring that it feeds into all of the molds. The steel cools for several hours and solidifies. An employee then breaks open the network of molds to reveal the cast hood ornaments. He inserts a pneumatic hammer into the feeder cup, and it shakes off most of the remaining ceramic shards. This machine blasts off the rest using very fine stainless-steel particles. They're ready to cut the cast ornaments free from the main base. With the riser on its side, the worker slices off one hood ornament at a time using an aluminum-oxide cutting wheel. At this angle, he can't make a clean cut. He leaves a fairly thick chunk on the base. He grinds off that chunk using an abrasive belt. The base of the hood ornament is now smooth and level. Next he refines the shape of the hood ornament. He grinds away excess material to improve the profile of the piece and generally clean it up. This process also adds shine to the stainless steel. To give the hood ornaments a real polish, they plunge them into a sulfuric-acid solution. The solution eats away impurities to expose the nickel. A worker buffs each hood ornament against a cloth wheel until it gleams. He examines his work under a magnifying glass. Defects won't be tolerated, and even at this stage, the statuette could be rejected and melted into a new one. It passes inspection. Made of steel, silver, or gold, a hood ornament on a luxury car is a great way to say you've arrived.