Office Chairs Vinobrew Reconditioned Sander Drums Lithographs
thomas jefferson, one of america's founding fathers, came up with the first swiveling mechanism for office chairs. Decades later, charles darwin added small wheels, called casters, to his chair to roll it around the study as he worked on the theory of evolution. Today, office chairs still swivel and roll. The office chair has become a status symbol. Executive versions have kingly dimensions. They're extremely plush and have serious lumbar support. Using a hydraulically powered machine, a worker bends 14-gauge steel tubing to form the bottom cushion frame. He joins the ends and welds steel bars to the middle. The bars will support the mechanism for adjusting the position of the seat. He hooks s-shaped steel springs from the front to the back of the seat frame. These sinuous springs will eventually provide a flexible web of suspension in the seat. He positions the rods laterally and clips them to the springs for additional stability and support. The office chair seat frame is now complete. Next, a worker builds the chair's back frame. The frame includes a spine lumbar support, armrest attachments, and other parts. He grinds burrs and other rough spots from the steel. In the upholstery department, another worker smoothes a leather hide so that it sits evenly on the cutting table. He cuts out the patterns following cardboard templates. As he cuts, he works around the natural flaws in the hide, making calculated decisions to minimize waste. By cutting carefully, he'll be able to get all the leather he needs for one chair from this large hide. That's important because color and grain can vary from hide to hide. Using pieces from the same one will give the chair a consistent look and texture. Once all the leather pattern pieces have been accumulated, another worker cuts foam cushioning for backing. The density of the foam in the chair varies. He uses more rigid foam for the chair's contoured cushioning so it will hold its shape. Another worker selects softer foam for the part of the chair that the occupant's back will rest against. He cuts slits into this softer back padding. This creates channels that will ultimately become a design feature. Using chalk, he draws lines onto the corresponding leather that match up with the slits in the foam. A worker aligns the chalk lines in the leather with the slits and puckers the leather as he sews the backing to it. This forms a ribbed pattern in the upper half of the chair upholstery. He stitches the padding flat to many of the other pattern pieces. This particular part is a side panel for the back of the chair. Returning to the upholstery with the ribbing now, he sews contoured casings to each side. To complete the back of the chair, workers add a chipboard panel and encase the structure with foam, then cover it with the leather upholstery. Once the chair seat has been upholstered, an employee installs a plastic cover to enclose the back. He screws a sliding plate to the base. This mechanism will work in conjunction with the plate to slide the seat forward and backward, depending on legroom needs. It also has features for adjusting the tilt and height of the seat. The hydraulic cylinder for adjusting the seat height is next. The cylinder also doubles as the chair's stem, and it swivels to allow the seat to rotate 360 degrees. He attaches the aluminum base to the cylinder. He snaps the casters into slots in the aluminum base. He equips the back of the office chair with an automobile-style headrest. The prongs fit into the brackets in the chair frame. Finally, he locks the armrests into the frame. This office chair is now ready to make someone's desk job a lot more comfortable. Vinobrew is just what the name implies-- vino, meaning wine, and brew, referring to beer. This hybrid beverage is part of a fledgling trend by some adventurous breweries and wineries to merge their two otherwise separate worlds of alcohol and create a unique drink. This vinobrew is made from port-style sweet wine, dark strong beer known as stout, and another ingredient that's brewed-- coffee. This concoction is the collaborative creation of a winery, microbrewery, and coffee producer. The microbrewery grows some 20 different varieties of hop plants whose flowers contain the resins and essential oils that give beer its bitter and aromatic characteristics. To begin the beer-making process, the brewmaster fills a tank, called a mash tun, with water, then ignites a burner. When the water heats to around 150 degrees fahrenheit, he pours in a blend of different types of malts. Malts are cereal grains such as barley or corn which have been soaked to kick-start germination, then, once sprouted, dried with hot air to halt germination. Stirring the malt into the hot water activates enzymes that convert the starches in the grain into fermentable sugars. After an hour or so, he transfers just the liquid, called wort, to the boil kettle and gradually adds different varieties of hops. He brings the wort to a boil to kill off bacteria and sterilize it. Next, he cools the wort and transfers it to the fermentation tank. Then he adds yeast. Over the next 10 to 14 days, the yeast consumes the fermentable sugars in the wort, converting them into alcohol and producing carbon dioxide gas, which creates bubbles. This process transforms the wort into beer. At the coffee company, the hot coffee beans must be cooled quickly after coming out of the roaster so that they don't overcook. This perforated cooling pan stirs the beans to help dissipate the heat, then a commercial coffee grinder grinds the beans into coarse-ground coffee. To prepare coffee for the vinobrew, a worker puts grounds into a filter bag, saturates the bag with cold water, then submerges the bag in water, letting the grounds soak for about 16 hours. Then he pours the coffee into a large jar. At the winery, winemakers harvest and press the grapes, add yeast and ferment them, then age the port wine for at least 2 years in oak barrels. To prepare to make vinobrew, the winemakers test samples from different barrels for acidity and sweetness to help decide which wines to potentially use. The winemaker and the coffeemaker then experiment with amounts of those wines and different cold-brew coffees made from various types of beans. The brewmaster also joins in, measuring out beer. This process is as much art as science. For each batch of vinobrew, the respective makers play with a selection of ingredients and with the proportions, tasting and smelling the samples to evaluate aroma, sweetness, bitterness, and acidity. What they try to create is a harmonious blend of the three elements, a new flavor without the taste of any one element dominating the others. Once they pin down the winning formula, they replicate it on a large scale for production. The winery pumps the selected wine from storage tanks into barrels for transport to the brewery. At the brewery, the brewmaster pumps the required amount of wine from those barrels into a blending tank. He pours the required amount of cold-brewed coffee into the blending tank. Then he pumps the required volume of beer into the tank. Beer makes up the largest proportion of the recipe, followed by wine, then coffee. After blending the ingredients in the tank, the brewmaster pumps the vinobrew into a beer keg. Then he injects carbon dioxide gas to add more carbonation. When you pour a glass of vinobrew, the bubbles rise to the top, producing foam known as beer head. But while this might look and feel like regular beer, one sip tells you that vinobrew is uniquely different. To refinish a hardwood floor, one has to sand it with a floor-sanding machine. After a few thousand hours of operation, the machine's drum, which drives the sandpaper, wears out. The contractor can either replace it with a new one or send the worn one out to be reconditioned. This company specializes in reconditioning worn sander drums, that means restoring them to like-new condition. A drum can be reconditioned as many as eight times before it has to be replaced. The first step is to grind off what's left of the aluminum drum's worn rubber surface. It gets worn down due to the drum rotation speed of up to 2,600 revolutions per minute and often gets damaged by running over protruding nails or carpet tacks. A worn drum doesn't hold the belt of sandpaper taut, which causes the machine to slip to the left and right, rather than sand smoothly in a straight line. A worker places the drum on a press to detach the arbor shaft, which attaches the drum to the sanding machine. When the drum was new, its aluminum sides were freshly painted. That paint is now mostly worn away. Sawdust and rubber residue fill the drum's nooks and crannies, so a worker places the drum inside a sandblast cabinet and puts his hands through gloves that reach inside. He holds the drum in one hand, a sandblasting nozzle in the other, and in a few minutes, the drum is pristine. But it still has an ever-so-thin layer of rubber remaining, so another worker mounts the drum on a lathe and shears off the rubber with a knife. Then he passes the knife again, removing a mere tenth of a millimeter of aluminum. This exposes a new smooth aluminum surface. Then a worker cuts a sheet of brand-new rubber to the exact length needed to cover the circumference of the drum. The rubber is nearly two-thirds of an inch think, roughly twice the thickness of the worn layer they grinded off. After clamping it down flat, the worker applies an adhesive designed for rubber. Then he sprays an accelerant onto the drum's primed surface to strengthen its bond with the rubber. He lets the accelerant dry for 6 hours, then spreads a second coat of adhesive on the rubber and wraps it around the drum. Twenty-four hours later, with the adhesive cured, another worker mounts the drum on a lathe and trims off the excess rubber from both sides. He then sands the trimmed edges to make them perfectly flush with the sides of the drum. The drum goes back on the grinder now to finalize the overall diameter of the drum. Using a ruler, a worker adjusts a measuring instrument, called a caliper, to the diameter measurement. He then grinds down the rubber a bit at a time, spot-checking with the caliper regularly. The worker stops grinding once the caliper check tells them the drum diameter is correct. If a sanding drum isn't perfectly balanced, it vibrates and disfigures the floor, so a worker mounts the drum on a balancing machine. He applies a band of masking tape and draws a black line on the tape to give the machine a reference point from which to start measuring. As the machine rotates the drum, a sensor measures velocity on both sides simultaneously. If the velocity is inconsistent on either side, he balances the drum by adding or reducing weight on the problem side. To reduce weight, a worker drills a hole to remove aluminum. To add weight, he fills the drilled hole with tin, a metal that's far heavier than the aluminum he removed. The final step is to repaint the sides. A worker masks the rubber with a template then sprays the aluminum with rust-inhibiting metal paint. Now this main component of a floor sander is as good as new, ready to bring a worn wood floor back to life. Lithography was discovered when german playwright alois senefelder had no paper handy for writing a laundry list. So he wrote it down on a stone using a grease pencil and stumbled onto a new method of printing, one that relies on the chemical aversion of grease and water. Lithographs can rival paintings for detail and mood. They have a unique visual quality, and that's why making them hasn't become a lost art. A lithograph starts with a flat limestone slab. The artist confirms the same thickness all the way around the slab. She now resurfaces the stone using a grinding tool called a levigator. She wets down the surface of the stone and the levigator to allow the levigator to move freely across the stone during grinding. The artist sprinkles silicon carbide grit on the stone. She spins the levigator across the stone and, together with the grit, it grinds off the top layer. This process removes the previous drawing and preps the stone for the next one. She finishes the grinding with a finer abrasive to give the limestone a smooth finish. Once the residue has been rinsed off, the stone is ready for a fresh image. She brushes a natural gum, called gum arabic, around the edges, creating a border that will be receptive to water but not the printing ink. This process makes a non-image area. The artist marks up a piece of paper with a crayon made of wax, charcoal, and clay. She places the paper on the stone, crayon-side down, and sets a drawing upside down on top. She tapes the drawing to the stone. She now follows the lines of the figure on the paper with a pencil, pressing firmly. This transfers the drawing to the stone and creates a reversed image on it. The artist simulates specks of snow, with a technique called stippling, with gum arabic and a brush. She fills in the drawing using a greasy crayon. The stone picks up and holds the greasy substance. These crayons come in varying degrees of hardness. Once the artwork is complete, she dusts the image with rosin which is a tree sap powder, followed by a talc powder. This will ultimately protect the image during etching. The artist then brushes gum arabic onto the art to protect the stone from the corrosive nature of the etching material, a mix of nitric acid and gum arabic. This mixture alters the surface of the stone so that the image areas will attract ink, and the non-image areas will repel it. She places a sheet of paper on the print stone and applies lubricant to the bottom of the scraper bar on the press. She spreads more lubricant onto a tympan, a thin sheet of durable plastic, that she's placed on the paper-covered print stone. This allows the stone to slide under the pressure of the press. The artist moves the sliding press bed forward so that the lithography stone sits directly under the scraper bar. She turns the mechanism to tighten the bar to the stone. She moves the press bed forward to test the pressure of the scraper bar. She confirms that the pressure is sufficient for printing but not too tight. Satisfied, she removes the tympan. She washes the crayon from the stone using highly refined mineral spirits. What remains is a ghost of the image. The artist then rubs a petroleum-based substance onto the stone that will serve as a base for the ink. The substance attaches to the image on the stone. Using a big leather roller, she picks up oil-based ink. An assistant dampens the stone with a wet sponge. The artist transfers the ink to the damp stone. The greasy parts of the stone pick up the ink while the wet parts don't. The assistant moistens the stone again. The artist places a sheet of print paper cut to size over the image. She covers the stone with clear plastic tympan. The press bed rolls forward until the stone sits directly under the scraper bar. The preset bar applies the exact pressure needed to print the image onto the paper. The artist carefully lifts the paper, revealing a perfect mirror image of the art. Using the same stone, she can make hundreds more, each one a work of art.