Table Tennis Tables Plastic Model Kits Light Microscopes
Table tennis is more commonly known as ping-pong. Folding table-tennis tables are popular in homes and kept outdoors because they can be closed up and rolled out of the way. These tables can also fold down on just one side, allowing for solo play. This high-end outdoor table-tennis table has an aluminum bottom that prevents the tabletop, called the plate, from warping or splitting due to expansion and contraction. A press stamps cups into a sheet of aluminum. This pattern creates nearly equal areas both in contact and out of contact with the rest of the plate layers, providing flexibility to withstand temperature-related movement. Each table needs two embossed aluminum sheets-- one for each half of the plate. A technician assembles frames for the plate halves out of square extruded aluminum tubes, cut to the lengths and widths of the plate half perimeter. An automated milling machine makes miter cuts, which allow the tubes to be made into rectangles. Then, the technician moves the frames onto a rotating fixture... And welds the corners together. The frames are inserted into a brushing machine. Inside, wire brush rollers allow the aluminum surface to become rough. This helps the components to adhere to one another. Another technician places the embossed aluminum sheet into a rectangular assembly jig. And adds the brushed aluminum frame. A conveyor transfers the jig to the next station. Then, the jig connects with an 8-millimeter-thick sheet of particleboard, made of wood chips and glue. The board is coated with a heat-activated adhesive film on both sides. At the next station, an aluminum sheet is placed on top of the particleboard. This step completes the plate component assembly. Next, the conveyor loads the jig into a press. Once 12 jigs have been loaded onto the press, it heats to 239 degrees fahrenheit. And compresses them for about 10 minutes. This process activates the adhesive and bonds the components of each plate into a single unit-- one framed plate half. Each plate half goes through an automated milling machine. The machine trims any excess material from all four sides to ensure the table won't have any sharp edges. The plate half goes through a paint machine, then into an oven. The process repeats, applying a second coat of paint and a u.v.-resistant clear coat. A machine applies paint through a screen stencil, printing the lines that mark the boundaries of the playing surface. After the paint is dried in an oven, a team places the finished plate half in a cardboard box and attaches folding legs to the base. The factory mills the legs in-house out of high-tensile steel, then finishes them in baked-on paint. The net, along with several components, are packed and made in-house, which the consumer later assembles to the table. Components include the net posts, side panels, wheels, wheel brakes, and the ball return box. Finally, the plate half is transferred to an automated system, which completes the packaging. Many ping-pong tables on the market require the net to be removed every time you fold the table. The design of this table enables the net to remain in place whether the table is folded for storage or has one or both sides open for playing. Less setup time means more time to play. Plastic model kits were developed before world war ii, when people became interested in seeing machines in small-scale replication. Today plastic model kits continue to offer building opportunities to hobbyists, who love the challenge of putting little pieces together. With a plastic model kit, a colossal ocean liner can be replicated in small scale. Built with nearly 2,000 pieces, assembly is all about the details. Each model kit starts with extensive research and design, a process that can take up to a year to complete and cost up to $100,000 dollars. Using the computer design, a set of steel molds is made for every piece of the kit. Tools carve into steel chunks to make the molds. Precision work done entirely by machinery. Installed in large dies, the molds are linked by channels. Melted plastic will flow through the channels to fill the molds. Clear polystyrene is used for transparent components. The melted polystyrene is pumped under high pressure into the molds. Once the plastic hardens, a pusher ejects the parts. The connected kit parts are known as a tree. The opaque polystyrene pellets are used to form the other kit parts and are molded separately. The scale of the parts is 1 to 24, which means the model will be 1/24 the size of the original. Since the manufacturing is automated, the risk of contamination is reduced. Next, the tree is put through a technical analysis test. The technician photographs the tree and compares it to an image already fit to scale. If some parts haven't taken shape or if they're only partially formed, more pressure may be needed to ensure that the polystyrene flows into all the mold cavities. A technician compares a randomly selected tree to the design and verifies that no parts are poorly formed or missing. Once the confirmation is attained, the technician slides the model kit parts into a clear plastic sleeve. Before it's ready for retail, the kit needs a set of illustrated instructions. The designer deconstructs the model and then reconstructs it on his computer as he draws up the instructions. With the instruction manual complete, a team packs all the components of the model kit in a box. One of each of the kit trees is placed in each box. The kit also includes decals and large, separately molded parts, like the ocean liner hull. A technician closes the box. As it moves down a conveyor, a laser prints the date of production and the batch number on the side. Then, the box is wrapped in plastic, and the ends are sealed with heat guns. A year of planning has gone into making the plastic mold kit. But took less than 10 minutes to mold the kit parts and package them. Building the model will take 10 to 12 hours. The factory does a test build on each model to confirm that it comes together as planned. This is the iconic constellation aircraft, a world war ii military transport plane that was later converted to a commercial airliner. Assembling a plastic model kit can be a great learning experience for the builder. Decals mimic the i.d. information on the outside of the original aircraft. These decals have been pretreated with adhesive. Soaking the decals in water activates them. The assembler brushes more water onto the design spots on the model. And applies the decals to the dampened spots. As the glue dries, they adhere to each other. The plastic models can also be painted beforethe decals are applied for refined and clean look that really comes together. The light microscope was invented in 16th-century europe. It allowed the human eye to see tiny things that couldn't be seen before. A sophisticated research tool with focused light and optical lenses, can magnify biological tissue, minerals, and computer chips. Observation is an important aspect of science. The light microscope increases the power of observation, making it possible to see things that can't be seen with the naked eye. This 19th-century microscope represented a turning point, with lenses that delivered more light to specimens, increasing resolution. A light microscope often has multiple lenses, all made from special optical glass. A drill with a core bit tunnels into the glass to produce several solid cylinders. The drill cuts them larger and thicker than the final specifications. This gives technicians extra material to work with. A tool moves the cylinder against a spinning blade slicing it into lens blanks. The cylinder is first glued to a glass block, then glued to the tool. This method holds the cylinder in the correct position. Since bits of glue are left on the lenses, a thorough washing removes them. Next, a device grips the lens using vacuum pressure and angles it for grinding. Multiple grinding tools remove any excess glass and shape the radius of the lens. In a process known as lapping, a technician applies a fine abrasive compound to a bowl with the desired contours. He rotates and rubs the lens against the bowl to further shape the lens. He rinses off the lens and holds it against a light while he examines it for scratches. He measures the radius of a master lens and compares it to that of the lens he's been working on. If the measurements are off, he'll remove more material. Once additional material is removed, he measures the thickness of the lens and compares it to what it was before the adjustments. Next, these polishing tools will be used to fine-tune the profile of the microscope lenses. To protect the lenses during polishing, a technician sprays on a temporary lacquer. These tools will remove just a fraction of a millimeter of glass, but it will make an important impact. Polishing liquid provides fine abrasion and enables the tool to move across the glass. Then, a robot trims the edges of the lens. A device clamps the lens in place as trimming continues along the edges. Trimming allows the lens to reach the correct diameter. Next, the lenses are cleaned in multiple water-based solutions. In the baths, the vibrations from high-frequency sound create a gentle scrubbing action. The intensive cleaning leaves the lenses pristine. A technician places the freshly cleaned lenses in round trays. She handles them very carefully inserting them individually into each tray slot. Because they're extremely fragile, the slightest pressure could crack them. The lenses in the trays will receive an antireflective coating-- one that will prevent a loss of light due to reflection. Next, the antireflective material is loaded into a coating machine. The technician adds a specific amount of magnesium fluoride into a receptacle in the base. She inserts a piece of aluminum oxide in the next receptacle. And transfers the microscope lenses to the chamber, placing the rack on top. Inside the chamber, heat and a targeted plasma beam evaporate the materials. They precipitate onto the lenses, forming a coating. Coming up, all is revealed as the lenses come together in the microscope. Light microscopes bring the invisible into focus. Similar to telescopes, a tiny specimen is placed under the lens assembly, from which the viewer can discover what lies within. By magnifying the minuscule, the light microscope has become an indispensable scientific tool. The light microscope often has multiple lenses. Throughout the production process, the lenses are put under the microscope to confirm that the geometry is correct. A technician magnifies the lenses one at a time, measuring their radius and the diameter. Meanwhile, computerized tools shape the edges of glass prisms. The prisms are triangular lenses that bend or refract light, aligning colors at a focal point for a clearer image. Once the shaping is complete, a technician positions a prism on a holder to be calibrated. She aims a laser at it. The light passes through the prism, reflected in a mirror, and bounces back. A computer magnifies the surface of the prism a thousand times bigger than its original size, measuring the degree to which the prism refracts light and the flatness on each side. This is an inside look at a microscope lens assembly, revealing the combination of lenses. A prism can be an important part of this combination. The cast-aluminum housing has been equipped with the circuitry. Some of the connections have already been made. It's ready for the focusing mechanisms that allow the user to zoom in on tissue or other specimens. A technician inserts the motorized focus drive into the housing so that the ends protrude from both sides. He attaches adjustment knobs to the ends. The larger part of the knob is for quick motorized focus. The small one is for slower and more precise focusing. He slides a protective rubber cap onto the fine-focus component of the knob. Another technician mounts a system for revolving lenses to the microscope. This is called the nosepiece. He wires the nosepiece to the controls. Using compressed air, a technician cleans a part known as the side port revolver. It's equipped with a mirror, prism lens, and a magnifying lens. It will reflect light to the lenses in the eyepiece or external cameras. Then the side port revolver is tested. At this point, multiple lenses have been installed in the tube lens assembly. The technician screws the assembly to a revolver. Light from the illuminated specimen shines through the tube lens in parallel rays the rays are projected onto the eyepiece or external camera. He looks through the eyepiece to check the positioning of the lens in the revolver slot making adjustments if needed. A reflected-light illumination system is installed. This part directs light through the lens and onto the specimen, then back through the lens to the eyepiece or external cameras. This system makes it possible to magnify opaque specimens. Then a technician installs the transmitted light arm. The light arm is used for magnifying transparent or thin specimens. It does this by directing light through them. A technician performs a final inspection. He places specimens under the microscope, checking the brightness of the transmitted light and the resolution of the magnified image. He tests the focus of all the lenses in the nosepiece to confirm that each one delivers a sharp, clear view. He verifies that the revolving mechanisms move smoothly and are in good working order. After this final inspection, this light microscope is ready for research. By imaging small things, big discoveries are possible.