What is soldering?
Soldering is the process in which two metals are joined together by means of a third metal or alloy having a relatively low melting point.
Soft soldering is characterized by the value of the melting point of the third metal or alloy, which is below 400°C. The third metal or alloy used in the process is called solder.
Soldering is distinguished from brazing by use of a lower melting-temperature filler metal; it is distinguished from welding since the base metal is not melted during the joining process. In a soldering process, heat is applied to the parts to be joined, causing the solder to melt and be drawn into the joint by capillary action and to bond to the materials to be joined by wetting action. After the metal cools, the resulting joints are not as strong as the base metal, but have adequate strength, electrical conductivity, and water-tightness for many uses. Soldering is an ancient technique that has been used practically as long as humans have been making items out of metal.
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What is Tin?
Tin is a chemical element in the periodic table that has the symbol Sn (Latin: stannum) and atomic number 50. This silvery, malleable poor metal that is not easily oxidized in air and resists corrosion is found in many alloys and is used to coat other metals to prevent corrosion. Tin is obtained chiefly from the mineral cassiterite, where it occurs as an oxide. It can be alloyed with copper to make bronze.
Tin is a malleable, ductile, highly crystalline, silvery-white metal; when a bar of tin is bent, a strange crackling sound known as the "tin cry" can be heard due to the breaking of the crystals. This metal resists corrosion from distilled, sea and soft tap water, but can be attacked by strong acids, alkalis, and by acid salts. Tin acts as a catalyst when oxygen is in solution and helps accelerate chemical attack. Tin forms the dioxide SnO2 when it is heated in the presence of air. SnO2, in turn, is feebly acidic and forms stannate (SnO3-2) salts with basic oxides. Tin can be highly polished and is used as a protective coat for other metals in order to prevent corrosion or other chemical action. This metal combines directly with chlorine and oxygen and displaces hydrogen from dilute acids. Tin is malleable at ordinary temperatures but is brittle when it is heated.
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Who first used Tin?
Tin (Old English: tin, Old Latin: plumbum candidum, Old German: tsin, Late Latin: stannum) is one of the earliest metals known and was used as a component of bronze from antiquity. Because of its hardening effect on copper, tin was used in bronze implements as early as 3,500 BC. Tin mining is believed to have started in Cornwall and Devon (Dartmoor) in Classical times, and a thriving tin trade developed with the civilizations of the Mediterranean. However the lone metal was not used until about 600 BC. The last Cornish Tin Mine, at South Crofty near Camborne closed in 1998 bringing 4,000 years of mining in Cornwall to an end.
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How is Tin Mined?
The simplest and earliest form of mining, known as ‘streaming’, simply involved collecting alluvial tin from stream and river beds, and required no complex tools or technology. Open cast mining followed, around the 16th century, and involved the digging of large trenches along the ‘lodes’, or veins of tin ore. Evidence of this early form of mining is evident on Dartmoor in the form of gullies and overgrown spoil heaps. Once gathered, the natural ore needed to be smelted to create ‘white tin’, which generally took place in a building known as a blowing house.
Underground mines didn’t appear until the 18th century, and in an area as waterlogged as Dartmoor, these were fraught with danger. Flooding occurred regularly, so waterwheels were often used to power pumps.
Man-made water channels called leats were dug to direct water from streams and rivers, following the contours of the hillsides, to the waterwheels. Many of these can be seen today, often still flowing with water.
The discovery of tin in the ‘new world’, particularly in the southern hemisphere, had a major impact on the Dartmoor industry, and many miners emigrated. The last tin mine on Dartmoor finally closed just before the Second World War.
The impact of mining on the landscape is still clear to see. Walkers on the moor will often stumble upon ruined blowing houses and mortar stones, featuring rows of semi-circular depressions, in which the ore was crushed. Many of the later mine shafts have now been filled in, but a few do still remain, fenced off to prevent walkers or animals from falling in.
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Who made the first models?
Model-making is as old as civilization. Scale models of buildings, boats, and furniture were buried in tombs of ancient Egyptians to represent possessions the dead took into the next world. Many ancient models survived in the tombs while the original objects did not; these have given historians an understanding of what life in ancient civilizations was like. During the Napoleonic Wars (1799-1815), French prisoners of war carved beautiful model warships from wood scraps; these models are so detailed that they have become documents of warfare and ships lost at sea. They are also highly prized today among antique collectors.
During the Industrial Revolution of the eighteenth and nineteenth centuries, inventors of new tools, machines, artworks, and other objects began by building models of their ideas. Industrial technology was found to have its own beauty, and large machines like locomotives were admired and copied in miniature. Early in the twentieth century model ships and airplanes were sold in kits. Balsa wood pieces were machine-cut to fit together easily and could be painted and rigged like the originals, although they were fragile. In the 1920s, some firms produced scale models of their products out of metal and wood as promotional models. Citroen, the French car manufacturer, produced delightful models that are now valued collectibles.
World War II moved modeling into a full-scale industry and hobby for two reasons. First, plastics were invented and perfected during the years before and during the war. Their versatility made them ideal for mass-produced model kits. Second, the machines of the war stimulated the public's interest in modeling. Slim fighters and heavy bombers intrigued many hobbyists who saw the real aircraft flying overhead on the way to war. The exploits of navy ships, both small and large, in the Pacific also fired imaginations. When soldiers and sailors returned home, they had more time and money for recreation, including building models of the machines they knew so well. Monogram Models introduced its first kits of warships in 1945.
The returning war veterans were also able to afford the automobiles that rolled off Detroit assembly lines; they also built models of the cars they owned—and the ones the dreamed of. In 1951, Revell introduced its first all-plastic model kit of an early automobile: a classic 1910 Maxwell, in which the driver was a scaled-down version of radio comedian Jack Benny. By the mid-1950s, more detailed kits and models that could be customized appeared. By the 1960s scale modeling was a full-fledged hobby with thousands of models covering hundreds of subjects. By 2000, the scale-model industry had produced more automobiles than all the automotive giants of Detroit combined.
In the 1960s, the scale-model industry expanded into ancient history and science fiction. Models of dinosaurs that once roamed the earth, monsters like Godzilla, superheroes like Superman, television characters like the Lone Ranger, and celebrities like Elvis Presley were mass-produced in scale form. The scale-model manufacturers also provided outlets for the public's interest in the Space Race during the 1960s, and models of the newest spacecraft were often on the hobby store shelves before the real-life vessel had taken flight. Fantasy followed here, too, with models of starships and intergalactic craft that have flown on television and in the movies. As techniques for precision casting of true-color parts continued to improve, scale models became important teaching tools. Detailed anatomical figures that can be snapped apart and reassembled are members of many classrooms, as just one example
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How do I clean my Tin models?
Using and soft cloth just dampened with distilled water will keep your models clean. Also some of the commercially available home dusting products that are primarily special designed cloths without any moisture work well too. Just be careful not to snag some of the more delicate parts and pull or deform them.
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I live by the ocean. Can my models stand the sea air without rusting?
Yes, the Tin has some natural resistance to corrosion but the application of the decorative paint finish will be enough to keep your model looking great for years and years.
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