Riva precision manufacturing presents the making of a gold chain bracelet. Before any piece of gold jewellery can be made, pure gold is mixed with a silver alloy in process called graining to create 18 karat yellow gold. The golden alloy granules are poured into a red hot crucible, melted and released into a pan of cold water. When the hot metal hits the water it solidifies again into granules that are now 18 karat yellow gold.
The granules now enter a continuous casting machine that transforms them into cylindrical bars, it works much like a spaghetti maker does, allowing the gold to flow through circular movements. The thick wire is then squeezed through rollers until it gradually becomes close to the desired size for our chain. Rolling the wire hardens the metals, so in order to make it more malleable it is coiled and placed into an oven for approximately 15 minutes. The coil is then dropped into water to quench it and the wire is then pulled through graduated multiple dies to get it to its desired thickness which is a 70,000th of an inch. The wire is softened once again, then fed into a chain making machine. The machine creates links from the wire and connects them together. After the links are connected the chain is coated in solder powder then ran through an oven to solder the links closed. The chain is then polished in a rotating tumbler. A master craftsman receives the chain, cuts it down to the appropriate size and adds on a jump ring on either end and a lobster claw. The jump rings are soldered shut either manually by fire torch or by a laser welding machine. Finally, the chain is hand polished to make it as eye catching as it is expertly crafted. The final product is a 70-5, 18 karat yellow gold chain bracelet. This video shows the technique of using powder soldering to join the links of a newly created gold chain. The chain treated with the chemical soldering powder is run through a kiln which causes the solder to flow and join the ends of the links together. Sometimes this process is not 100% effective and the strength of solder links may not be adequate. A better method, which we employ on all of our handmade gold chains is to laser weld the links individually, this produces a higher quality join with a better visual finish that is stronger than powder soldering. As the gold wire is rolled and pulled through dies, it becomes what is known as ‘work hardened’ and needs to be softened so that it can continue to be worked on. This is achieved by a process called annealing, which is simply heating the gold to red hot for a short period of time and alloying it to cool naturally, or be cooled by plunging it into a bath of water. The gold which starts as a bar and is then worked into a wire will be annealed several times before being turned into the finished gold chain.
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