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How to make casting brone sinks:

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Have You Ever Wondered How Cast Bronze Sinks Are Made?
Cast Bronze Sinks Are Beautifully Designed And Will Enhance The Appearance Of Any Home.

Most Our Cast Bronze Sinks Can Be Made Out Of Copper. With Our Copper Sinks We Offer 16 Patina Finishes.

                View Our Large Selection Of Cast Bronze Sinks With Pricing

1. Mold : The original sculpture is created, usually in plastocene, oil clay, polymer clay or various kinds of wax, ours are made of plastocene. All of the designs are the inspiration of the artist creating the mold.

2. Rubber Mold: When the sculpture is completed, it is time for rubber model. The rubber mold has an exterior plaster or fiberglass mold created (aka "mother mold”) to help support the rubber when wax is poured into it. The original sculpture is removed.

3. Wax Injection: A special wax is melted and poured into the mold. The mold is turned to make sure all the surfaces are coated, and then the wax is poured out. The process is repeated several more times until the correct thickness of wax is reached. Larger bronzes are usually hollow, with the bronze about 3/16" thick, depending on the size of the piece. The molds for monumental-sized bronzes are made in small, manageable pieces and the bronze is welded back together after casting.

The process of creating Cast Bronze Sinks is a long one.  That is why Cast Bronze Sinks cost more to make.

4. Pattern Correction: The wax is removed from the mold and cleaned up, removing mold marks and making the piece as perfect as possible. (Bronze picks up every detail, including the artist's fingerprints!) This process is called "chasing" the wax. Sometimes the wax casting has to be cut in pieces for the bronze to pour better. The finished bronze will be welded back together and finished so nicely that you'll never know it started out in pieces.

5. Wax Pattern Assembly: Once the wax mold is completed, it is time for our workers to add “wax spruces” to it. These rods allow the hot air to escape when the bronze is poured, so there will be no air bubbles on the surface of the piece. Other sculptures have the spruces added later after the wax has been cast in the mold. The design of the original sculpture is what determines when spruces are added. The process of adding spruces is called "gating up.”

6. Shell Making: The spruced wax casting is dipped in a liquid ceramic material called slurry. The slurry changes color to indicate when it's dry. Once the wax has been dipped in the slurry, it's coated with ultra-fine zircon sand. This process is repeated several times, with at least two coats of the finest sand as the first layers, to capture all the surface detail. Coarser sand is used for the final layers. The coated piece (which is said to be "invested" -- the slurry and sand are the "investment") is hung to dry.

7. Preheat: Once thoroughly dry, the piece is put in a kiln (oven) that heats to a very high temperature, melting out the wax (thus the term "lost wax process"). The ceramic shell ("investment") is now a cleaned-out mold for bronze.

8. Melting Amd Pouring: Melted bronze is poured into the heated ceramic mold (still warm from the kiln, or heated so it won't crack when the molten metal is poured into it). It is ZCuSn8Zn4 Tin Bronze Alloys (88% copper, 8% Tin and 4%Zinc, lead free) that is equal to ASTM-C 90300 in USA.


9. Shell Off: When the bronze is cool, the ceramic shell (investment) is broken away, revealing the bronze.

10. Surface Treatment And Heat Treatment: The piece is sandblasted to remove every speck of investment. The spruces and pour spout are cut off and the nubs ground down, and any mold marks or other blemishes polished away ("chasing" the bronze). If the sculpture was cut into pieces to be cast, it is welded together and weld marks ground off. The welds create bumps and a dark rainbow hue on the bronze, and these nubs and color are also ground off. At this point, the bronze is a bright brassy color.

11. Polishing: After surface treatment and heat treatment, all bronze sinks will be polished.

12. Patina (acids which color the bronze and help define it) is applied and the high spots of the sculpture often rubbed with steel wool to keep the high spots light. The recesses are left with the majority of the patina and thus help define the shape of the sculpture. Molten clear paste wax is then applied, the piece is mounted on its base, and you have a finished bronze. Another technique we use to make the patina is: to bake the finished bronze items in the kiln with about 500—600 cent degrees, the most beneficial thing is that the patina will last very long and is quite hardy.

Care And Maintenance:  Wipe the basin dry with a soft cloth after each use. Clean with a non-bleach mild soap. Do not use abrasive cleaners or harsh detergents, as these will compromise or remove the oxidized surface. Avoid the use of anti-bacterial soaps. Do not allow toothpaste or any kind of corrosive materials to sit on the surface of the sink. When water no longer forms beads on the surface of the basin, re-apply another coat of bees-wax containing carnauba. Expect the patina to change naturally over time. To get rid of spotting caused by hard water: Dilute white vinegar with an equal amount of water and fill sink or wipe on with a soft cloth. Allow to soak for several minutes and rinse thoroughly.