Metal Casting Zone Info Blog

Archive for December, 2009

It is not too farfetched to predict that in the future a complete building will be built from a computer. Similar technology has already begun to be used by the industrial design and manufacturing industries. One of the best-known and oldest technologies is called Stereo Lithography, because it involves a laser beam moving through a vat of ultraviolet-sensitive liquid polymer, which follows the contour of a digital 3D model. The beam strikes on a layer of ultraviolet-sensitive liquid polymer, and then the thin layer is solidified. The laser will keep repeating the same process from the bottom to the top of the 3D model. A temporary framing support for the model is required, because the process is from the bottom up. Stereo Lithography machines are manufactured by 3D Systems Inc., and they are also known as Stereo Lithography Apparatuses (SLA). The final model usually requires a little bit of sanding, and it is inappropriate for an office setting because this process produces toxic fumes. The following is a list of processes that may assist the automation of the building industry. These existing technologies can immediately assist the building industry; however they do require some modification to suit individual building types. It should be noted that these manufacturing processes are crucial to the development of building automation. Computers can produce precise results, while manual labor is imprecise. The direct digital manufacturing process can reduce errors and make digital building components affordable. The original prototype is always costly, but the cost can be reduced to a bare minimum by using rapid prototyping processes.

Rapid prototyping (RP) is a digital modeling process, which is a real physical model of a component (in prototype form) that is entirely created directly from a 3D CAD drawing. RP systems generate quick prototypes by constructing an additive and layer-by-layer process that is driven by 3D CAD data. RP is also known as desktop manufacturing or free-form fabrication. RP machines require STL data files, which are generated by the CAD system. An STL file is a data file format designed specifically for rapid prototyping machines. Any rapid prototyping system can use the STL file from any type of 3D CAD system that outputs the STL data. RP machines operate quite differently than typical CNC machines. RP machines are subtractive in nature, because they join together liquid, powder and sheet materials to form complex forms. Using layer-by-layer technology, RP systems fabricate plastic, wood, ceramic or metal objects based on several cross-sections from a 3D CAD model.

RP cannot be mistaken by rapid manufacturing (RM) or rapid tooling (RT); however, all the above mentioned processes involve 3D CAD files. RM is a rapid manufacturing process. RM is an ultimate process that manufactures parts directly from a computer. The benefits of any rapid processes are that fewer steps are required to achieve the final result and that

The original prototype is always costly, but the cost can be reduced they are much faster than the traditional methods. According to Wohlers, some companies are beginning to use rapid prototyping technologies to manufacture finished parts. Most of these applications are geared to small quantities of parts, because there are still some technical difficulties for RM in reaching the production capacity of injection molding, die-casting, or sheet metal stamping at the time of this publication. These technical difficulties are: inferior surface finishes to production molded parts; inadequate dimensional accuracy and repeatability; durability and cooling efficiency; small limited part sizes; and the time and expense associated with removing excess resin and performing post curing operations. “These applications are proving that rapid prototyping can be suitable for production in terms of speed, material properties, accuracy, and surface finish. Moreover, rapid prototyping of mechanical CAD designs is well established and will continue to grow. Soon many other applications will follow suit. Indeed, organizations will rely on the technology for sculpture, architecture, mold flow analysis, molecular modeling, forensic analysis for solving crimes, and a variety of uses yet to be conceived.”1

RAPID PROTOTYPING
Stereo Lithography Apparatus (SLA) – This is the oldest (discovered in the late 1980s) and most common technology. It involves a laser beam moving through a vat of ultraviolet-sensitive liquid polymer which follows the contour of the digital 3D model. The beam strikes on a layer of ultraviolet-sensitive liquid polymer, and then the thin layer is solidified. The laser will keep repeating the same process from the bottom to the top of the 3D model. A temporary framing support for the model is required, because the process is from the bottom up. Stereo Lithography machines are manufactured by 3D Systems Inc. The final model usually requires a little bit of sanding, and it is inappropriate for an office setting because this process produces toxic fumes. SLA is simple, fast and accurate.

Idea Applications

* Prototype or Presentation Model a quick, fast, and concise process for conveying the design intent. SLA is inappropriate for creating the final form, because the end result is highly fragile.
Object 3D printing – this process uses ink-jet technology with photo polymer resins. The ink-jet like head drops fine deposits of resin while a UV lamp cures these droplets immediately. Object 3D printing is also a layer-by-layer process. Objects created by 3D printers are highly detailed and accurate. No sanding is required, because the object is cleaned with a low-pressure water jet in the process.

* Appropriate for architectural model

* Form and fit analysis

* Concept and presentation models

* Sales and marketing samples

* Tooling patterns

Z Corporation’s 3D printer – The Z Corporation’s 3D printer works by creating physical 3D models directly from digital data, layer by layer. A part can be printed at the rate of 25mm (1″) vertical per hour. It is fast, versatile and simple comparing to other similar systems, allowing architects/engineers to produce a range of concept models and functional test parts quickly and inexpensively. The system is ideal for an office environment or educational institution, providing product developer’s easy access to a 3D Printer. “A 3D CAD file is imported into the proprietary system software. The software slices the file into thin cross sectional slices, which are fed to the 3D Printer. The 3D Printer creates the model one layer at a time by spreading a layer of powder and ink-jet printing a binder in the cross-section of the part. The process is repeated until every layer is printed and the part is complete and ready to be removed.”2

Idea Applications

* Ideal for conceptual models, architecture models, and functional testing prototypes

* Require Z-bond solution to make the component stronger.

* Can be used to make strong, high-definition parts and is the material of choice for printing color parts.

* Can be used to quickly fabricate parts that can be dipped in wax to produce investment casting patterns.

* Can be used to create sand casting molds for non-ferrous metals.

* Has been optimized for infiltration with Z-Snap epoxy to create
parts with plastic-like

When the search for a rapid tooling solution begins, it is common to use traditional tooling techniques as the benchmark. The goal becomes the replication of all the quality of a cut tool while slashing the delivery time and expense. With these standards, the options become limited. These imposed limitations can make it best to seek out a tool shop that is extremely fast and efficient at building cut tools in aluminum or steel. In the evaluation of projects, Accelerated Technologies often finds that a machined tool is a far superior solution.
Under the original, narrow definition, rapid tooling has limitations in many areas. These include:

* Tool life

* Accuracy

* Surface finish

* Resin selection

* Tool configuration

* Cycle time

* Part size

Each available rapid tooling solution presents limitations in at least two of these areas. When the strengths and weaknesses of the processes are presented, many elect to use traditional methods that may require more time. It certainly will be a dream comes true if technology brings down cost of buildings. Shopping for a designer house will be one of the choices open to everyone, not the privilege of a few. A 10 to 15 year recycling time for a house will be appropriate, because the recycling cost will be lower than the renovation cost.

Fast prototyping cannot replace our current building practice, but at least it will help to construct a mock-up to improve the design. It is a known fact that a full-size building mock-up is necessary to eliminate errors and the need for future design modifications. Fast prototyping can accelerate the mock-up process, bring down the cost, and speed up the final construction time.

Full-size building component prototypes are not yet in production, because they require detailed connections and some modifications. It is not hard to imagine, that in the near future an entire house will be manufactured by an LOM machine or other RP processes directly. Such a notion is exciting and will revolutionize the building industry. Rapid tooling is a powerful process that can definitely make the building process faster, cheaper, and better.  If you find this article interesting, and want to find out more about how emerging technologies change the field of architecture.  Please go to Amazon.com or barnsandnoble.com to check out Mr. Chang’s new book- Making of Digital Forms: A Study in Emerging Technologies in Architecture.

Footnotes
1) Wohlers, Terry, Computer Graphics World, November, 2001

2) ZPrinter 310 Plus Brochure, www.zcorp.com, March, 2008

Before crafting handmade jewellery two things, casting and making of jewellery by hand, must be understood. This will help you to decide whether making of jewellery by hand is worse or better, than casting.

The handcrafted jewellery is designed by hammering, bending, twisting and soldering the metal in desired form. For instance, while making a plain gold wedding ring the jeweller will start off by having a lump of gold metal in an undefined shape and will melt it down. Then he will pour the melted gold into a steel container which will harden the liquid for giving desired shape. The liquid will be turned into a thick bar. Then jeweller will roll the piece up to a time that he will finally get a long flat piece. After that he will cut down the pieces in a length that can be easily fit in customer’s finger. In the next stage he will hammer the piece to give a shape of ring and will join the both corners to create a ring. After that, he will give it a nice circular shape and polish it. Then recommended gems or crystals will be fitted into the ring. Now the gold wedding handmade ring is ready. This whole process might take one hour or little more. The whole process will start again as mentioned, if another ring is required to be made.

So the hand made jewellery piece will take hours or may be days to craft while casting it will take minutes for casting numerous identical pieces. In hand made jewellery the labor cost is a main factor. On casting, only the cleaning is required and nothing else and short time is spent in casting method.

For casting, in the jewellery trade the Lost Wax casting method is used as main method of casting. In this method, a master piece is prepared first and this master piece can be used to make unlimited copies of the jewellery item. In casting method large number of rings are made at one time but in hand made method only one piece is made at one time. So it can be said that the piece of handmade jewellery is stronger and heavier because of the techniques used like hammering and filling which make the piece hard and qualitative.

In casting sometimes the bubbles remains inside and missed by the manufacturer, which make it a less quality product and less durable. Nowadays this kind of problem can be easily controlled by highly sophisticated equipments but it could happen. The casting method can also be said a duplicating method by which a manufacturer copies number of rings of a piece.

So comparing both methods, the hand made piece of jewellery can be a unique thing and an expensive one. Casting method is cheaper and many people can enjoy the same product. Handmade jewellery is long lasting, durable and harder as compared to jewellery made with the casting method.

With sand casting the mold is broken up after each casting operation, but with the process known as gravity die casting, the mold also called a ‘die’ is manufactured from metal, and can be utilised a giant number of times. This suggests that the die is far more costly to make, than an expendable ‘one use only’ mold. An intermediate technique gets use from semipermanent molds, which are made of gypsum plaster or fireclay, which may be employed continually for a controlled number of castings. With gravity die casting, the most widely used materials for die-making are cast iron, steel, and heat resisting alloys of iron. For some specific purposes other materials are used to manufacture the dies, and these can include, aluminum. Copper or graphite. A metal die can produce smooth castings with a clean surface, and a very high dimensional accuracy. These castings require awfully little last machining or other finishing treatment. The service life of metal dies can vary in terms of the amount of castings it can produce, and this relies on certain considerations such as the casting material, the thermal metal shock resistance of the die material, the temperature at which it is poured, and the casting technique employed.

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Many different details need to be considered when designing the pattern from that the die is made. For example the pouring-gate system and risers have to be considered so that the walls of mold permit a quenching action upon the molten metal so it van harden more rapidly than in sand casting. Also the die must be supplied with channels at the joints and air vent holes to allow air from the hot metal to escape from the interior of the die. The die must also be built so it won’t restrict the shrinkage that occurs, when the metal cools. Shrinkage can present difficulties when designing the cores which form the casting. Usually the cores are made of steel or special alloys, and sometimes compressible sand or shell cores are used.

To prevent the casting metal from sticking to the die, the die can be given an internal coating of chalk, clay, or bone ash with water glass as a binder. This mixture can be applied to the die by spraying, brushing or immersion.

With straightforward castings the molten metal may be poured in at the top. It should be designed to allow the molten metal to flow quickly without turbulence into all elements of the die. For metals with low melting points the die is frequently heated to stop premature solidification, and for metals with a high melting point, the die may be artificially cooled after each casting operation.

Slowly moving or angling the die while casting can reduce turbulence and enable the metal to flow more smoothly, especially when heavy castings are being produced. For awkwardly formed castings, a vacuum may be applied to help the filling of the die. Slush casting, is a technique used for producing decorative or hollow castings : the molten metal is poured into the die, and when a solid shell of acceptable thickness has formed, the remaining liquid is poured out.

Although die castings are less expensive than sand castings, the die tooling is dearer, and a perfect number of castings have to be produced to make the process cheap.

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Beautiful handcrafted designer jewelry is always in high demand. This is because handmade items are delicate and exceptional. And when the articles are made by following your own specifications, they are even more beautiful and alluring. Many designers all over the world offer personalized and custom-designed jewelry to their customers. You can also find websites where you can choose your own stones, metal setting and overall design of the article you are looking for. By following this method you can create your own jewelry articles by using certified diamonds and precious gemstones. In this article we will explore some of the most popular custom-designed jewelry articles.

High quality handmade jewelry is offered by only a few renowned designers. You can search for websites where personalized jewelry option is available. Some designers also offer to use stones and metals provided by you. If you do not trust the selection of different jewelry makers, you can provide them with your own precious gemstones and diamond collection to be used on jewelry articles. Custom engagement rings can also be created in a similar manner by specifying your diamond cut, clarity, color and carat. This way affordable and totally unique rings and personalized wedding bands can be bought.

Engraved designer jewelry in the handmade category is also loved by many people across the globe. The designers show the casting and cut of custom-designed jewelry before finishing it and giving it final touches. The finished pieces are quite stunning and absolutely beautiful. You can design rings, earrings, necklaces and bracelets for both men and women. Rare designs like interlocking, tri-color and rolling rings can also be created by using the custom-design jewelry option. People order nugget rings, hand engraved wedding bands and gemstone rings in this category. In addition to these, lucky or four-leaf clover pendants, sacred heart necklaces, diamond earrings and gemstone bracelets can also be ordered.

People like to buy custom-made designer jewelry because of the wide range of exotic colored crystals and precious gemstones that can be used. These gemstones include, but are not limited to, aquamarine, garnet, sapphire, peridot, diamond, amethyst, ruby, opal, and emerald. In addition to these, you can also select among different Swarovski crystals such as bicones, briolettes, and rhinestones, and glass beads including heart-shaped silver beads, and millefiori beads in different shapes and colors. By utilizing these inexpensive crystals and semi-precious gemstones you can specify and create a fairly affordable jewelry article for yourself.

There are many categories of handmade designer jewelry and one of these is the custom-designed category. There are many websites where personalized jewelry is offered. By using this option one can specify their own choice of gemstones and metal setting to create a piece according to their requirements and budget. Diamond engagement rings and wedding bands can also be made by following this method. Religious jewelry, lucky necklaces, leather and magnetic bracelets, and modern silver and gold chains can be custom-designed to suit your specifications. You can find a number of design ideas and instructions on how to create your own jewelry online.

Whenever we think of trendy jewelry, sterling silver accessories come to mind. Sterling silver jewelry is the latest offering by jewelry designers to the new generation. Gold still continues to cast its charm; but sterling silver has particularly made its way to the hearts of the new age men and women. All silver jewelry is not sterling; according to the federal law, sterling silver must be at least 92.5% silver and 7.5% of other metals/alloy like copper or platinum.

Like any other jewelry piece, sterling silver jewelry too needs to be well looked after to ensure long lasting luster. A simple way to clean Ster. Silver jewelry is by using baking soda. Just follow the instructions given below:

i. Boil the required amount of water so as to submerge all the sterling silver pieces.

ii. Line a glass or plastic dish with an aluminum foil. You can also use an aluminum pan in case you are not going to use it for cooking purpose in future.

iii. Place the jewelry items on the pan and ensure that the silver is in contact with aluminum.

iv. Sprinkle baking soda on the jewelry, just forming a thin layer.

v. Pour adequate water so as to just immerse the jewelry. Notice how bubbles are formed giving off a rotten-egg odor.

vi. Stir the jewelry pieces lightly with a wood or plastic stick to notice that the silver jewelry has regained its luster.

vii. Rinse your jewelry. Put a sieve over the drain to avoid losing small items like pendants or earrings.

viii. Use an absorbent towel to wipe the pieces gently.

ix. Polish with a soft cloth to give the final touch.

Since sterling silver tarnishes on coming into contact with moisture, it needs to be wiped dry before finally sealing it in air-tight containers. A chemical solution called tarnish dip is often used to remove heavy tarnish. Silver polish, too, can be used but it is not generally able to clean grooves and crevices.

If you find the entire process of jewelry cleaning too wearisome, you can give it to a trusted jewelry store for cleaning. Just make sure you assess the item before taking it home. Sterling silver jewelry carries two quality marks- sterling, ster., 925 or .925, while the other mark refers to the initials of the maker or a registered trademark.

You can also try out another home-check. Scratch an inconspicuous spot on the jewelry. Put a little drop of nitric acid. If the area turns grey, then it is sterling silver.

Collecting diecast vehicles consists of acquiring specific items based on your particular interests, such as airplanes, cars, trains, ship models, etc. Although some people just accumulate them, this is a passionate hobby for most folks, in which the genuine collector organizes carefully those items to catalog them and proudly display them. The depth and breadth of every collection is as unique as every collector is, and they are the ones that determine if a collection will focus on a specific subtopic within their area of general interests or if they only want to accumulate determined items. As an example, a collector may collect diecast vehicles trying to accumulate any or all of them, while another individual could prefer collecting only a model, brand or marquee.

Diecast vehicles and toys are an example of a collection that is never-ending. When you start collecting these vehicles it is like traveling back in time until the early decades of the 20th century when manufacturers such as Tootsie Toys in the United States, or Dinky Toys in the United Kingdom first produced the first diecast toys. Because the term “diecast” refers to any product produced using the casting method, the first models on the market were small cars or vans without plastic windows.

Over time, the vehicles were made of plastic and metal, more commonly an alloy of zinc and aluminum, including not only cars but also scale models of airplanes and trains, although automobiles are still the favorites among all of them. With more than 50 popular brands including Altaya, Bandai, Brooklin, CMC, Dragon Wings, Exoto, Guisval, Ixo, Jada, Johnny Ligntning, Kyosho, Lledo, Matchbox, Minichamps, Norev, Plasticos Argentinos, Racing Champions, RCCA, Revell, Tekno, Tomica, UT Models, Vitesse, and the popular Hot Wheels introduced by Mattel, among others.

Like with other popular collecting fields, diecast collecting has specialized commercial dealers that trade vehicles and related accessories. In fact, many individuals start collecting cars as a hobby to become dealers at a later date, either turning this hobby into a profession, or as a means to get extremely rare vehicles for their own collections, while they help other collectors in their pursuit of showcase-model cars. In the United Kingdom, there are teams specialized in visiting small and larger toy fairs to acquire incredible cars, in good conditions from Dinky Toys and Corgi, the main British collectibles companies. Dinky Toys was first introduced in early 1934 by Meccano Ltd of Liverpool, England, presenting a new line of modeled miniatures, as diecast vehicles were first known.

Corgi Toys began producing scale model cars until July 1956 under the supervision of Mettoy Playcraft Ltd. in Swansea, Wales, along with Dinky Toys, and the American Tootsie Toys, which is one of the most wanted brands of collectors worldwide. However, there are many other popular manufacturers from the United States, Japan, Germany, France, Italy, Spain, etc.

Rarely a diecast collector completes a collection because new models of cars are always available, and collecting never stops, you can always expand or start an entirely new collection in a subtopic, such as cars, then sport cars, vans, etc. From Hot Wheels to Matchbox and from Bandai to Tomica, including all the other brands, diecasts models include popular automobile marques. Packard, MG, Morris, Hillman, Austin, Alfa Romeo, Bentley, Citroen, Opel, Triumph, Talbot, Gwynne, Vauxhall, Reliant, Singer, Bristol, Wolseley, Innocenti, Healey, Siddeley, BSA, Darracq, Crossley, Jowett, Frazer Nash, Northern, Renault, Ford, Chrysler, and the classics Jaguar, Mercedes Benz and Rolls Royce, just to name a few.

Broadening a collection is not that hard, even when focusing on a single marquee, because there are different models from the twenties, thirties, forties, fifties, sixties, seventies, etc. Hence, every diecast Collector has a world of possibilities when gathering diecast models from almost any period of time as early as models from 1885, when the first automobile driven by internal combustion was introduced by German inventor Karl Friedrich Benz, to actual models in modern car showcases.

Diecast vehicles come in various scales, the most popular ranging from 1:28 to 1:64 scale, although many collectors prefer focusing their collections on the 1:43 and 1:50 scales. Diecast toys were originally designed for children, but the collecting boom started during the 1950′s when grown children stated to keep their cars instead of throwing them away and adults discovered them as valuable collectible items.

There is computer software that is made just for collecting diecast vehicles. Anyone who has a small or large diecast vehicle collection can easily keep track of what vehicle they have, the color, condition, cost, value, scale and lots of other info for each record (vehicle). This is the most easiest to use software of it’s kind, and it is made 100% for diecast collecting. The software is described in detail and you can download a free demo version of it at this website address:

http://www.rb59.com/diecast

By Robert W. Benjamin

Copyright © 2006

You may publish this article in your ezine, newsletter or on your website as long as it is reprinted in its entirety and without modification except for formatting needs or grammar corrections.

What is behind the subject or business termed as centrifugal casting? Surf along and know more about the steps behind the system and the applications it offers. All these are seen in this piece of writing.

Centrifugal casting – also popular as rotocasting – is popular to industries and artists. Behind it are some stages to achieve a specific shape; all are treated through the help of devices where the mold is placed and directed. Objects utilized in this undertaking are glass, stainless steel, iron and several alloys such as nickel, copper and aluminum.

Centrifugal casting procedures

When speaking of centrifugal casting procedures, one must take note of the industry where they are wanted. The most general ones include:

All sorts of little parts including jewelry.. The articulated arm spinning process for casting is utilized for these businesses. The axle in the procedure operate with the presence of any of these two components – a spring or a driver. Completing the procedure are other pieces such as the tub where hot metals are protected.

Industrial directing. This includes pouring warm metal in a disk-shaped cast. The method is normally done with liquefied metal poured into its core.

Constructing of telescope mirrors.. The minor cast as well as the back pattern are charged through the glass materials and are heated until such time that the glass transforms to liquid. This method generally takes a month or even more than that just for cooling targets.

Uses for centrifugal casting

The varying applications of centrifugal casting expand to:

Molding of glass items into sphere-shaped items.

Formation of railway carriage wheels and equipment fittings as well as other cylindrical-shaped items.

Shaping of important objects including pressure vessels, boilers, cylinder liners, flywheels and pipes.

Forming the cast for centrifugal casting is made possible through the presence of an arm that turns on the region where mold forming is needed. Exertion of centrifugal force and the presence of containers are also important for any project completion.

If you talk about trends that are never stale then donning antique jewelry is one of them. As antique jewelry is very valuable and exquisite, it is highly regarded and its possession is vastly cherished. It is the wish and desire of every woman to own some of the antique jewelry pieces as they make woman look more appealing and attractive than ever and adds up to the overall persona immediately. Things are even better if it is Egyptian jewelry as it is exotic and embedded with precious stones all over. The patterns and the designs of the Egyptian jewelry are so inviting and fascinating that they become instantly irresistible and attractive for the wearer who becomes the star of the crowd once they have worn it.

Egyptian jewelry basically is composed by various conventional and eccentric, or says out of the league articles, including beautiful pendants, statues and cartouches. Cartouches are the pendants that bear the name of the kings whom they belonged to encircled in special designs. The designs of the Egyptian jewelry appear different as they symbolize various concepts like happiness, life, evolution, eternity, recreation and resurrection. These days, these cartouches and pendants have become a great style statement that is simply unbeatable and really charming. Many people also don these jewelry pieces with a notion to cast off the evil eye and consider these pedants and cartouches as very lucky for them.

Egyptian antique jewelry can also be found having well crafted and exquisite statues that are used as pendants for chains and necklaces. The statues are usually of the famous gods in silver and gold and are really cherished a lot as they are carefully crafted and embedded with rare stones. These beautiful items of Egyptian jewelry require ample care as they are very valuable pieces of art. If you are interested in buying some great pieces of ancient era for yourself then you can procure them easily from any good antique jewelry shop or online jewelry stores for ancient items. Just make sure that you do not buy the imitation jewelry and get your money’s worth. These days a lot of online shops for ancient jewelry also offer with great discounts making these vintage items all the more affordable. So, do not keep waiting, get a pretty vintage piece now and be the star among the entire crowd.

Jewelers who specialize in custom designing often use the lost wax casting method to create one-of-a-kind rings, charms, pendants, or other specialized items out of precious metals.

First the jeweler may sketch an idea on paper, especially if he or she is working with a client.  When the diagrammed sketch is approved, the jeweler then fashions an exact replica of the finished item in a soft, pliable wax.  The wax pattern, or maquette, is fitted with a stem called a sprue, which will create an exit for the wax when it is burned out.

This wax form is weighed to determine the amount of metal that will be needed.  It is then attached to a base and fitted with a tumbler that holds the mold material, which is plaster mixed with water to a cake batter consistency, called investment.  It must be free of bubbles before pouring into the tumbler, so it is placed in a vacuum to remove all the air.  The investment is poured into the tumbler and then taken to a kiln to have the wax burned out.

A jeweler’s centrifuge machine is the tool that injects the liquid metal into the mold.  The mold is taken from the kiln and placed in a holder that has a hollow arm attached to a cup that lines up with the hole in the mold. The pre-measured metal is placed in this small crucible, and then heated with a torch until it is liquid. 

The pin is then released on the centrifuge, and it spins rapidly around while the liquid metal is forced into the tumbler and mold. Once the spinning stops, the tumbler is removed from the centrifuge with tongs (it is extremely hot), dipped into cold water, and the plaster cracks and falls off of the metal inside.

At this point, the beautifully designed object created on paper does not even slightly resemble the blob of metal in the jeweler’s tongs.  This is because the base (or button) and the sprue are now metal like the rest of the design, and must be sawed and ground off with a jewelers’ Dremel tool, which is an instrument much like a dentist’s drill.

Much fine sanding and shaping is done with the Dremel and its attachments, and gradually the original design emerges.  Jewelers’ rouge puts a nice patina on the finish, and after much polishing, the piece is now ready for use.

Having a custom-made, jeweler-designed ring, pendant, charm, or other special item is something to be proud of, since it can define who you are, what your interests are, or what is important your life.