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Posts Tagged ‘wax’

Learn about using wax to make jewelry molds. Expert: Courtney Gray Contact: www.courtneygrayarts.com Bio: Courtney Gray is an artist and professional jewelry maker who creates jewelry from the design stage all the way through to the final product.

Hello,

Here we are on day three, ready to learn about Lost Wax Casting.

Lost Wax Casting is an ancient technique that has been used to
create very complicated metal castings and involved pieces that
would other wise be impossible either because of economic reasons
or manufacturing reasons. Everyone from small jewelers to large
industrial foundries can use Lost Wax Casting. This process is also
called Investment Casting when it is used in commercial industries.
While jewelry makers are the primary ones to use the Lost Wax Casting,
many others use it to achieve a number aims and goals.

Lost Wax Casting is the ideal and preferred method for artists who
are interested in making items like sculptures or rings from a
variety of alloys like bronze, steel, or copper. This process is q
uite involved but not all that complex as long as you have some kind
of metal casting know-how. For anyone wanting to experiment with
different casting methods Lost Wax Casting is a great option because
it involves a few materials and methods that are not normally
found in other methods like Sand Casting.

The most noticeable difference of Lost Wax Casting from other
castings is exactly what’s in the name; the wax. To use Lost Wax
Casting you do not necessarily have to be an artists but some skill
in sculpting might be nice. You are going to start off by creating
a sculpture from wax that will be the original.

You will then create a mold of the original. The mold is usually
created from plaster with latex lining to help preserve the details
of the original. If this is your first attempt at Lost Wax Casting
you may want to make an original without a lot of detail just to
get the feel for the entire process and so you do not become
discouraged if something does not work out. Remember metal casting
is a skill that must be learned by research, trial, and error.
Chances are that you will not be completely successful, the first
time around. The original piece is usually lost after the construction
of the mold. This is normal and if you do want to prevent this from
happening you can create the original from material other then wax
like a metal alloy.

When the mold is ready you are then going to pour molten wax,
you’re not ready for metal just yet, into the mold. The amount
of wax needed for this step depends on the desired thickness.
Once the copy is ready, you are going to remove it very carefully
from the mold. You will remove any of the impurities from the copy.
This is called chasing.

You will then sprue the copy. Spruing is the act of carefully
placing paths that will let the molten metal in and air out.
Afterwards, a ceramic shell is created around the copy. The shell
isn’t really ceramic but a combination of liquid silica and sand.
Traditionally, and in some areas still, animal dung and dirt is
used to create the shell. The choice of which shell material you
want to use is up to you. The shell is hardened in the kiln and
the wax melts out. If you want to reuse the wax then collect it
during this step. Wax can be reused a number of times and if you
are on a budget or are just trying out different designs and methods,
collecting the wax is encouraged. Once the wax is gone and all that
remains is the hollow shell you will want to run water through it
to make sure there are no leaks. If there are then you will need to
patch them before pouring the molten metal.

You are going to want to reheat the shell before pouring the metal
to avoid shattering the shell. The shell is still on the sprue tree
so pouring the metal is an easy process. When the metal has hardened,
then break the shell carefully and remove the cast. Afterwards, it
is up to you to finish the piece to your liking and preference.

The Lost Wax Casting process is an enjoyable experience but it does
use a few tools that you might need to purchase before hand, like
the wax and spruing tree. At the very least, you might want to try
Lost Wax Casting once or twice to get a feel for it. This way you
have another casting process at your disposal.

Here is a link to a Web Page that covers this E-Course Email:
http://www.metalcastingzone.com/lost-wax-casting/

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i have to make designs 15 designs for casting jewelry…5 soft, 5 hard wax, and 5 mix………i dont know what to draw for any of them…help?

What two benefits are they of using lost wax casting for jewelry manufacture?

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.

There are generally to ways to have your own piece of custom jewelry produced if you want to create one and the first way is to go to a jeweler that makes custom jewelry and have them produce it to your specifications. The other way to have it made is to create or sculpt it yourself in wax and then have a jeweler cast it in gold or silver for you.

This is basically the way that most all rings and bracelets are made, although there is finishing work that has to be done after it is cast, the basic form of the creation is determined in wax. Its called the “lost wax method” and it has been in use for thousands of years. Your idea is first created in wax by using sculpting or dental wax. Standard paraffin wax won’t do because it is too hard and stiff and bees wax is too soft.

The wax ring or bracelet is then given to the jeweler who then encases the wax sculpture in plaster. After the plaster that incases the wax ring or bracelet has cured and dried it is placed in a hot kiln so the wax piece inside of it can melt and burn out. What is removed from the kiln is a chunk of plaster that has the hollow shape of the ring or bracelet in it where the wax was.

Jewelers use a centrifugal caster that spins around as the molten gold or silver is forced in to the hollow place in the chunk of plaster by the centrifugal force. After the gold or silver inside of the chunk of plaster has been allowed to cool the plaster is chipped away to reveal the jewelry piece where the wax ring or bracelet once was.

Have you ever looked at a piece of your jewelry and wonderd just how the jeweler made it? How do they create the fine detail in a piece of jewelry and what about the smooth swirling shapes. The fact of the matter, is that every piece of fine jewelry starts out being made from wax. Its called the “lost wax” casting method and it is amazing to see from start top finish.

The first step is to create the piece out of sculpting wax, which is the same wax that dentists use to make crowns for peoples teeth with, because dentists use the lost wax method for casting gold crowns. Then the wax piece is then encased in a can that is filled with wet plaster and allowed to cure and dry. After the can of plaster with the wax piece in has dried it is then placed in a hot kiln so the wax “piece” in it can melt and burnout of it.

What is then removed from the kiln is a hunk of plaster with the hollow shape of the wax piece left in the middle of it. The jeweler will then place the hunk of plaster in a device that spins around and uses centrifugal force to push molten metal down into the hollow shape inside of the hunk of plaster. It will then be allowed to cool and then the plaster will be chipped away revealing the piece of jewelry where the wax piece once was.

It will be cleaned up and then any details will be carved into it or welded onto it using a jewelers delicate tools and a jewelers torch. If any stones or gems are to be added to it, that will be the last step that is taken. It is then given a final polish and it is done. This method of making jewelry has not changed in thousands of years.

Have you ever wondered as you looked at a piece of gold jewelry just how it it was made. How did the jeweler start out with raw bulk product and end up with the finished product. Jewelery is created using many methods but the most common method is by the “lost wax” casting method. It was developed in ancient times and it is still used to this day, although modern tools are now used.

The reason that is is called lost wax is, because the object that is to be created is first sculpted out of wax to the exact specifications that the finished product is going to look like. After the wax sculpture is completed it is then encased in a silica encasement or in the case of jewelery it is then encased in plaster. Then after the plaster encasement has hardened and dried it is put into an oven or kiln. This will cause the wax to melt and burn out leaving its hollow image inside of the plaster encasement.

Then the plaster encasement with the hollow shape of the piece of jewelry is placed into a casting centrifuge which is a device that will use centrifugal force to drive molten gold down through an opening in the chunk of plaster where it will fill the hollow spot left by the wax melting out. After it has cooled the plaster is broken open to reveal a piece of gold jewelry where the wax sculpture once was.

Its the same technique that is used to create larger bronze sculptures, only with bronze it is done on a larger scale and the centrifugal caster isn’t used. The lost wax casting method was what was used to bring civilization out of the Iron Age and into the Bronze Age. In ancient times primitive metal smiths would use bees wax to shape objects such as axes and arrow heads. These was objects were then encased in clay and placed in the bottom of fire pits to burn off.

If you are tossing around the idea of having a piece of custom jewelry created, there are a few things that you need to know first. One thing that you will want to know is that there are jewelers out there that will work with you but it will cost you if they have to do all of the design work.

The design work is first done in wax, because jewelry is cast using the “lost wax” casting method. This means that you will want to present your wax sculpture to the jeweler “ready to go” that is that all that has to be done is to encase it in plaster, set it up for a pour and then pour it.

A jeweler that is going to do the casting for you will gladly give you some sculpting wax to work with. You can’t use bees wax, because it is too soft and paraffin wax is too hard and brittle. Sculpting wax is the same wax that dentists also use and it comes in solid chunks and in sheets.

Working with wax takes time and practice and you will find it rather hard to work with. Pieces don’t stick together easily like clay, so you have to “work” two pieces of wax together carefully. Use fine dental type sculpting tools to work on your wax piece and handle it very carefully.

One thing that you will find is that the warmth of your fingers will cause your wax piece to bend out of shape when you handle it. The solution to this is to keep your piece in the refrigerator and periodically dip your hands in ice cold water when you are working on it. Make sure that nothing gets into the wax when you are working on it, because dirt won’t melt out and will end up being stuck in your piece of jewelry.

The design work is first done in wax, because jewelry is cast using the “lost wax” casting method. This means that you will want to present your wax sculpture to the jeweler “ready to go” that is that all that has to be done is to encase it in plaster, set it up for a pour and then pour it.

A jeweler that is going to do the casting for you will gladly give you some sculpting wax to work with. You can’t use bees wax, because it is too soft and paraffin wax is too hard and brittle. Sculpting wax is the same wax that dentists also use and it comes in solid chunks and in sheets.

Working with wax takes time and practice and you will find it rather hard to work with. Pieces don’t stick together easily like clay, so you have to “work” two pieces of wax together carefully. Use fine dental type sculpting tools to work on your wax piece and handle it very carefully.

One thing that you will find is that the warmth of your fingers will cause your wax piece to bend out of shape when you handle it. The solution to this is to keep your piece in the refrigerator and periodically dip your hands in ice cold water when you are working on it. Make sure that nothing gets into the wax when you are working on it, because dirt won’t melt out and will end up being stuck in your piece of jewelry.