The rarest and finest of Jack’s sculptures are without equal in this World.  These masterpieces are brought forth into their one-of-a-kind existence through the medium of welded steel wire which is painstakingly laid down and added, wire upon wire and layer upon layer, by the hands of our Master Sculptor in creating a smaller than life image of nature’s wildlife.

The steel wire utilized by Jack in the creation of his first group of sculptures came in the form of an impromptu pile of discarded hay baling wire and a broad scattering of old bed springs.  The largest of Jack's welded-steel sculptures, entitled Reach of the Bald Eagle, required approximately 1000 weld points of approximately 500 short pieces of the baling wire to create each of the Eagle's large feathers.  It took Jack twelve weeks to create his spectacular work of art, about as long as it takes Mother Nature to create this magnificent bird.  According to information provided by the National Eagle Center in Wabasha, Minnesota, USA, incubation for Bald Eagles is about 35 days and Bald Eagles fledge at about 10-14 weeks.[1]

The following explanation of the process-of-creation-in-brief does not provide Jack the full justice he is due in his process, but it does help an observer gain a greater appreciation for the end result.  Briefly, the time-consuming process of slowly and deliberately creating these sculptures begins with Jack having a vision of his subject held in his mind, a flaming torch held in one hand and a thread or rod of steel wire held in the other hand.  Jack first forms a wire “stick figure” of his wildlife subject.  Around and upon that wire figure, Jack fleshes out and bulks up his wildlife work-in-progress by creating the details of a supporting skeletal frame.  Over that frame of skeletal steel, depending upon the wildlife being memorialized, Jack eventually stretches and fits to covering perfection in molten steel either a blanketing hide, furry coat, or feathers bringing to life a creation worthy of purchase and prominent display by single-piece buyers, collectors, and investors alike.  For more, see our Sculpture in Progress.

                                   Bronze Sculpture Process

The Artist invests a considerable amount of time to create each unique bronze sculpture in a Limited Edition series.  As one may imagine, it would certainly take less time and would be less labor intensive for one to create a bronze sculpture of two conjoined spheres than to create a bronze sculpture of an octopus grappling with a cuttlefish.  What we do to create bronze sculptures at Nature Sculpted™ cannot be described as mass producing or stamping out reproductions.  What we do to create bronze sculpture at Nature Sculpted™ is to individually and meticulously hand-work the creation of each unique sculpture within a Limited Edition series, from preparing the wax Molding of the original sculpture to applying the finishing patina and wax to the last bronze in the series.

To assist others in gaining or deepening an understanding of the skills necessary for, and the complexities involved in, creating a bronze sculpture through the ancient “Lost Wax” casting process, we have provided here a step-by-step explanation of the process as utilized by Nature Sculpted™ to create our works of art.

The oldest known examples resulting from this process are the objects discovered in the Cave of the Treasure (Nahal Mishmar) hoard in southern Israel, which belong to the Chalcolithic period (4500-3500 BC).  Conservative Carbon 14 estimates date the items to c. 3700 BC.[2]

Steps of the Process

STEP 1 - Artist's Original:  The Artist creates an original model, often called a pattern, by sculpting a wildlife form in solid wax or clay, or through welded steel.  Upon completion of the original sculpted pattern, the Artist adds to the top most part of it an inverted cone of wax.  Utilizing this sculpted pattern, the Artist will produce a Mold which will be reusable throughout creation of each bronze sculpture in the Limited Edition series.






STEP 2 - The Mold:  A Mold, comprised of at least two parts, is made to replicate in a hollow wax model the intricacies of the original sculpted pattern.  The mold is often made in several sections in the application stage in order to facilitate easier disassembly later in the modeling process.  Recalling the octopus and cuttlefish, it is occasionally necessary to divide the pattern itself into several separate sections and to make a mold for each section, which will later be combined after casting with other sections in order to capture the detail of one sculpture.  An inner part or “Mother Mold” is made by applying multiple layers of liquid silicone directly upon the pattern and all but the top of its inverted cone.  To support the joining sections of this flexible silicone negative, a thick outer casing is made by generous application of Plaster of Paris to the outer surfaces of the silicone Mother Mold.  When the outer part of the mold is dry, the mold is opened in order to remove the pattern with its inverted cone, leaving an intricately detailed and flexible negative of the original sculpture, with a hole shaped like a funnel on top. 

STEP 3 - Hollow Wax Model:  Molten wax is poured into the empty mold, through the funnel shaped hole in the top of the mold, to fill the mold with wax.   The wax is briefly left to cool until a desired thickness of about 18 inch (3 mm) thick has set up on the inner surface of the mold.  Once the desired thickness is realized, the mold is turned upside down in order to pour out the extra molten wax.  The mold then contains, directly beneath the funnel, a hollow wax model which is an exact duplicate of the pattern or an exact likeness of a divided part of the pattern, as the case may be.  Wax examples are shown below.[3]







STEP 4 - Chasing Wax: The wax model is carefully removed from the mold and inspected, and any flaws, such as the join lines left by the silicone mold, are painstakingly removed or "chased" (re-detailed by adding, removing, or smoothing wax) by hand, utilizing a block of wax and flame heated dental instruments. Wax pieces that were molded separately can now be heated and attached in their rightful positions.  It is at this step and two which follow that the uniqueness of each one of the sculptures in a series is realized.  Although the Artist takes appropriate care to ensure that the wax model accurately reflects the original artwork, each piece will slightly differ from the next due to chasing needed in similar places on successive models.

Note: As the College Arts Association explains: “In its own way each casting of the artist’s original is unique, and not only a duplicate reproduction.  Whether it is casting 1/200 or 200/200, art specialists believe that two bronze casts that are finished by hand cannot be exact duplicates of each other.”[4]

STEP 5 - Sprues and Gates:  To lessen the likelihood of air pockets restricting the flow of bronze into and throughout a mold, sprues and gates (wax rods of various diameter and length) are strategically attached at each of their ends to various positions on the wax model and its inverted cone.  The sprues and gates are meant to form hollow tubes once the wax is melted out, to channel molten bronze into, and air out of, the mold for the sculpture.  In the end, molten bronze will only flow where mineral properties, gravity and adequate sprue and gate venting permit it to flow.





STEP 6 - Slurry and Investment:  The wax model with its sprues and gates is invested within a second mold, a disposable rigid ceramic shell, formed by repeatedly dipping the wax model into a vat containing a liquid slurry and then coating it with dry crystalline silica (sand).  On the first coating, powdered crystalline silica is used.  As the layers build up over the wax model, the coarseness of the silica is increased.  This process takes several days as each coating must be permitted to cure (dry) before application of the next coat.  The process is repeated until a coating of at least one-half inch covers the wax model.  The bigger the piece, the thicker the shell must be in order to accommodate the weight of the upcoming molten bronze pour.  Smaller pieces can be placed within a ceramic or steel sleeve, after the first coating, and covered to the top of the inverted cone with investment.








STEP 7 - Burnout Lost Wax:  The Lost Wax process derives its name from this burnout step in which the second mold, this one of slurry and silica investment, is placed upside down within a kiln (ceramic or brick oven) where it is fired (heated and baked) at high temperature to melt away the wax model and to harden the shell of the mold.  It is typical in this step for the wax model to be completely burned up and lost, not merely melted to a puddle - thus “Lost Wax.”  The end result of this step is a hollow shell, a ceramic mold in intricately detailed negative of the original sculpted model with an array of hollow venting tubes.

STEP 8 - Pre-Cast:  While still hot from the kiln, the second mold is quickly placed right side up onto a bed of hot sand within a steel tub.  The mold is then buried up to its top, where the funnel is, in hot sand, which will provide reinforcing support and heat absorption during the casting process which immediately follows.

STEP 9 - Casting:  Molten bronze sitting within a crucible (large ceramic cup) heated to 2100 degrees Fahrenheit approximately 1149 degrees Celsius, is poured into the hot shell to fill.  During a good pour, molten bronze should be seen to rise to the top of the vents at the time the funnel is seen to fill to its top with molten bronze.  Once filled, the mold and its bronze sculpture are left for hours to cool down to the point of being safe for human handling.









STEP 10 - Break Out/Release:  After the shell and the bronze sculpture inside have cooled, hand-held hammers are utilized to break the shell off and away from the sculpture and its attached venting tubes.  Removing the shell leaves the unfinished bronze sculpture imprisoned within a cage of bronze rods which were produced as molten bronze filled up the tubes venting the pour.  Any remaining fragments of the ceramic investment shell clinging to the sculpture are removed by sandblasting.

STEP 11 - Metal-chasing and Polish:  Similar to chasing the wax model, the bronze sculpture is worked for a period of days with small metal saws and grinders as the surrounding cage of sprues and gates is removed and all attachment points are ground and filed down, to the surface of the sculpture, until all of the telltale signs of the casting process are removed.  If the bronze sculpture was cast in pieces, the pieces are then reassembled and welded together in their appropriate positions, with the welds being ground and filed down.  Any pits left on the surface of the sculpture by small air bubbles trapped during the casting process are filled in utilizing a welding torch and a bronze welding rod.    Similar to sandblasting, an extremely fine glass beading is blasted over the entire surface of the sculpture to ensure an even bronze finish.  At this point the sculpture looks like a metal image of the original wax model.  This is the second point at which each sculpture in a Limited Edition series may obtain its unique character, slightly differing from the next due to chasing needed in similar and different places on successive castings of the sculpture.

STEP 12 - Patina:  Our bronze sculptures present with traditional hand-applied patinas (brown coloration) which are the result of induced oxidation of the bronze surface utilizing the application of heat from a hand-held torch, acids applied by paint brush, and occasionally the application of other chemicals. The patina is further enhanced by applying over it a coating of semi-hard wax while the sculpture is still hot.  Once cooled, the surfaces of the bronze sculpture are buffed to a shine with a soft bristle brush and cotton towel.  This is the third point at which each sculpture in a Limited Edition series may obtain its unique character, with a patina differing ever so slightly one from another.

We hope that this explanation of the Lost Wax process as utilized by Nature Sculpted™ has assisted readers in gaining or deepening an understanding of the skills necessary for, and the complexities involved in, creating our unique bronze sculptures.

______________________________
1.  Open New Tab: http://www.nationaleaglecenter.org/eagle-nesting-young.
2. Department of Ancient Near Eastern Art. “The Nahal Mishmar Treasure.” In Heilbrunn Timeline of Art History. New York: The Metropolitan Museum of Art, 2000-.  Open New Tab: http://www.metmuseum.org.
3.  Original images courtesy Owen Weng,Tany Foundry, China.
4. The College Art Association, STATEMENT ON STANDARDS FOR THE PRODUCTION AND REPRODUCTION OF SCULPTURE, Adopted by the Board of Directors on February 17, 2013.  Open New Tab:  http://www.collegeart.org/guidelines/sculpture.

Bighorn Ram No. 2 - Black Wax Original
Bull Head Up - Main Body Emerald Wax and Sprues
Small Wax Model
Large Wax Model
Original sculpture model in solid Black Wax
Bighorn Ram hollow wax original model.
Bighorn Ram hollow wax original model.
Moose sculpture hollow wax original model.
Moose sculpture hollow wax original model.
Moose Sculpture hollow wax original model.
Prior to investment Bull Head Up main body Emerald wax and sprues for bronze sculpture casting
Large wax model encased in shell for burn-out and bronze sculpture casting.
Small wax model in casing with investment poured to top of wax cone.
Large red hot crucible pouring molten bronze into sculpture investment shell.
Bighorn Ram hollow wax original model.
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Bighorn with wax cone on top.
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