The Process of Creating a Bronze Sculpture

"happy dance"
is a recently completed, commissioned piece.
It measures 65cm, (39 inches) at the highest point.
It is cast bronze, the original was clay.

The following are some photos that show the creation of "happy dance".
Which was started in June of 2002 and finished in October of 2003.

First, Paula was contacted by the family who was interested in having
a sculpture made for them. Together they discussed the ideas for the piece.
They were looking for it to represent their two lively children,
and being familiar with Zima's work, were not looking for a realistic
rendition. They sent photos of the kids, along with descriptions of their ways
of being. From this information, Paula came up with several sketches for
them to choose from. They picked the one they all liked the best,
and with a few suggestions, we got started.


These next two photos show the maquette, which measures
about 12 cm, or 5 inches, tall. Paula doesn't always make a maquette,
but it sometimes helps. The family lives out of state,
so photographs were sent for them to see.



These photos (below) show the steel armature, which was necessary
in order to support the weight of the clay, which will be 150 #'s or more.
The clay is being slapped onto the armature,
It is important to get it on there good and firm, so that it won't slump down.



Here the clay is beginning to show the form, and the next photo shows it
almost complete. At first the work always seems to go quickly,
it may of taken only a day or two to reach the first stage.Then, the work slows down,
as the smaller detail is considered. It could take weeks to get it to the final stage.
Sometimes a piece has to just wait, carefully wrapped in plastic to keep the clay moist,
until the time is right, to know what the next step to take is.




'happy dance" from the side, and then a close up of the faces.



When the clay work was finally finished, photos were taken
so tht the family could see it and make sure that they were happy with
how it has turned out. The next step is to start to prepare the mold.
We do some of the mold making right in the sculpture studio.
First a thin metal dam is built along the parting line. then the first
layer of mold rubber is put on. ( It is layered on several times until
it reaches just the right thickness.)



This shows a bit of the final thick mold, which in this case is a bright yellow,
with a plaster "mother mold" on top of it, for strengthening the rubber mold.
The mother mold is applied before the mold rubber is removed from the original clay sculpture.
The next photo shows the rubber mold for the back half of the sculpture,
lying on the table, supported by the mother mold.




The next step is to brush a layer of wax into the mold, about 5mm, or 3/16 ", thick.
After the wax cools, it is removed from the molds, and all parts are seamed together,
so that now you have a hollow, 5mm thick, wax replica of the original sculpture.
This has to be worked to remove any imperfections that may of occured in the process.
The next photo shows the "cleaned-up" wax at the foundry. you can see that it is not
completely put together. It will get cut apart even farther, depending on how the foundry
see's fit,in order to cast it correctly.



Here you see the wax sprues, that are used to hold the wax sculpture in position.
The arms have been removed and will be cast separately, as will the legs, and base
and the one leg that was kicking out by itself. The next photo shows the main part of the
sculpture with the wax sprues that will become the channels and vents for the bronze
to be poured down, and the air to excape from.


This shows the arms being dipped into the slurry, carefully, to be sure that it is completely
covered inside and out. Next, while the slurry is still wet, it is coated with a silicon sand.
This will then be put up on a shelf to dry. The process will happen usually two more times,
until a strong, thick shell is built up.



Here you see the main part of the sculpture, with it's finished shell, which is a bright
yellow at this point. The next step, after the shells are thoroughly dried, is to place
them in a large kiln, where the intense heat melts the wax, which flows down and out,
and is burned out of the shell. Because the shell is quite large, it has been wrapped
with wire for extra support to keep it from breaking. It is shown, now
white in color, in a sand filled metal container, waiting for the bronze.




These two photos show the furnace where the bronze bars are being melted,
soon to be poured into the waiting shell.



The bronze is being poured out of the crucible, in to the small shell of the arms.
The next, darker photo, shows the molten bronze being poured into the
larger shell of the main part of the sculpture.




Here you can see the bronze, just after it was poured into the shell. It will
have to cool for a while, to become solid, and then have the shell broken away.
After all of the parts have been cast, and cooled, and the shells broken off, the parts are
welded together. Now, you have a bronze casting of the original clay sculpture. The bronze is the
same thickness as was the red wax that was brushed into the rubber mold. The sculpture is hollow.



The next step is to carefully grind and polish away any imperfections caused
by the welding, and to rework the texture that was lost where the seams were made.
After the artist is happy with how it all looks, the patina is applied. In this case,
it is a simple outdoor patina, for a pre-aged look, instead of the pale look of
the raw bronze. A coat of automotive wax was applied to the sculpture
in order to protect the look of the patina.




Large stainless steel bolts were welded to the underside of the base for mounting.
The next step is to have a crate made, and ship "happy dance" to it's new home.





Back to the top of the page.

Paintings,Sculpture and all contents of this site
Copyright © 2002, 2003 Paula Zima.
All Rights Reserved