I first started lost-wax casting in high school some time ago.  Since then life has taken me in many directions.  I came back to lost wax casting at Wowser, and since then my creative side has led me to add braising, welding, a 40 ton press, and an electric screw gun to my arsenal of skills for working metals in the creation of jewelry.   I am also about to learn how to create 3D pieces of fiber for casting.  There is always more to learn about something you love doing.

For this article I am going to take you through the process of lost wax casting.  As with any form of art, there are many ways to ‘get there’ and this is just one of them.

Lost-wax casting (also called investment casting) is the process by which a duplicate metal sculpture (often silver, gold, brass or bronze) is cast from an original sculpture.  The oldest known examples of this technique are Conservative Carbon 14 estimates, show items to c. 3700 BCE, making them more than 5700 years old!

The steps used in casting small sculptures today are fairly standardized. The process I am discussing today is waste wax process (or “waste mold casting”), because the mold is destroyed to remove the cast item, hence the name ‘lost wax’ as you lose your original wax mold through the process.   The process starts with making small wax sculptures using small tools (dental picks, files, and alcohol burners) to carve or add wax to the sculpture.  The finished wax sculpture is then attached to a stand and a metal ring surrounding the piece.  Care has to be taken to check the weight of the wax and calculate the weight that will be needed in metal to fill the mold, (there is a weight difference between wax and different metals).

Investment liquid is then made and poured over the wax, vacuumed to remove bubbles, and allowed to set up.  The base is then taken off, very carefully then fired in a very hot kiln for 5 to 11 hours which evaporates the original wax sculpture leaving a hollow the exact shape of your sculpture. The investment (mold) should be hot at the time of casting.  The metal ring and investment are placed in a centrifuge, with a crucible set in such a way molten metal can flow into the mold.  The chosen metal for the sculpture is weighed, added to the crucible and torched until it is the right temperature for casting, at which point the centrifuge is spun to send the molten metal into the investment model.

After the metal is cooled, the investment is peeled off, and the new metal sculpture is washed.  At this point the sprew, or stand, is cut away and polishing and grinding the metal piece begins.  I use a dremmel tool for most of this work.  The piece is then polished and finished.  A new work of art in metal is the final product, whether a ring, pendant, or pin and ready for use.

Wowser offers lost wax casting as a workshop.  You can sign up now and make your own custom design for your valentine. Call 459-9697 for details and then find us on Facebook.

– Cyndee Logan is one of the Founding members of Wowser and has been a community advocate in Willits for over 20 years.

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