Artisan Brothers Update Work In Bronze
Foundry Also A Teaching Tool
Monday, June 18, 1990
By Robin Stanton
SULTAN—The magic of alchemy lives on in a steel building behind the Sultan park and ride lot.
There, Kevin and Todd Pettelle heat bronze to glowing white liquid and create works of art that can survive 10,000 years or more.
The brothers have worked for three years establishing a foundry, Northwest Artworks, to cast pieces for area sculptors.
The foundry is a family partnership, born out of Kevin Pettelle’s frustration in finding someone to cast his own sculptures and aided by an investment from their artist father, Ed Pettelle.
The brothers, complement each other, they say. Todd Pettelle has the business skills, while Kevin Pettelle is the artist and technician.
“Everything’s fallen into place for us,” Todd Pettelle said on a recent Saturday afternoon. “Whenever we've tried to push things along too fast, it hasn't worked out. But as we let things happen in their own time, everything falls into place.”
On this particular Saturday, the brothers were working on a special project. Three classes from Canyon Creek Elementary had made tiny sculptures under the guidance of volunteer art teacher Stacey Mayer. The Pettelles were preparing to cast the 70 pieces.
Mayer and her 8-year-old daughter, Shannon, who created one of the sculptures, came to watch the pour.
Out the back door, misty hills pucker out of the Skykomish River flatlands. It was gray and cold as the rain beat down, but inside a crucible of bronze glowed white and hot.
The brothers designed the shop with disaster in mind, Kevin Pettelle said, and have avoided it so far. The furnace and the tray that holds the molds sit on a mesh steel deck about 2 ½ feet above the cement floor. If any molten metal spills during a pour, it drips to a safe distance below.
Bronze is the oldest alloy known. Artisans first started working the blend of copper and tin about 3500 B.C. Those were the times when alchemists claimed to be able to turn base metals into gold and smelters were in secret places.
The bronze is heated to between 1,950 and 2,150 degrees Fahrenheit. The hotter the metal, the more fluid it is, which allows it to flow into the tiny crevices of the molds. Fifty degrees can make a difference, Kevin Petttelle said.
As the bronze melted, Todd Pettelle added scrapes from earlier projects. Dressed in leather protective clothing and wearing a helmet, he used tongs to place the scrapes atop the furnace first, to let them dry and heat. Adding cold bronze to the fiery pieces on the verge of melting could mean an explosion.
They've worked with other foundries, particularly Pratt Fine Arts Center in Seattle, to learn the skills, Kevin Pettelle said. But they've had to develop their won techniques for their operation.
You can follow someone else’s directions step by step, doing everything right, and nine times out of 10 it won’t work, Todd Pettelle said. Even the humidity will affect a pour.
As time for the pour approached, he probed the bronze with a long metal thermometer. The molds sat in sand in a metal tray in the center of the steel deck. They were preheated to about 1,600 degrees, which helps keep the bronze hot enough to capture detail work.
When the bronze reached the right temperature, the two brothers used long tongs to grasp either side of the 90-pound crucible. They lifted it out of the furnace and poured a stream of glowing white liquid into each mold. Working quickly, with few words, they topped each one, scraping the bottom of the barrel into bar-shaped molds on the side of the tray.
The molds themselves glowed pinkish orange. The brothers tossed the molds into a wheelbarrow and rolled them outside to cool. Kevin Pettelle blew a stream of cold air into the nooks and crannies of the mold, to ensure they cooled evenly. Raindrops hissed into steam as they hit the molds.
“Some times we roast hot dogs or marshmallows over them,: Kevin Pettelle told Mayer.
As they cooled, the molds began to crack. Within about 10 minutes, Kevin Pettelle hammered at a mold to uncover the sculptures within.
Out leaped a turtle, a snake, a space shuttle and a horse’s head.
As each group was uncovered, the Pettelles and the Mayers clustered round, examining each tiny figure. Shannon’s eyes glowed as she spotted her tiny snowman.
It was an almost perfect pour. Details of leaves and feathers, letters and lines were captured in bronze for many lifetimes.
A few days later, Mayer brought the sculptures back to the artists at Canyon Creek Elementary. She worked with Susan Kurokawa’s second-grad class, and Dennis Hamburg’s fifth/sixth-grade class. The children were excited and impatient to see their work
“I made this slug just to stick on my mom's glass,” said Matthew Oaks, a student in Stowe’s class.
But Mayer had a more lasting impression in mind.
“I want this to plant a seed in your brain, so you know that if you want to do something, you can,” she told the students. “Don’t lose these, don’t throw them away, but keep them to feed your dreams.
Making molds not quick process
SULTAN – Preparing a sculpture for casting into bronze can take anywhere from six weeks to three months, say Kevin and Todd Pettelle of Northwest Artworks.
From a wax or clay figure, the brothers make a reusable master mold that includes a flexible inner mold and a rigid outer mold to hold it steady.
A wax pattern is made from the master mold and attached to a central core along with special devices that direct the way the metal will enter and fill the molds.
A secondary ceramic mold is made round the wax patter. It is flashed-fired, plunged into a 1,700-degree Fahrenheit furnace for 20 minutes to one and a half hours.
This hardens the ceramic shell and burns out the wax. The ceramic molds are then ready to be filled with molten bronze.
For casting, large sculptures must be cut into smaller pieces that are later welded together. Body parts sit on storage shelves around the Northwest Artworks shop – rows of legs, rows of torsos with heads. The finished pieces show no seams where they've been welded.