John W. Kelly found his life's work while serving as an altar boy at St. Joseph Church in Bloomfield.

"I was mesmerized by the stained-glass windows," recalled Mr. Kelly, of Millvale. "I thought they were the most beautiful art I had ever seen."

Mr. Kelly, 64, has devoted much of the past three decades to refurbishing old windows and creating new works from pieces of colored, painted and kiln-fired glass.

His latest challenge is the restoration of three aisle windows from Sacred Heart Catholic Church in Shadyside. The imagery in the Gothic-style stained-glass windows includes nine medallions that illustrate scenes from the life of Jesus.

"I have been a glass man for 35 years, and these are the most complex windows I've ever worked on," Mr. Kelly said.

He estimated that each square foot of window contains 100 to 120 pieces of glass, held in place by lead connectors called "came."

Mr. Kelly owns Kelly Art Glass in Millvale. He was interviewed recently at his business, a former auto-body shop, where he and four artisans are restoring the windows.

He joined the Navy after graduating from Central Catholic High School in Oakland. His 10 years of duty included two tours of Vietnam.

While stationed on the West Coast, he took a course in stained-glass making in 1975 at the University of California at San Diego. He discovered he had a talent for the craft, and soon after, he set up a studio in his house.

After leaving the Navy and returning to Pennsylvania, he operated workshops in several locations in Allegheny and Butler counties. He has been in Millvale since 1999.

He relies on a regular crew of three full-timers, but that number has varied, depending on the number of projects he has under way.

The restoration of the Sacred Heart windows will take about 650 hours, Mr. Kelly said. The project is to be completed in time for Easter services.

"These windows are too important to the structure of the building and to the history of the parish to let them go into disrepair," the Rev. Robert Grecco said.

Father Grecco has been the pastor of Sacred Heart for the past four years. During that time Mr. Kelly and his crew have renovated three sets of aisle windows. This month they began work on the fourth.

The effort costs about $25,000 per set, and the work is being done as funds become available, Father Grecco said.

Restoration is a multistep, labor-intensive process.

The work began with the removal of the windows from their stone frames and their transportation to Mr. Kelly's workshop on a hilly, narrow street in Millvale.

He made a "cartoon" of each window -- a full-size black-and-white tracing that shows the dimensions of each piece of glass and of the lead "came" that holds them together.

Copies of the cartoons are used throughout the project to keep track of the order and condition of the window pieces. Using the cartoons as templates for the reassembled windows also assures that they will fit back into their unforgiving frames, Mr. Kelly said.

On a recent afternoon, Leslie Allen, of Ben Avon, was methodically removing bits of lead that held glass pieces in place. The lead had become badly corroded and pitted over the decades. The effects of seasonal heating and cooling and of exposure to the elements had reduced the strength of the material, and the windows had begun to bulge and buckle.

As Ms. Allen removed each piece of glass, she placed it on top of a copy of the cartoon. Each section of the windows will be reassembled in a large wooden container that crew members call a "pizza box." Each piece of glass is carefully examined.

"We'll decide if they should be repainted, recut, repaired or replaced," Mr. Kelly said.

The loose pieces are soaked overnight in a weak detergent solution in preparation for the next step.

David Fockler of the North Side and Linda Lang of Millvale used soft brushes and craft knives to clean the pieces, removing dirt and the remains of cement used to weatherproof the windows.

Pieces of glass that cannot be repaired are not discarded, Mr. Kelly said. They are returned, along with information about their origins, to the Catholic Diocese and stored in an archive.

Daneal Hansel of Burton, Ohio, was using very old techniques to "re-lead" the original, the repaired and the new pieces of glass. Starting in the lower left-hand corner of the window, she used 2-inch-long square-headed horseshoe nails to hold her work in place as she wrapped and cut the flexible lead "came" around each piece of glass.

The portion of window she was working on contained two story-telling medallions. The faces of the figures in each scene had been carefully painted, and each wore colorful clothing made of several pieces of bright glass. Elements ranged in size from as large as 2 inches by 4 inches to as small as a half-inch square.

She estimated that reassembly would take about four days.

Once the window has been put back together, each joint where pieces of lead come together will be soldered on both sides. Then workers will use a gray cement, made from linseed oil and calcium carbonate, to fill any gaps between the glass and the lead frame. It will make the window watertight.

As a final step, the crew will use cotton swabs to apply a chemical to the shiny new lead. The treatment will give its surface a dark patina that will match the other windows in the church.

Mr. Kelly did a survey of Sacred Heart's more than 5,000 square feet of stained glass. He estimated that restoring all the windows would take 20 years.

Church windows are much more than decoration, Father Grecco said.

"Centuries ago, all that people learned about their faith they learned from stained glass," he said. "They were the Bible for those who could not read."

Sacred Heart's windows were designed and created between the late 1920s and 1954 by artist George Sotter and his wife, Alice. They illustrate scenes from the life of Christ and from Catholic theology.

Kelly Art Glass is one of three or four Pittsburgh-area firms that do stained-glass restoration. Mr. Kelly estimated that there are about 6,000 churches within 50 miles of Pittsburgh, many of them built a century ago or earlier.

With 1,000 square feet of stained glass per church, that means there are about 6 million square feet of liturgical glass to be maintained in southwestern Pennsylvania, he said.

In addition to restoration projects, his company also creates original works for churches and private homes. Customers commission movable window-hangings to mark special family occasions, such as anniversaries, while others want portraits in glass of their beloved pets.

"Dogs, cats, frogs, turtles -- I've done them all," he said.

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