Alumni Profile • James Andela ex'77 and Cynthia Gelder Andela '80
Smashing misconceptions about glass

James and Cynthia AndelaJames Andela ex’77 describes himself as an out-of-the-box — sandbox, in this case — thinker. He and Cynthia Gelder Andela ’80 have pictures of their small children playing in a sandbox — of finely ground glass.

“Friendly glass” is the Andelas’ business, a business seeded 30 years ago in Calvin’s engineering department. As students of engineering professor Jim Bosscher, James and Cynthia worked on projects to design recycling equipment and systems. After leaving Calvin, they owned a tool-and-die manufacturing company in upstate New York for 10 years. Then, in 1991, while visiting Cynthia’s parents in Grand Rapids, the seed sprouted.

James read a newspaper article focusing on the fact that Bosscher’s students weren’t finding enough takers for their recycled glass. Then, as now, used glass is most often broken and re-melted to make new glass containers. James and Cynthia remembered a glass crusher some of their fellow engineering students had built in the mid-1970s. As they talked, James came up with an idea that, in his words, “took the Calvin bottle crusher a big step forward.” He sketched it, then went home to New York and built the first Andela Pulverizer.

The son of a mason, Andela knew the many uses for sand and gravel. The machine he designed could reduce glass — anything from bottles to broken windshields — to aggregate, ranging from the size of pebbles to fine powder. And none of it was sharp. Recycled glass coming out of the Andela Pulverizer was as good as sand — in some cases, better.

In the 15 years since he made that first machine, the Andelas’ business has become the manufacture of recycling equipment. Municipalities, national parks and private companies from Australia to England to Maui are recycling glass with the Andela Pulverizer and using the small, safe pieces to replace sand and gravel.

At Yellowstone National Park, pulverized glass is used as an underlay for walking trails. The city of Taos, N.M., adds the finest of the glass aggregate to wet paint to give reflectivity to pedestrian crosswalks; larger aggregate is used to filter and drain run-off.

The Andelas explain that the physical and chemical properties of glass make it more than a substitute for sand; in some applications, glass is better. Water percolates through glass nine times faster than it does through sand, for example, and glass particles trap contaminants that sand doesn’t. When fine glass is used in place of sand in sandblasting, the dust that results is not dangerous to breathe.

The uses for recycled glass keep multiplying. The biggest challenge, Cynthia said, is convincing people of what can be done with glass. That’s when the Andelas are apt to pull out pictures of their kids playing in a sandbox of finely crushed glass. Or an article from the Miami Herald that details a pilot project for using recycled glass to replenish lost beachfront.

The Andelas have decided that to promote friendly glass, they need to do more than sell the equipment to make it. They’ve begun to pulverize glass themselves and to demonstrate, on site, its uses, especially as a landscaping medium in flowerbeds, fountains and swimming pools. As Cynthia said, “It’s a whole new industry we’re creating here, step-by-step.”

To learn more about Andela recycled glass, go to