CAMDEN, Maine — Years ago, then-18-year-old Peter Lindquist decided he was sick of the projects he had to do in shop class. He wanted to build something for his grandmother, but the typical trinkets were not going to do.

“In high school I built my grandmother a casket,” Lindquist, now 54, said Tuesday morning. “She already had bookcases and all the knickknacks you would make in shop class. I wasn’t going to make another damn table.”

His grandmother was 65, and a teenage Lindquist wrongly assumed she was close to death.

“I was determined to save her thousands of dollars,” he said.

So the teen invested $90 and made her a mahogany coffin for his school project. It took him the entire school year and he said he almost didn’t graduate because of it. But he finished his first casket by the end of his senior year and gave it to his grandmother, who used it 27 years later.

“She lived until she was 92,” he said. “It ended up being a family joke.”

So, one month ago, when Lindquist decided to start a coffin-building business, he knew it wouldn’t be such a mammoth task.

Lindquist, who works full time as a salesman for a Rockland company, hired a carpenter who builds no-frills pine boxes with rope handles. They cost $649, and he has sold three so far. He recommended filling the coffin with blankets or the like during living years and having it just in case.

“When the time comes, it is one less thing the family has to freak out about,” he said.

When creating his coffins, Lindquist works with eastern white pine from Searsmont’s Robbins Lumber, a company certified by the Sustainable Forestry Initiative. In this way, the product is sustainable.

“We live in Maine. We live near all these pine trees. Why not make these locally?” he said.

Lindquist’s wife, Sarah Ruef-Lindquist, also has ties with the death-planning industry. Ruef-Lindquist is a lawyer who works for Planning For Good, an organization that helps people leave gifts after they die, such as donations to nonprofits.

“It’s ironic she and I are both in the same business,” Lindquist said with a laugh.

Ruef-Lindquist called her husband “an extremely practical person” and said she doesn’t think her ties to the industry lured him in.

“I think he has had an interest in that area of carpentry, if you will, for a long time. I don’t think I had any influence in that,” she said.

There have been some problems with homemade caskets, but Lindquist said his are tested and are proved to hold corpses properly.

Ken Davenport, the assistant office manager at Belfast’s Crabiel-Riposta Funeral Home, said he has been aware of issues with some nonfuneral-home coffins.

Some, he said, had no handles. The boxes often didn’t have built-in mechanisms to lift the body up for viewing at a service, and sometimes self-made caskets have leaked because they weren’t made of moistureproof materials, Davenport said.

“The casket is not dimensionally the right size for someone to fit in — we ran into that ourselves,” Davenport said of one self-built, too-narrow coffin.

But the self-made casket can cost a lot less than a low-end wooden coffin from a funeral home, which on average runs about $2,000.

Lindquist said he had some help from local funeral parlors when designing his product. For instance, he changed his caskets’ bottoms from having a winged-out part to being completely smooth, which makes it easier to load into a hearse. He said he has not had problems like these with his products.

Lindquist said his new company is an experiment that he doesn’t expect to make him rich.

“I just saw an opportunity,” he said.