Mount Airy seventh-grader runs his own knife-sharpening business

Wearing safety goggles with a brown “Lost Arts” apron tied around himself, 12-year-old Mozi Weisenberg demonstrates the sharpness of a six-inch knife he made in his family’s Mount Airy basement.

He holds a piece of paper at the top with his left hand, then quickly draws the gleaming silver blade through the sheet straight down. The paper barely flutters as the knife slices through with ease, half the cut sheet floating to the floor.

“That’s incredibly sharp,” says Mozi, a home-schooled, Frisbee-flinging history buff who last year started Mozi Sharpening and Tool Restoration, sharpening knives for $5 apiece.

“He’s a character,” says his mother, Molly Weingrod, 41, a psychotherapist and childbirth educator who provides information to expectant parents. “He’s an autodidact who built his own kayak at 10.

“This child has gone through almost all of the Montgomery County library system. It’s challenging for me to teach him.”

Soft-spoken and engaging, Mozi, the second oldest of four children, is not as impressed with himself as everyone else is.

“I don’t love sharpening; it’s just necessary for money to buy tools for woodworking,” he says, sounding more like a seasoned pro 20 years into a career than a gifted tween indulging his curiosities.

Mozi got into woodworking through his father, Joey Weisenberg, 41, a musician, composer, and Jewish music educator. Some of Weisenberg’s wooden sculptures — several of animals and people’s faces — adorn the family’s lawn.

Now he works as Mozi’s assistant. “I’ve been telling him what to do,” Mozi says, smiling, living every kid’s dream.

Mozi prefers old tools for his own projects, many from the early 20th century. ”Most new tools don’t work very well,” he says.

Not long ago, he purchased a $90 hand plane on eBay that was made around 1918, to pair with another costing $180 from the same era.

Last year, he created online fliers to announce his business. Mozi now has around 20 customers, one of whom is chef and pickle maker Mordechai Schram, a family friend who lives in the area.

“At first I figured I’d help him out, you know, the ‘That’s so cute, he’s an enterprising kid’ sort of thing,” says Schram, whose kitchen is called hamutzim,which means pickles in Hebrew.

“But Mozi has such skill. He’s an artisan, the best knife-sharpener I’ve ever used. I go to him every three months. My knives now are impeccable, spectacular, maintaining their sharpness longer than they ever did before.

“He’s serious, he knows so much about knives, and he provides great value. I recommend him to other chefs. And he’s a wonderful young man with great life energy.”

Mozi says he learned his craft mostly from reading about sharpening, then just doing it. “Many people don’t know how to work with their hands anymore,” he says. “There’s a self-reliance people have been losing over the past 100 years.”

Mozi explains his process, how he uses a belt sander, then a whetstone, which looks like a blackboard eraser made of man-made diamonds electroplated to a metal plate.

The goal is a honed blade edge coming to a perfect point, “nothing flat or dull,” Mozi says, holding up a gleaming knife that might frighten most parents.

“In the beginning,” Weingrod said, “when he was 7 or 8, I had qualms about him handling tools and knives. But he’s really careful. He began cutting his own food when he was 4.

“We never started him on toy tools. Our philosophy is ‘Real stuff or nothing.’”

Aside from the 8-foot-by-22-inch kayak (which proved its worth on the Lake Galena reservoir in Peace Valley Park, Doylestown), Mozi made a desk for Weingrod and created his own workbenches, among other projects.

When Mozi isn’t working in the basement, he’s playing Ultimate Frisbee. Asked what shows he likes to watch on TV during downtime, Mozi answers, “We don’t have a television.”

Often, he reads history books, many about World War II. “I like equipment and machines, and the war-shaped human history and many innovations that were first used for war,” Mozi says. “I’m not into fiction.”

Ask him what he’d like to be, and the answer isn’t what you’d normally hear.

“I’m not interested in making a lot of money,” Mozi says. “I’m really into self-reliance, and I’ll be trying to live off the grid, with less reliance on energy because of climate change. I want to do creative things.

“Humans mow everything down and change the landscape. There’s no nature in it at all.”

Lovingly awed by her son, Weingrod admits, “At this point, if there’s something not working in the house, we ask, ‘Moz, can you fix this?’ Or, ‘Do you know anything about this particular time in history?’

“His mind is very active and hungry. It’s an amazing thing to watch.”