WATCH & JEWELRY /
FEATURES
July 3, 2026
Feature: The Inheritors of Time | We want to offer true watch repair. Even if it means being left behind by the times.
Feature: The Inheritors of Time | Tsutomu Sato (Zenmai Works Inc.)
A watch is a tool for marking time. Yet, time continues to flow even after the hands have stopped. Inside the case lies the "mechanism of time," a combination of dozens of precision parts. A mainspring winds, gears mesh, and the balance wheel oscillates. An immense accumulation of precision and skill is dedicated to the simple act of a mechanical watch ticking away a single second. Tsutomu Sato, president of Zenmai Works, whose workshop is in Yaesu, Tokyo, operates under the motto, "We want to offer true watch repair. Even if it means being left behind by the times."
Photographs by Kaku Ohtaki | Text by Takashi Tsuchida
I Didn't Want to Work on Watches
“I don’t have anything particularly interesting to say…” Sato began with a small laugh. He didn’t choose this path because he loved watches. In fact, he says, his feeling was closer to, “I absolutely didn’t want to work on watches.”
After graduating from industrial high school, he first joined a car tuning shop. However, he was assigned to parts manufacturing instead of the repair work he had hoped for. In a moment of youthful impulsiveness, he quit. He then moved to a company that manufactured motorcycle parts, but something fundamental felt unfulfilled.
The turning point came at age 20. An acquaintance of his father’s approached him, saying, “If you’re just hanging around, why don’t you come work for me?” He visited the company on a whim, thinking, “I’ll just take a look.” It was Isshin Tokei—a watch import company renowned as the distributor for Patek Philippe and Chopard. That became his entry into this world.
At the time, there were no vocational schools training watchmakers. Sato’s generation had no choice but to join a related company and start from scratch. It began with the absolute basics of manual work: how to hold tweezers, how to sharpen tools, how to make parts.
“It was interesting,” Sato recalls. The skills he had acquired in industrial high school for parts manufacturing unexpectedly proved useful. He realized he could create things from a perspective his seniors didn’t have, and that’s when the desire to continue in this profession began to sprout.
The Weight of "Thank You"
The service center at Isshin Tokei was on a single floor, with only a thin partition separating the watchmakers' workspace from the customer reception counter. From beyond that partition, he could hear customers' voices. He heard expressions of gratitude, and he heard complaints. But the former were overwhelmingly more frequent.
“Even though we were being paid, people were so grateful. I thought, what a wonderful job that is.”
This was around the time he was 21 or 22. Those voices became the origin that anchored Sato to this profession.
Today, most customers who visit Zenmai Works are people who have arrived at this place after a long journey. They come here after being turned away by manufacturers, after trying various other places. “Many people bring their watches saying, ‘We understand there might be some drawbacks, but we still want it repaired,’” Sato says.
“Our customers understand well when they come to us. These watches are incredibly important to them, so I’m truly grateful when they entrust them to us.”
To be the last resort for those who have cherished their watches with affection—maintaining that role is at the core of this workshop’s existence.
What Constitutes "True Repair"?
A search for "watch repair" in Tokyo alone yields hundreds of service locations. However, for many vintage watches, the answer customers receive upon bringing them in is, “We don’t handle that,” or “We can’t, because there are no parts.”
“True watch repair means fixing a watch even if it requires making parts, performing work that borders on restoration,” Sato explains. “We want to do repairs that go beyond simple overhauls. Such places are becoming increasingly rare, but we will do everything we can for the watches of people who still want them fixed. That’s what we aim to do.”
When asked, “Which requires a higher level of skill, overhauling or repairing?” most people would likely answer overhauling. But for Sato, the order is reversed. An overhaul is merely one step in the process of repair. He wants to avoid being categorized alongside shops that offer only that, and places that perform true repairs. There lies an unwavering sense of pride.
The problem also lies within the industry's structure itself. At manufacturer service centers, a set amount of time is allocated for each repair case. To handle a high volume, it’s faster to replace a damaged part with a new one than to meticulously repair it. Consequently, parts replacement becomes the primary focus of repair.
Looking at the current watch industry, Sato sometimes feels it’s becoming like digital products. The approach is akin to replacing a broken circuit board with an entirely new one. This trend is accelerated by the widespread adoption of silicon hairsprings. After the Swatch Group acquired manufacturers of hairsprings, parts supply became unstable. Silicon parts, which emerged as an alternative, offer certain levels of precision and durability. However, they seem to be steadily reducing the room for craftsmanship. Sato’s words, “I wish they wouldn’t use silicon parts. Before long, repairs might become a complete movement replacement,” carry not so much a sense of crisis as a quiet melancholy.
Returning an existing object, cherished by its owner, with its parts replaced by new ones—can that truly be called “repair”? The manufacturers seem unwilling to directly answer this question.
Read Before Opening
Sato’s “reading” of a watch begins the moment he picks it up.
First, he observes the angle of the hands and the position of the dial. How precisely are the hands attached? He says this reveals the quality of work by the previous watchmaker. If the dial is slightly tilted, he can tell if the customer bumped or dropped the watch somewhere. He might ask at the reception, “The dial is shifted towards this side; did you bump it on something?” Often, customers don’t remember and reply, “Was it?”
Once the case is opened, he sees traces of the previous watchmaker. “It’s mostly negative things,” Sato says with a wry smile, but he notes discoveries like: tools were applied carelessly, screws aren’t tightened properly, why wasn’t this fixed, why was this done… “These discoveries happen every day.” Occasionally, he finds a screw that is “properly tightened,” but that is rare.
“If a watch has been around for 20 years since manufacturing, and several watchmakers have worked on it, even if it was handled properly by one competent person after another, if just one careless person enters the chain, it becomes a mess. It might sound like a frightening story for consumers, but that’s the reality.”
Watches hold memories. The traces etched within them are always revealed to the next watchmaker who opens it.
What Are You Connecting?
When asked about the theme of this feature, “The Inheritors of Time,” Sato paused for a moment.
“I don’t have such lofty ideas… What am I leaving behind? Perhaps my own shame?”
What does he mean by “my own shame”? If he doesn’t finish the work meticulously, his lack of skill will be apparent to the next watchmaker. Therefore, he says, “I work with a pride that might seem unnecessary.” That, he believes, is the essence of this profession. What is etched into the watch is not just skill, but the trace of integrity and pride.
He mentions that some customers occasionally say, “I am merely holding onto this watch in this era.”
“I think, ‘Wow, this person really gets it,’” Sato says, straightening his posture. If he doesn’t properly maintain the watch while it’s in his care, it won’t be in good condition when it passes to the next person. He acknowledges that there are indeed people who approach watches with that kind of awareness. The existence of such individuals deepens the significance of his work.
Philippe Dufour, a renowned independent watchmaker, is said to openly share his unique techniques without reservation—from how he polishes parts to how he crafts tools. Dufour’s words, “If I don’t pass this on, it won’t reach the next generation,” resonate deeply with Sato. While he can teach the methods, whether someone can actually do it, or chooses to do it, is up to the individual. Furthermore, while techniques can be passed down, sensibility and attitude cannot. Sato’s remark, “That’s the most difficult part,” lingers in the mind.
Sato believes the future of the industry will split into two. More shops will likely move towards attracting orders online and handling them with mass-production methods. On the other hand, those who continue true watch repair with the pride of old will drastically decrease in number.
“It all comes down to the fact that nobody wants to do the troublesome work. The more diligently you work, the more you lose money.”
Nevertheless, Sato has no intention of quitting this job. “We will do everything we can for the watches of people who want them fixed”—this singular purpose is the true reason for Zenmai Works’ existence.
Engraving Pride in the Shadows
It is a job that rarely brings recognition but is filled with a certain masculine spirit. Sato laughed, “Well, I suppose there are many other such jobs out there.”
Watchmakers generally prefer not to be in the spotlight, and repair technicians even less so. Furthermore, their names do not appear on the exterior of the case. The work they do remains unseen until the next watchmaker opens it.
Yet, top watchmakers always give their all to the mechanism before them. They maintain their tools daily, precisely tighten even the most inconspicuous screw, and meticulously complete their work down to the smallest details that no one else notices. Why? Not because it will be discovered by the next watchmaker, but because they cannot bear to do otherwise. As Sato puts it, “I work with a pride that might seem unnecessary.” Behind those words lies the nobility of a craftsman.
Both Franck Muller and François-Paul Journe began their careers in restoration. Sato has absorbed the diverse philosophies of past watchmakers into his own work, applying them to his current craft. Perhaps one day he will create his own watches. But there is also the path of continuously breathing life into watches by opening them all, deciphering the thoughts of others. Both are respectable endeavors.
Within a watch, not only time but also someone’s integrity is etched. That work quietly endures until the next watchmaker opens it.
Tsutomu Sato
President and CEO of Zenmai Works. His workshop is located in Yaesu, Chuo-ku, Tokyo. His style—piercings and a T-shirt—shatters the stereotypical image of a watchmaker. The yellow tinted glasses are not so much for eye protection as for his principle of simply wearing what he likes. He loves Vespas and uses one for his daily commute. Although he apparently doesn’t usually wear a lab coat, a custom-made one, resembling a zippered rider’s jacket, was prepared for him on this day.