Monochrome Watches
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Watchmaker Jiro Katayama, the Man Behind Otsuka Lotec and Japan’s new Sensation

From the land of the Rising Sun comes a distinctly industrial vibe inspired by instrument gauges and film cameras.

| By Robin Nooy | 6 min read |

Some brands want a global presence, while others are perfectly happy to focus on a much smaller part of the world. Such is the case for Jiro Katayama, a Japanese watchmaker who produces watches under the name of Otsuka Lotec. This low-key but high-impact independent watchmaking atelier has been making the rounds online despite selling its watches exclusively in Japan. Despite this, and fuelled by our never-ending quest to bring you interesting stories from all around the world, we reached out and asked him a couple of questions. Here are the answers, including news that there’s a new model – the No. 5 Kai – on the horizon.

Robin, MONOCHROME Watches: Mr Katayama-san, can you tell us about your background in watchmaking and how you ended up founding Otsuka Lotec?

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Jiro Katayama, Otsuka Lotec – It all started around 2008 when I acquired a small lathe. I started working as a car designer and later made a living as a product designer, but at the same time, I wanted to create with my own ideas. Then, out of curiosity, I bought a lathe and started making watch cases to practice metalworking. I became fascinated with watchmaking by making watch cases and learning about watches. I produced No.1 to No.4 in 2008-2012 and started selling No.5 to the public in 2012.

You are a self-taught independent watchmaker. How did you learn the necessary skills to build watches?

As you said, I am a self-taught watchmaker. I have a background in car and product design. When that desire to create something started to grow, and with the lathe I mentioned, I started looking online for information. I have learned how to machine things mostly through Google and YouTube.

The name Otsuka Lotec and the inspiration for your watches, where do they come from?

My workshop is located in Otsuka, Tokyo, very close to Ikebukuro. I started there by myself in a small way. I like things with an analogue, low-tech feel, which is where the brand name comes from. I get my inspiration for my watches from old film cameras, industrial instruments and gauges.

Your watches are currently only sold in Japan and rarely surface in Europe or anywhere else. What’s the idea of focusing on Japan?

We started with what we could do with our current capacity. We had no choice but to develop the brand only in Japan until the quality of the watches was stable and the production capacity was strong enough to start delivering watches outside of Japan. I don’t know when that will happen since we’re still focused on Japan for the time being.

The majority of the watch community might have been unaware of your work until fairly recently; what has changed for you?

That basically happened through social media, like Instagram. The video by Swiss Watch Gang also helped with that. It’s exciting that there are more people and opportunities to see Otsuka Lotec, but what we do may not change that much. I will continue to create mechanisms that I find interesting. And as long as there are people interested in them, I am happy with the way things are.

The module of the Otsuka Lotex No 6 during assembly.

Currently, you have two watches in your collection, the No 7.5 and the No 6. Can you tell us about both?

No. 6 was introduced in 2015, and the current version was launched earlier this year. It features the retrograde hour and minute hands and the central seconds disk. The design comes from industrial instruments such as pressure gauges. The hands are mounted in the lower part of the movement and follow a fan-shaped display for the hours and minutes.

The No. 7.5 was introduced in 2021, and I updated it slightly in 2023. The design is an evolution of the No. 7, which had two lenses, one for the jumping hours and one for both the minutes and seconds. The No. 7.5 has three independent displays for the jumping hours, minutes and seconds. I got the inspiration from vintage 8mm film cameras.

You use base movements from Miyota but do a lot of work in-house. Can you elaborate on that?

I needed to develop the modules to realize the design I had in mind. I designed and manufactured them all by myself. The number of parts in a module depends on the model, but it consists of about 30 components. Currently, three watchmakers from Precision Watch Tokyo are supporting me in the production.

I understand there’s a new watch on the horizon, the No. 5 Kai. What can you tell us about it?

Yes, that’s correct. It will have a wandering hours indication. It was named “No. 5 Kai” because it inherited the case design and the ball bearings from the previous model, No. 5, which was sold for the first time. The small seconds are put with the wandering hours because the watch is always seen to be moving. I am very much looking forward to this model, and I hope people will like it!

Will this again focus on the Japanese market, or will it become widely available?

In principle, we will initially sell online domestically as we have done, but in the future, we would like to consider selling overseas.

The minute ring of the Otsuka Lotec No. 7.5 is being fitted to the in-house module.

You’re also closely working with Hajime Asaoka, one of the leading Japanese independent watchmakers. How did that come about?

Of course, I have long been familiar with and inspired by Mr. Asaoka’s activities and work (also the mand behind Kurono Tokyo). We first met in 2022 when a staff member of his company personally purchased one of my watches. Until then, I had been making and selling watches by myself, but Mr. Asaoka became interested in the watches I made and decided to support me. I received support in terms of both personnel and equipment. Currently, I make prototypes at my home workshop and direct the production at the Precision Watch Tokyo’s workshop.

What are the plans for Otsuka Lotec moving into the future? What can we expect in the long run?

No.5 Kai will be released at the end of the year, and the all-new No. 8 next year. I am also preparing a watch with an in-house movement under the Jiro Katayama brand, which is exciting!

How can people currently get in touch or perhaps even purchase a watch?

Public sales overseas are also being considered in the future, but for now, we will continue focusing on Japan. People can visit my website and contact me there or send me a message on Instagram.

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1 response

  1. Hi Robin, thanks for sharing.
    Otsuka Lotec is under my radar since some time, I like unusual ways to tell time and this is the proof that unusual doesn’t mean necessarily expensive. I love the analog, steampunk look of the watches, very japanese in the Miyazaki way if you know what I mean.
    Only pity they’re sold in Japan only…Maybe it is worth a trip there !
    Best regards,


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