VDG-Nachrichten 03/2024
Duran glass basins from Japan
in all shapes and sizes
A report by Tsuyoshi Nakamura
Owner of the company NAKAMURA RIKA Inc. in Tokyo, as well as
Chairman and Managing Director of the Tokyo Scientific Glassblowers Union (NRGK)
Tsuyoshi Nakamura is a third-generation glass apparatus maker
who began his professional training at SINWA GLASS WORKS in 1981, which unfortunately no longer exists today. His grandfather already worked as a glass apparatus maker in a company that processed quartz glass, and his father was also employed as a glass apparatus maker. In 1983, he joined NAKAMURA WORKS Co-Ltd. as a skilled worker. Unfortunately, this company is also no longer in existence. In February 1986, he and his father opened the joint company NAKAMURA RIKA Inc. in Tokyo.
He had been a director of the Tokyo Scientific Glassblowers Union (NRGK) since 2006 and became its executive director in 2012. Tsuyoshi gave a technical demonstration at the 2012 ASGS Annual Symposium and received the award for the most significant contribution by an international delegate at the ISGE 2012 in Corning, NY.
However, he is not only present in the USA, he has also attended several VDG conferences, as well as meetings of the BSSG. His work is unique. The editors asked Tsuyoshi to introduce himself and his work on the following pages.
From the start of self-employment to specialization
It all began with orders for the reproduction and new production of glass apparatus in the fields of chemistry and physics. Due to high demand, we specialized in the processing of borosilicate glass plates a few years later. This field of work is still underrepresented in Japan today.
When our company was founded, the necessary knowledge was still in its infancy, but gradually the range of processing techniques expanded and it became possible to produce particularly large glass containers, including fusions onto and into the containers. We have specialized in processing borosilicate flat glass. Our pipe systems and semi-finished products, such as ground joints and taps, are manufactured by other companies. We can then fuse these into or onto the tanks. However, such constructions are rare. In very rare cases, we have to manufacture pipe systems that need to be melted into a tank ourselves, for this purpose, we have a lathe in our own workshop. Unfortunately, repair work on basins is almost impossible.
When we were founded, we had three employees. Currently, we have four, including myself. Since there are only very few companies that can fuse borosilicate glass plates in various shapes and sizes, our customer base is spread all across Japan. This is the reason why we are not thinking of expanding abroad at the moment. We also have a shortage of skilled workers.
The intended use of the Duran glass basins:
Our products were originally used in semiconductor cleaning tanks, but now they seem to be used mainly as experimental equipment for environmental protection.
Brief description of the production process of a borosilicate glass basin
The manufacturing process begins with cutting the glass plates to the correct size and then fusing them one by one with a hand torch. Borosilicate glass plates react very sensitively to tension during and after processing and break quickly if the two plates are not immediately returned to the tempering furnace after processing. A basin develops piece by piece. It must be removed from the tempering furnace hot, processed hot and then returned to the hot tempering furnace while it is still at heat itself.
A very unpleasant activity! If this process could be carried out mechanically, it would significantly reduce the difficulties involved in processing. However, it's all purely manual labour, even with large and heavy objects that have to be transported to the tempering furnace with great care. I normally produce a basin by myself. Only with very large workpieces do I need an assistant to maintain the temperature of a large area with a hand torch. This dissipates small, dangerous tension fields onto larger surfaces, thereby robbing them of their destructive force. The cooling oven then removes the tension from the entire piece.
Tools, holders and supports for the borosilicate glass plates are made in-house from carbon fibre. The thickness of the plates ranges from 1mm to 10mm.
Demanding work that requires passion and flexible working hours
Normal working hours are Monday to Friday from 8 a.m. to 6 p.m., but if the order numbers are too high, it means overtime for everyone, as well as busy Saturdays and Sundays.
But work-life balance is important
My hobbies include a lot of physical activity, such as surfing, squash, fitness training and golf. I think that keeps me healthy.
Commitment to the next generation Tokyo Scientific Glassblowers Union
Even though our company does not offer vocational training, the glassblowing association we belong to is very actively involved in further and advanced training. Among other things, I present my techniques there, which I have gradually improved over the course of 40 years. I also hold seminars, lectures and workshops, as it is my great wish to be able to carry this technology into the future. Even though it is often difficult to pass on the knowledge, I teach it patiently, because there are very few glassblowers in Japan who work with borosilicate glass plates.
Young talent is very hard to come by
Unfortunately, it is very difficult to attract new people who want to be trained from scratch. The knowledge will probably have to be passed on more and more to existing companies and skilled workers in order to meet demand in this way at least.
Attachment
In our issue 01/2020 we also reported on the production of Duran glass basins. Helmut Kammerlander from the glassblowing factory of the Max Planck Institute for Solid State Research and Intelligent Systems in Stuttgart shared his knowledge on this topic with us
Julia Schweifel helped translate this article.
VDG-Nachrichten
Herausgeber
Verband Deutscher Glasbläser e.V., Karlstr. 7, D-48268 Greven
Erscheinungsweise
vierteljährlich im März, Juni, September und Dezember (Sonderausgabe nach Bedarf)
Format
210 x 297 mm (DIN A 4)
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Druck
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Kontakt, Anfragen und Anzeigenschaltung:
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Karin Rein und Thomas Nieß
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