We make a pendant light named bisque at a metal-forming factory in the Edogawa ward in Tokyo using a technique called metal spinning. Metal spinning is a manual metal-processing technique in which a craftworker forms a hollow bowl shape from a single, solid, flat metal sheet that is pressed tightly against a mold using a forming bar while the sheet is rotated. This technique is used in a wide variety of areas such as in the aerospace industry for the nose cone of rockets as well as parabolic antennas. Although this manual technique is not suited to mass production, even complicated shapes can be formed by hand by skilled artisans.
Bisque in English can mean unglazed china. To give the metal-spun aluminum main body a texture resembling white unglazed china, we spray paint the thin and lightweight aluminum surface. We achieve weight savings by manufacturing it from a [single] thin aluminum sheet which is only 1.2 to 1.5 mm thick. This makes even the largest size light enough to hang with a standard household ceiling bracket. When we make a product, we do not usually start by devising a specific shape or design. Mostly, product development is inspired by an encounter with a specific product manufacturing process.
We got the idea for this particular light after seeing the metal-spinning technique in use and seeing other products made at existing factories. When we visited the metal-spinning factory for the first time, after being introduced to the process by a friend of mine, we saw a variety of products manufactured using many different molds. What especially caught our attention were the large bronze and aluminum main bodies of percussive musical instruments called timpani — as used by classical music orchestras. When creating a deep bowl using a large bronze sheet, you not only need to employ the principle of leverage but also ensure technical accuracy and apply optimum body balance to the tip of the forming bar. At first, we made two types of pendants, in both bronze and aluminum, by using a timpani mold without any modification.
However, after making them the same shape as the timpani and displaying them for trial purposes, we still felt something was missing. Making a metal mold for a new product from scratch would have cost a few million yen per mold initially. Come to think of it, product development these days often pays less attention to the inherent nature of things and how they are made, giving higher priority to formal efficiency and good design in order to achieve a successful business outcome based on the balance between the initial cost and sales generated. In this age of efficiency and “profits-coming-first”, superficial novelty and concept are valued more for designs and products employed for our daily use.
Going down the profits-come-first route, we might have inadvertently lost sight of the true nature of things and human life. Our target was to make 80% of the main body from an existing timpani mold and the remaining 20% from our own mold in order to create a new product that combined both shapes. The thematic challenge was how to create one complete product from two separate molds by combining them in an integrated manner. Eventually, we prepared five sizes of bisques and decided to make use of a timpani mold for our largest bisque and to use our own molds for the other sizes.