The exterior of the chapel consists of 18.5m long twisted stainless steel panels
Consistent Silky Blast finish is applied
The conical shape is achieved by folding a two-dimensional fan-shaped surface
■World Class Sized Extra-long Stainless Steel Panels
Kikukawa participated in the metal construction of the symbolic Chapel of the MIHO Institute of Aesthetics situated in the mountains of Shigaraki.
This was the last significant work by the world-renowned architect, I.M.Pei; a conical shape covered in stainless steel panels that are roughly 18.5m long. The innovative and functional design results from folding a two-dimensional fan-shaped surface into a cone (lemniscate curve), with the rear panels being slightly taller. These stainless steel panels are individually twisted to emphasize the beautiful curvature.
■Curved Outsized Panels
The exterior panels are crafted from 5.0mm thick 18.5m long stainless steel that amounts to roughly 100 tons in weight. The panels are trapezoidal in shape, their width ranging from 600 to 1500mm, and every 51 stainless steel panels are individually custom-warped.
To implement the shape, 3D-CADs were used to understand, design, and calculate the panels’ backing frames of the individually shaped cladding.
To optimize and craft the outsized individualized panels, Kikukawa developed a specialized pressing methodology and bespoke jigs and adjusted the cutting equipment and machinery to improve the production line. Difficulty in production, such as cutting out curved edges from the curved large panels, were overcome with our expertise. Such continuous creative efforts led to the precise implementation of the design.
■Developing a bespoke Silky Blast Finish
The exterior stainless steel panels are finished with Kikukawa’s proprietary bead blasting finish, Silky Blast. A bespoke Silky Blast finish was developed for this project, 2-Z+R10, which has a calmer gloss level than the typical Silky Blast. By doing so, Kikukawa was able to achieve a consistent finish regardless of the reduced quality level of the stainless steel material due to its outsized width, length, and thickness (over 4mm). In addition to the bespoke Silky Blast finish, an artificial coat of passivation coat was applied to enhance the natural corrosive-resistant protective coating.
To bead blast and apply the passivation coating on the outsized panels, Kikukawa installed blasting machinery and set up designated production lines and jigs.
■Transporting and Installing the Outsized Panels
The 18.5m long panels were transported using special trains used to transport bullet trains, with road permits. The panels were placed on top of jigs specifically made to accommodate the transportation of outsized panels, and carried from Chiba to Shiga (roughly over 500km) over 2 nights.
Due to the extreme size, individualized twisted shape of the panels, and the structural design of panels being connected at a single upper front point, the precise installation was a challenge. Kikukawa addressed these difficulties from the detailed design stage with our expertise, and in close collaboration with the general contractor, conducted and reviewed prior discussions of detailed lifting plans, and made full use of our craftsmanship in the actual installation. By doing so, the continuous curved surface was realized as visualized by the designers.
■Receiving the JSSA (Japan Stainless Steel Association) Award for Excellence
The project was highly evaluated by the clients who quoted, “the technology to apply bespoke twisting to panels exceeding 18m could only exist in Japan.” Especially in shaping and finishing the metal, Kikukawa’s proprietary technology was essential.
This extraordinary project and its stainless steel façade received the 15th JSSA (Japan Stainless Steel Association) Award for Excellence in 2013. The architecture was highly evaluated for the various challenges that were addressed and overcome from the procurement, crafting, to the finishes, and the Silky Blast finish that elicits the beauty of the stainless steel material.
‘MIHO Chapel’ also received the 54th BCS award organized by the Building Contractors Society in 2013, for excellence in design, building techniques, and mutual understanding and collaboration between the client, designer, and the contractors.
|Extra-long Exterior Panels||Stainless Steel||Twisting
Silky Blast (Bead Blasting)
MIHO Institute of Aesthetics
|Architect||Project Architect: I.M. Pei Architect|
Associate Architect: I.O. Architects
Executing Architect: Masatoyo Ogasawara Architects
|Location||Koga City, Shiga|