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Two in One

Two in One

coline Prevost
January 17, 2017
1 Comment

Two in one is base on a simple idea, it is basically two chairs in one. Both of them are built on the same base, only the backrest changes allowing to develop a range of chairs while minimizing the production cost. The chair has been designed around a central piece of steel creating the structure. From there, all the others pieces can be assembled from the feet to the back.



The curves of the chair reminds an industrial style, inspired by icons like the Tolix chair or the Thonet chair with the bending wood. The chair is deliberately rounded to avoid a cold feeling due to the use of metal, and look more friendly. It has definitely something of the Scandinavian design with really pure and minimal shapes I particularly like. I can imagine the chair with really different colors and finishes which could add a more playful style. The metal part as the wood could be painted to increase the possibilities.


The idea of this chair came from sketches and moodboard. I was turning around the Thonet chair when the idea pops up. This project is still conceptual, but I might try to make one. I turned to 3D CAD to visualize the concept. That often helps me to face all the constraints and redesign some of the previous design assumptions as I work my way through the concept. I have done couple of mock-ups to validate the concept, and 3D printed some of the pieces. One of the problems was the fragility of the structure. How to avoid the metal bending under the weight? I had to find a discreet and effective solution. Another detail was to draw the chair in such a way the seat was pleasant in both directions. I wanted to make sure the armrest support was not incommode for the thighs when seated.

While I was working on this project, I was always wondering about the manufacturing process.

The feet and backrests are made of beech and the structure is made of metal. The support of the feet is designed to go down sufficiently in the wood to prevent it from bending. The structure itself is reinforced by two crossed bars at the fasteners.

The steel structure is made by stamping into 4 parts from two different molds, the front mold and the rear mold. Then they are welded together and strengthen with a U-shaped rings allowing a support for the wooden seat to be screwed on. Finally, the feet and backrest are screwed to the steel structure.

The back of the chair despite its thinness keeps a flat part to allow to lean back comfortably.
The seat is wide and slightly curved for a better convenience.






The project has been well received, more than I thought it would actually. I have been contacted by couple of design magazines since I published the project on Behance and I have been selected to feature in the Behance Product design gallery.

For more information about my work: https://colineprevost.squarespace.com/

coline Prevost

I am a french industrial designer. I graduated a master degree at ISD (institut supérieur de design) in 2014 in France, after a bachelor at LA SORBONNE in design theory and a two years degree at ENSAAMA in product design. I spent the last year working at Branch Creative in San Francisco and I am currently working as a Freelance designer in France.

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