Boks Stol
(Danish for "box chair")
While studying furniture design in Copenhagen, I designed and built this chair that disassembles into a portable box.
My goal was to create a chair with the qualities of a good friend; it should be honest, approachable, friendly, adaptable, and communicative. For that metaphor to feel appropriate, a person's relationship with the chair couldn't be limited to indifferent sitting. I wanted to design around a more intimate and interesting connection with the object.
One of my favorite pieces of furniture design is the 1997 Paper Tube and Plywood Stool by architect Shigeru Ban. I love how simple it is, and the way the legs are stored so neatly inside the seat is incredibly elegant. This was my main inspiration. I hoped to create a standard, simple side chair with parts that could be easily stored within the seat.
My first priority was ergonomic proportions, measurements, and angles. Though my process was completely analog, I designed this chair parametrically. Once I established the angle of the back and the seat's depth and height from the floor, I designed the parts around those measurements. Every number trickled down from the initial constraints. The Scandinavian philosophy of functionalism helped me to justify that every measurement was what it was for a reason. 
The final chair contains no metal. 
It utilizes only maple, birch, glue, and leather.

Normally in my design work, sketching is a hefty part of my process. However, when I decided to create a chair with moving parts and interdependent measurements, I knew that compressing the ideation into two dimensions would result in problems down the road. So my first sketch was the model above. With this kind of puzzle, I would normally work in Solidworks, but I decided to experiment with my process and leave my computer behind. So, every measurement and alignment was conceived the old-fashioned way. I believe this lead to my design becoming a simple and concise demonstration of the idea.
I worked with 1:1 plan drawings and 1:5 scale models.
An updated model made of paper board and pine for better stability and precision. In this model, I had the back stretchers protrude from the seat in box form, allowing a crossbar to slide through and lock the box closed. It also seemed to suggest itself as a handle.
At this point, I was thinking a lot about whether my chair would be properly comfortable. I didn't want to make a chair that was fun to assemble but not to sit in. 
This first manifested in my process with an ad-hoc modification of my 1:1 drawing, where I modified the angle of the seat from the floor. Just looking at the drawing, I could see that the design had lost a lot of its simplicity. I was muddying the concept.
I then began to consider integrating saddle strap weaving to provide comfort. After that seemed unnecessarily complicated, I was inspired by a Bernt Pedersen chair design that used slats cut into plywood to afford flexibility. I started to sketch more to figure these ideas out.
I ended up deciding that the idea of cutting slats into the seat was the most elegant way I could integrate comfort. It utilized the form language I was already using - rectangular cuts out of rectangular forms.
In the workshop, I prototyped the slats by clamping cut plywood in a row and sitting. I was satisfied by the give and stability provided by the arrangement of slats, but I tabled the experiment as an element to develop more in the future. I'd like to give such a dynamic element the time and experimentation it deserves, so with the beginning of construction approaching I decided to construct the first prototype without slats and assess how the base ergonomics of the chair performed.
When my chair finally came together for the first time, it was on the very last day we had access to the woodshop, after we'd cleaned up and shut down the machines. The place was spotless by the time the chair's back finally dried, so everyone stood around and set their attention on me as I was finally going to see if my chair would be a chair. A circle formed around me as I assembled it, and when I sat down for the first time, it held me up.
People actually cheered!
It was a very surreal and happy moment.
After that, I spent almost a full day applying a traditional danish soap finish in three coats, alternating with fine sanding to achieve a smooth, soft surface.
Last of all, I hand-sewed a leather strap that fit through a hole in the protruding ends of the back stretchers, looping around and through the protruding crossbars, locking the box shut and providing comfortable portability. I burnished the edges of all leather parts with beeswax to finish them off.
My chair was displayed at a final exhibition with DIS in Copenhagen, and then I converted it into a box and checked it on the plane back home. My cat was very grateful, because it has become his new fort to hide under.
In Copenhagen, I walked for over an hour with the Boks Stol at my side and finally settled by a lake with my friends to have a celebratory beer and say goodbye. It was a wonderful punctuation mark on my summer.

I am still developing the Boks Stol. Now that I've cemented and demonstrated the concept, I am certain that modern technologies like Solidworks and a CNC router will perfectly compliment the logic that I have built into the design. I hope to make the chair lighter and experiment with other locking/carrying methods. I am also still experimenting with the integration of slats to provide comfort.
Stay tuned.
Lounge Box

Back in Pittsburgh, I set out to improve the chair. As planned above, I aimed to design a more comfortable chair, utilizing the flexibility of plywood for slats in the seat and back. I decided to make an armchair, to fully embrace the goal of comfort. Of course, it would still have to collapse into a box.
My final product, as seen to the left, was born largely through time-intensive handwork. Though I designed the chair in Solidworks and cut the plywood pieces with a CNC router, I spent weeks chiseling diagonal holes into the plywood at precise angles. Once all of the holes were finally done, cutting and fitting the interfacing rectilinear parts went smoothly.
Here I tried cutting, then flexing plywood slats with different grain directions. Plywood is made of sheets of veneer, stacked in alternating perpendicular orientations to provide strength on both axes. In considering how to make flexible slats, Josiah (the School of Design shop manager) suggested that I try cutting the slats "on the bias," or at 45 degrees.
In the same way that fabric behaves in this orientation, the diagonal-grain plywood was far more flexible.
Then, to determine the dimensions and quantity of slats, I worked backwards. I knew I wanted the slats to flex around 1.5 to 2 inches, as they would then stop at the bottom surface of the box seat.
I attached a mechanical hanging scale to the slat and pulled until it flexed to the degree I was hoping. Using the recorded weight required to achieve that degree of flex, I calculated the required number of slats to support a good range of sitting-human weights.
It was then time to design the chair, which I did parametrically in Solidworks, so I could constrain every dimension to defined ergonomic proportions and flat-pack requirements.
Before I could begin working the chair, I had to create models of the two most complicated sections of the chair design. The first was of the joint between the front of the box, the vertical leg, and the diagonal crossbar/back leg. In doing the first, I learned some of the subtle necessities of chisel work. The second was the sliding dovetail joint between the top of the front legs and the underside of the arms. Creating the model helped me to determine the required router setup and tolerances for those cuts.
I spent weeks with these two jigs. I used both as references for sanding, then chiseling slanted holes into the plywood box faces at precise angles. It was slow, careful work.

Finally sitting on the glued box seat! Nothing broke :-)

I then cut and sanded the rectilinear parts down to size. I had to ensure that the thicknesses were fit correctly to the holes in the box, with a tolerance that provided the right amount of friction and mobility. All of the parts with diagonal holes started halved. I cut the holes with the table saw, then glued the halves together.
This final, big step was a bit of a 'moment of truth,' because the tolerance had to be just right to grip and slide. If I made an error and removed too much material, the entire leg would have to be redone. So, I made many passes with the router, on both sides, easing up to the perfect cut depth by using layers of tape as shims, bringing the router slightly forward each pass, then checking the fit of the joint. The photo to the right of the gif shows the original model I made of the joint. If you look closely, you'll notice a slightly angled gap above the dovetail. That was due to a few subtle errors, and taught me how to be more precise with the final parts (like the one shown in the gif on the left).
Here it is, finally assembled in chair form. Much work was still to be done in fine-tuning tolerances, and in adding some finishing details like the angled cut at the bottom of the front legs and the rounded nose of the arms. That was out of my mind at the moment, pictured below, though. I was focused entirely on how comfortable it was! The slats in the seat bent in a surprisingly comfortable way, and the backrest flexed just enough to cup my back. It was very pleasant!
On the right, you can see the Boks Stol and Lounge Box together on Flagstaff Hill, in Pittsburgh PA.
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