Chair Protoype

I designed and fabricated a chair prototype for a third-year furniture project.

Brief

Design a comfortable wooden chair. Explore the notion of comfort and how a hard material such as wood can provide it.

Criteria

Intent

Two of my favorite armchairs are: the classic Round Chair, designed by Hans Wegner in 1949; and the contemporary Hiroshima Armchair, designed by Naoto Fukasawa in 2008. They're both elegant, purposeful, and quiet.

Inspired by these two chairs, my goal was to make a low-back armchair for dining or conferencing; combining a tactile, vintage-looking woven seat, with contemporary forms.

Dimensions

Materials

Ideation sketches.
Digital sketch model in Autodesk Fusion.
1:4 scale sketch model.
Digital presentation model.
1:4 scale presentation model.
Full-scale ergonomic mock-up.
Revised digital model.
Revised ergonomics.
Full-scale aesthetic mock-up.
Laminated wood to form blocks for backrest and armrests.
Wood prepared to be laminated for front and back rails. 
Curves drawn on paper, and then glued onto blocks.
Front and back rails roughly cut out on bandsaw.
Outer curves shaped on disk sander.
Inner curves shaped on spindle sander.
Made a jig for routing slots into rails.
Routed slots into side rails.
Layed out curves for front and back rails, using a drawing bow.
Roughly cut off curves on bandsaw.
Outer curves shaped on disk sander.
Inner curves shaped on spindle sander.
Slots routed into front and back rails.
Side rails cut to final length.
Front and back rails cut and shaped to final length.
Miters on backrest and armrests roughly cut on bandsaw.
Miters shaped to final angle on disk sander.
Backrest and armrest blocks made in Fusion, printed in full-scale.
Backrest and armrests printed in full-scale.
Blocks fitted on printouts taped to 3/4" particle board for flatness. 
Layed out mortise locations on backrest and armrests.
Stacked various plywoods to set height for Festool mortiser.
Successfully mortised parts for floating tenons.
Used light table to trace blocks onto final shape printout.
Carefully glued printout onto underside of backrest and armrests.
Cut printout and separated assembly.
Drilled mortises into armrests at rake angles.
Turned, sanded to 180, and polished legs on lathe.
Made jig for routing mortises into legs.
Calculated mortise locations, layed out in Illustrator, and printed.
Taped printouts to legs.
Aligned mortise locations to jig.
Successfully mortised legs.
Setup for mortising front and back rails.
Successfully mortised all rails.
Slightly rounded over slots, using sandpaper and file.
Roughly rounded over front and back rails with rasp.
Rounded over side rails with table router.
Made jig for rounding out ends of rails on spindle sander.
Sanded all rails to 180 grit.
Legs cut to final length and angle.
Roughly cut armrests and backrest on bandsaw.
Tested fit of legs.
Scribed tenon shoulders to proper angle.
Angled shoulders cut with handsaw and chisel.
Side rails glued to legs.
Leg assembly glued together.
Backrest roughly shaped on machine sanders.
Armrests roughly cut to thickness on bandsaw.
Backrest and armrests glued together.
Back-arm rest shaped on machine sanders.
Underside of back-arm rest shaped on table router.
Armrests roughly sculpted with die grinder.
Finer sculpting done with rasps.
Sanded to 180-grit with orbital sander and hand sanding.
Glued top assembly to bottom assembly.
Applied Osmo Clear finish.
Realized traditional methods of weaving would not work for this.
Tried unorthodox symmetrical weave. Better but not acceptable.
Revised symmetrical weave.
Not perfect, but the best I could do for this chair.
Underside of seat.
Not bad for my first time weaving anything.

I wanted to use Osmo Raw, but it wasn't available at the moment. Osmo Raw would have slightly whitened the wood, creating a subtle contrast to the Danish cord.

Only when I started to weave, and watched YouTube tutorials, did I realize that this chair design was not suitable for a rush patterned weave. I had considered doing a basket weave pattern. But according to YouTube videos, I needed L-shaped tacks which I did not have and could not find to purchase. Also, the slots in my rails seemed to make basket weaving very difficult. Wegner's Round Chair has slots in the rails, but each strand was only the length of the width or depth of the seat (not one continuous strand), and each strand was stapled into rabbets on the underside of the rails.  I did not have staples, and my rails did not have rabbets. I had considered wrapping around the entire rail, covering the slots. But I had worked hard to make those slots, and I wanted to show them off. After a couple days of trial and error, I eventually came up with my own method of weaving a rush pattern into slotted rails. It's not ideal, but it's comfortable, and it doesn't look too bad.

The armrests should be parallel to the floor. But for some reason, the back legs are a little too short. Also, I accidentally made the backrest a little too thin. 

Overall, I'm quite happy with the chair. This is also my first time sculpting a seamless curve from one part to another, and I'm pretty happy with how that turned out. Early on in the project, I was worried that I would just be copying the Round Chair and Hiroshima Armchair. But after getting feedback on my ergonomic mock-up, I was glad I was able to come up with an armrest shape that would subtly differentiate my design from Wegner's and Fukasawa's. I think the shape of the armrests are congruous with the shape of the backrest, while creating an interesting transition between the two, while maintaining a continuous curve from elbow to elbow. The rush pattern also speaks well to the diagonal back-arm joints.