Furniture Design: 2012

Tuesday 6 November 2012

For the final model I went with a thicker polypropylene, 4.5 mm. I also had to order a larger sheet, 1500 x 1500, to fit the new larger model. I also fixed the plan so the legs were laid out evenly to prevent twisting. To stop the stool from compressing, we decided to add tension wires to the legs to keep them from bending out. The wires would also provide extra height for the stool. Before I cut the final, I made several laser cut prototypes out of cardboard to figure out the placement of the holes on the legs and on the feet.

CNC machine

Final stool fixed with bolts

Before the wires were added

Steel tension wires with crimps

Prototyping

Second Prototype

For this one, I used 1m x 1m of 3 mm thick polypropylene. I kept the "X" Shape, but altered the feet and how all the legs attached. The "X" though caused some twisting and distorting, so that would have to be changed. Once folded, the stool only reached 200 m high. Even though the plastic was stiff, it was still too soft to be able to hold weight without compressing, so there needed to be another support element to stop the sagging.

Originally, rivets were to be used but the legs were too difficult to hold and keep the rivet in place. I realized also that I needed to fold all 4 legs up at once and use bolts.

Prototyping

First Prototype

Made a simple one out of cardboard to see how the arms would bend onto each other and how large the seat would be. The first stool is laid out in an "X" shape.