May 28th, 2013 by SLSolarz
Thanks for checking out my blog post! As I promised in last week’s entry, this week I will reveal whether or not I solved Frank Lloyd Wright’s design problem. The Origami Chair famously has a tendency to tip forward; especially as the sitter scoots forward in preparation for standing up. Wright’s solution was to add anti-tipping feet; he added metal caps to make the extra pieces look more intentional.
This photo provides a good view of FLW’s anti-tipping feet. They are the pieces of ply with the metal tips.
My thought was to make the front feet larger, providing a greater surface area and, therefore, a lesser proportion of the sitter’s weight on the front corner of the feet. Good idea?? I originally made the feet about 4″ long (a 25% increase from the FLW model) and then sliced off a couple of inches from the bottom of each side of the chair, doubling the length of the feet. Result??
I still had a tipping problem. The seated person wasn’t in any danger but the experience of getting up from the chair could still be a bit startling–not a desirable quality for a chair!
I considered tossing the chair out and moving on to another project until a fellow member of Twin Cities Maker mentioned that a chair with a tipping problem might make a great rocker. Thus began a new design!
So, next I carved a model rocker out of polystyrene foam.
Here the foam rocker is taped to the table to approximate how it would look once attached. The paint chip that I have taped to the side is a color I considered for the chair.
Determining the arc of the rockers turned out to be quite a research project. Eventually, I found a simple formula for finding the length of the radius of the circle from which the arc should be drawn. That is seat height x pi. I brought my model and 2 tubes to a steel-bending expert.
One of my rockers is finishing its final bend. This machine has a limit of 2 in diameter metal.
Next, I made several steel plates to screw to the feet and tail of the chair so that I could connect the chair to the rockers.
Positioning the chair, just right, onto the rockers was challenging. If there is a next time, I will get help holding the chair as I weld it to the rockers.
I propped the chair just as I wanted it to sit on the rockers so that I could design the hardware to connect the front feet. You can see on the left that I used a plate welded to a square rod to connect the tail.
Next week, I will discuss creating the exterior of the chair.